Abstract: Industrial Robots (IRs) are increasingly adopted for material subtraction or deposition functions owing to their advantages over machine tools, like cost-effectiveness and versatility. Unfortunately, the development of efficient robot manufacturing processes still faces unsolved issues related to the IRs poor positioning accuracy and to the tool path generation process. Novel engineering methods and tools are needed for CAD based programming of accurate paths and continuous robot motions to obtain the required manufacturing quality and tolerances. Within this context, to achieve smoothness along the tool path formed by linear G-code segments, the IR controllers’ approximation strategies, summarily reported in the manufacturer’s manuals, must be considered. The aim of this paper is to present the preliminary work carried out to identify the approximation algorithms of a Kuka IR when executing linear moves. An experimental study is conducted by varying the controller settings and the maximum translational velocity. The robot behavior has been acquired thanks to the controller tracing function and then processed to yield relations readily employable for the interpretation of G-Code commands and the subsequent generation of proper robot motion instructions. The obtained formulas allow to accurately predict the robot geometric path and kinematics within the corner transition between two linear segments.
Abstract: The paper presents a preliminary design activity and virtual prototyping of an innovative boat equipped with hydrofoils and hybrid propulsion, with the aim of extending the foil technology from the field of competition boats to recreational day-cruiser yachts and creating a craft with minimal environmental impact. Hydrofoils allow boats to rise from the water, greatly reducing resistance and increasing performance. The current work dealt with the preliminary design of a daysailer with foil technology and hybrid propulsion that allow to combine green and comfortable navigation both under sail and motor and that, when required, can sail in a more performing way by exploiting the foil technology and the thrust of the wind. After having deepened the theory and physics of sailing on foils, a MATLAB code was created to integrate the stability equations that characterize hydrofoil sailboats: connecting the acting forces and allowing to define the dimensions of the geometries, the code was fundamental in speeding up the iterative preliminary design process. The next step was to model the geometry of the hull and the appendages in the CAD environment and, subsequently, the wing movement mechanism so that it could both manage the incidence of the wings and retract the foils when the boat is moored. The hull, profiles, and wings were subsequently placed in a CFD and VPP virtual environment for testing their resistance. Future developments will include a detailed design and the physical prototyping of a first boat for water testing.
Keywords: Green | Hybrid | Hydrofoil | Virtual prototyping
Abstract: The constant growth in global energy demand, and corresponding prices rise, is soaring new engineering methods for reducing energy consumption in manufacturing processes. For decades, industrial robotics have been enabling quality enhancement of end-products by using flexible manufacturing processes, without much concern to energy cost, but now a makeover is happening. Calls for sustainable and green manufacturing processes are being promoted across the globe with the aim to produce more goods and with less consumption. In this paper, a new method is presented focusing on the optimization of energy intake by industrial robots, without the need to change their hardware set and just modifying the trajectory planning of the end-effector. A test case scenario consisting of a robotic cell with 4 pick-and-place manipulators has been set to validate the method. Starting from a pre-scheduled trajectory, robots are moved at the highest speed and acceleration and, by performing the sequenced operations, the optimal trajectories are defined. The goal is to find a trajectory that minimizes the time cycle and the total energy consumption, while avoiding collisions between the robots’ links: comparing the results thereof to those of the pre-scheduled trajectory, noticeable energy saving has been obtained along with possible decrease of the cycle time.
Abstract: One of the main objectives of Industry 4.0 is to build up Smart Factories with improved performance as for productivity, together with lowered maintenance times and costs. In this perspective, Prognostic and Health Management (PHM) is a proactive method to industrial services enhancing maintenance according to the health of the system. PHM entails diagnostic and prognostic engineering tools to recognize the health of the system, and then to choose the prime maintenance actions. The diagnostic tool has to be capable to handle a sizeable volume of data and determine, by means of processing algorithms, the proper set needed for the analysis. The software named MADe can be used as a helpful utility to engineers; it is a model-based toolkit for Reliability, Availability, Maintainability and Safety (RAMS) analysis, capable of optimizing maintenance activities based on the information given by the software, relating to sensor choice and to maintenance strategies. In the PHM framework, the detection of incipient failures is central task of the monitoring the health status of systems that include components sensitive to fatigue or aging. In fact, timely diagnosis allows to schedule maintenance reducing the impact on production outcomes. Based on these considerations, the present paper explains a technique for detecting incipient failures in fatigue sensitive parts, by means of an Equivalent Damage Index (EDI), that can be calculated from the measured signals on the real plant. This procedure is validated, as well as other cutting-edge techniques, to prove its accuracy in detecting incipient breakdowns.
Keywords: Anomaly detection | CBM | Incipient failure | Industry 4.0 | MADe | PHM | Residual Life Estimation | Smart factory
Abstract: Robotic surgery is a set of techniques and technologies used to plan, move, and perform surgery, exploiting the capabilities of robots to overcome human limitations in minimally invasive operations. The use of robots guided by augmented reality has allowed surgeons to improve vision and precision during surgery. Despite the results achieved over the years, there is still a high clinical demand for improvements, which can only be reached using intelligent physical or virtual tools. The present work aims to develop a virtual prototype of robotized bone milling operations, when there is the need to virtually predict operative performance. The proposed model leverages the active connection between Simulink, the well-known numerical tool, and RecurDyn, a commercial CAE solver. In particular, the model parametrization and the simulation process are managed from Matlab, whereas the mechanical system is solved in RecurDyn. After a proper validation of the simulation framework with data taken from the literature, a set of parametric studies has been carried out to investigate the influence of the input parameters on the cutting process.
Abstract: Manufacturing companies to start successful digital transition turn to Industry 4.0. In order to maintain competitiveness on the global market and answer customer demands, industries need to adopt a set of digital technologies to innovate their production processes. The paper aims to propose a methodology that is a step-by-step path to summarize the application phases that a manufacturing company should follow to realize its business digital transformation. The proposed methodology is applied to the case study of an Italian company operating in the luxury leather goods sector. The case study starts from the assessment of the digital maturity of the company. A detailed mapping of the production process and a specific data collection allowed to identify which business processes are particularly critical and should be optimized through the use of digital and enabling technologies. A strategic roadmap is suggested and priorities for resolution are finally defined on the basis of the technological gap and the company’s strategy of enabling actions to mitigate the criticalities.
Keywords: Digital factory | Digitalization | Industry 4.0 | Leather goods sector
Abstract: According to the Industry 5.0 framework, the smart factory should combine digitalization and prediction activities with a greater sustainability and human centrality within working processes. Indeed, the optimization and improvement of the manufacturing processes have to meet cost criteria related to energy consumption, safety, and implementation of new technologies. The development of better and more advanced technologies boosts Human-Robot Interaction (HRI) in the manufacturing processes. However, due to the high number of safety standards about collaborative robotics and the absence of tools and specific design approaches, collaborative robots (cobots) are still widely adopted as traditional industrial robots wasting the huge potential of a properly Human-Robot Collaboration (HRC). The layout designing is a crucial activity in achieving a proper and effective HRC. This work illustrates how to transfer standard-compliant layout solutions towards an interactive three-dimensional (3D) visualization environment in order to enable the digital prototyping of HRC workplaces. The possibility to automatically generate and visualize multiple layout solutions of collaborative workplaces, and then, to simulate the interaction between human and robot, represents one of the most significant tasks during the designing process. HRC workplace layout is designed according to an optimization criterion, by using the full integration of a numerical computing platform with an interactive 3D visualization environment. Then, by means of the variation of the input parameters, the visualization of new layout solutions is enabled in a fast and effective way.
Abstract: Humans are able to communicate by a wide variety of means. Gestures often play an important role in this multimodal communication. In order to also ensure robust interaction between humans and machines, it is important that machines are able to recognize human gestures. This typically requires time-consuming subject tests that limit the number of conditions that can be tested. However, by moving these tests from the physical to a virtual environment, each test condition can be evaluated quickly, eliminating the need for numerous repetitions. The purpose of this work was to validate the use of a virtual test environment in comparison to physical testing. This was done by conducting a subject test and developing a virtual model of the human upper limb. The motion profile of the subject performing a simple gesture was recorded with a visual optical motion capture system and used as input for the newly developed virtual model. Acceleration signals captured with an IMU attached to the subject's right wrist were used as a reference signal and compared to signals simulated by a digital twin of the sensor. The pilot study proved the capabilities of the proposed approach and showed some of its limitations.
Keywords: Digital twin | Human body model | Human gestures | Simulation | Virtual environment
Abstract: The current best-practice in the assembly process of aircraft skin panels involves several manual measurement-fit-adjust quality loops, such as loading part on the assembly frame, measuring gaps, off-loading parts, adding be-spoke shims and re-positioning parts ready for the fastening operation. The consequence is that the aircraft is re-assembled at least twice and therefore this process has been proved highly inefficient. This paper describes the framework developed under the “Integrated Smart Assembly Factory” (ISAF) project in the “Intelligent Factory” specialisation area in Italy. Taking advantage of the emerging tools brought by Industry 4.0 the ISAF framework spearheads innovation in the assembly process of aircraft skin panels by integrating smart and digital technologies such as in-line measurement systems with highly accurate sensors, large-scale physics-based simulations, multi-disciplinary process optimisation and additive manufacturing. ISAF implements a flexible alignment, which combines both rigid rotations/translations and local deformations to account part deformations. The proposed methodology allows predicting and fabricating shims using in-line measurement data with no need to iterate the measurement-fit-adjust quality loops. This will undoubtedly reduce inspection/measurement time and costs, enabling operators to virtually test assembly operations before installation in the field. The results were demonstrated during the assembly process of a vertical stabiliser for commercial aircrafts, and findings showed a significant time saving of 75%.
Abstract: In the context of Industry 4.0, condition-based maintenance (CBM) for complex systems is essential in order to identify failures and mitigate them. After the identification of a sensor set that guarantees the system monitoring, three main problems must be addressed for effective CBM: (i) collection of the right data; (ii) choice of the optimal technique to identify the specific dataset; (iii) correct classification of the results. The solutions currently used are typically data driven and, therefore, the results are variable, as it is sometimes challenging to identify a pattern for all specific failures. This paper presents a solution that combines a data driven approach with an in-depth knowledge of the mechanical system’s behaviour. The choice of the right sensor set is calculated with the aid of the software MADe (Maintenance Aware Design environment), whereas the optimal dataset identification technique is pursued with a second tool called Syndrome Diagnostics. After an overview of such methodology, this work also presents RSGWPT (redundant second-generation wavelet packaged transform) analysis to show different possible outcomes depending on the available sensor data and to tailor a detection technique to a given dataset. Supervised and unsupervised learning techniques are tested to obtain either an anomaly detection or a failure identification depending on the chosen sensor set. By using the described method, it is possible to identify potential failures in the system so to awarely implement the optimal maintenance actions.
Abstract: The importance of training for operators in industrial contexts is widely highlighted in literature. Virtual Reality (VR) is considered an efficient solution for training, since it provides immersive, realistic, and interactive simulations environments promoting a learn-by-doing approach, far from the risks of the real field. Its efficacy has been demonstrated by several studies, but a proper assessment of the operator’s cognitive response in terms of stress and cognitive load during the use of such technology is still lacking. This paper proposes an integrated methodology for the analysis of user’s cognitive states, suitable for each kind of training in the industrial sector and beyond, fostering the human-centred design and manufacturing perspective. The methodology has been assessed using an industrial case study where virtual training is used for assembly of agricultural vehicles. Experimental results highlighted that, with VR additional supportive information, while operators’ errors drastically decrease, the stress increases for complex tasks, due to the greater amount of information to manage. The proposed protocol allows understanding the operators’ cognitive conditions in order to optimize the VR training application, avoiding operators’ stress, mental overload, and improving performance.
Abstract: Artificial limbs can help people missing body parts to restore some of their daily-life activities. However, the user should spend up to a few months to intuitively control the new device. During this period, she/he may suffer pain due to wearing or using the prosthesis inappropriately. This research presents a virtual simulator that allows the user to carry out training sessions for controlling the prosthesis. A set of Surface Electromyographic (sEMG) sensors are used to acquire the signals from user's muscles and send them to a recognition algorithm that interprets the patient's intentions. Simultaneously, the patient observes the response of her/his device on the simulator. Two studies are presented: the first study evaluate the performance of three different recognition algorithms i.e., Linear Discriminant Analysis (LDA), Support Vector Machine (SVM), and Multi-Layer Perceptron (MLP), based on the successful recognition of the patient's intentions. The second study investigates the least number of sEMG sensors to be used, as having less components improves the patient's wearability and decreases the processing time. The developed simulator represents a real prosthetic device, PRISMA hand II. The results showed the superiority of the MLP with 80% of successful recognition when 6-sEMG sensors are used. If a reduced set of gestures is considered (frequently needed by the patient), 90% of successful recognition could be achieved. Less sEMG sensors significantly degraded the performance of the recognition algorithm as only 53.8% of successful recognition could be achieved. All experiments were conducted with the help of a patient with below-elbow amputation.
Keywords: Active prosthetic hand | Biomechatronic application | Multi-Layer Perceptron (MLP) | Pattern recognition | Rehabilitation robotics | sEMG signal processing
Abstract: This paper proposes a System Engineering-based iterative design approach for the DTT HyRMan, an hyper redundant manipulator conceived to perform Remote Maintenance (RM) of the FW modules and inspection tasks in the DTT vacuum vessel. According to the “RFLP” paradigm of the “V-model” (Requirements, Functionalities, Logical and Physical architecture, with the respective test phases), after having defined the manipulator's Requirements and Functionalities, the Logical and Physical architectures have been established. In particular, the current design of hyper redundant manipulator is characterized by twelve joints (two prismatic and ten revolute), with a Planar and a Dexterous Arm. Once defined the ideal operative procedures, the Verification phase of Systems Engineering approach has been carried out. The HyRMan behaviour has been simulated and tested in virtual environment under the in-vessel geometric constraints, to evaluate the overall encumbrance and the remote operations feasibility. The kinematic analyses were performed simulating links and joints as rigid bodies, using the software Delmia in the same Dassault Systèmes V5 platform used for 3D CAD modelling (CATIA V5). Flexibility analyses performed in SimSOFT have confirmed that the HyRMan can be modelled using the rigid body assumption with sufficient confidence, as flexible effects along the length of the links are negligible with the current design of the manipulator. The workflow of actions implemented within the virtual platform and the obtained results are discussed in the paper, further to the evaluation of alternative design solutions in case of reachability or collision avoidance criticalities for the HyRMan.
Keywords: DTT | Flexibility simulation | Hyper redundant manipulators | Kinematic simulations | Remote handling system | Systems engineering
Abstract: Nowadays, manufacturing plants are required to be flexible to respond quickly to customer demands, adapting production and processes without affecting their efficiency. In this context, Industrial Robots (IRs) are a primary resource for modern factories due to their versatility which allows the execution of flexible, reconfigurable, and zero-defect manufacturing tasks. Even so, the control and programming of the commercially available IRs are limiting factors for their effective implementation, especially for dynamic production environments or when complex applications are required. These issues have stimulated the development of new technologies that support more efficient methods for robot control and programming. The goal of this research is to identify and evaluate the main approaches proposed in scientific papers and by the robotics industry in the last decades. After a critical review of the standard IR control schematic, the paper discusses the available control alternatives and summarizes their characteristics, range of applications, and remaining limitations.
Keywords: industrial robots | instruction streaming | open controller | robot control | robot programming | trajectory streaming
Abstract: The manufacturing process may lead non-rigid parts to endure large deformations which could be reduced during assembly. The manufacturing specifications of the single parts should refer to their free state or “as manufactured” state; the functional specifications should instead address the “as assembled” state. Therefore, a functional geometrical inspection requires dedicated fixtures to bring the parts in “as assembled” state. In this paper, through a linearized model that considers fixturing and elastic spring-back, we aim to correlate the functional specification to the manufacturing specifications. The model suggests a hybrid approach called “restricted skin model” that allows to reduce the degrees of freedom considering the form error when relevant. Firstly, the framework is verified in a mono-dimensional test case. Subsequently, it is verified including FEM simulation and actual measurement for two simple assemblies. The results show that the model can correctly interpret the theoretical assembly behaviour for actual applications. The use of the “restricted skin model” approach shows a negligible difference when compared to full FEM simulation with differences of 2.1 · 10−7 mm for traslations and 6.0 · 10−3 deg for rotations. The comparison with actual measurement values showed an error of ±0.2 mm at the assembly features. Furthermore, the linearized model allows a possible real-time application during production that enables to adjust manufacturing specification limits in case of process drifting.
Keywords: Compliant assemblies | Deformable assemblies | Geometrical Product Specification | Linearized model | Restricted skin model | Skin model | Tolerancing
Abstract: Background and objective: The ability to accomplish a consistent restoration of a missing or deformed anatomical area is a fundamental step for defining a custom implant, especially in the maxillofacial and cranial reconstruction where the aesthetical aspect is crucial for a successful surgical outcome. At the same time, this task is also the most difficult, time-consuming, and complicated across the whole reconstruction process. This is mostly due to the high geometric complexity of the anatomical structures, insufficient references, and significant interindividual anatomical heterogeneity. Numerous solutions, specifically for the neurocranium, have been put forward in the scientific literature to address the reconstruction issue, but none of them has yet been persuasive enough to guarantee an easily automatable approach with a consistent shape reconstruction. Methods: This work aims to present a novel reconstruction method (named HyM3D) for the automatic restoration of the exocranial surface by ensuring both the symmetry of the resulting skull and the continuity between the reconstructive patch and the surrounding bone. To achieve this goal, the strengths of the Template-based methods are exploited to provide knowledge of the missing or deformed region and to guide a subsequent Surface Interpolation-based algorithm. HyM3D is an improved version of a methodology presented by the authors in a previous publication for the restoration of unilateral defects. Differently from the first version, the novel procedure applies to all kinds of cranial defects, whether they are unilateral or not. Results: The presented method has been tested on several test cases, both synthetic and real, and the results show that it is reliable and trustworthy, providing a consistent outcome with no user intervention even when dealing with complex defects. Conclusions: HyM3D method proved to be a valid alternative to the existing approaches for the digital reconstruction of a defective cranial vault; furthermore, with respect to the current alternatives, it demands less user interaction since the method is landmarks-independent and does not require any patch adaptation.
Abstract: This article presents the development of a prototype robotic eye-motion system for a novel simulator of ocular and craniofacial trauma that was developed for practical skills training of eye surgeons and first responders. The simulator fills a gap in the ophthalmological training domain, specifically between virtual reality-based systems for cataract and retinal repair and part-task trainers without quantitative measurement capabilities. Combining physical anatomical modules, instrument tracking and embedded sensors with a data acquisition/feedback system in a portable bench-top structure, it offers an alternative to animal- and cadaver-based training. The prototype robotic eye system described includes multiple human eye globe motion features: eye pitch and yaw motion, proptosis, and sensing of applied force to detect pressure/load applied to the globe.
Keywords: Computer-aided design | Medical robotics | Simulation-based-training | Virtual and physical prototyping
Abstract: A leading challenge in the assembly process of aircraft skin panels is the precise control of part-to-part gaps to avoid excessive pre-tensions of the fastening element which, if exceeded, impair the durability and the response under dynamics loads of the whole skin assembly. The current practice is to measure the gap in specific points of the assembly with parts already at their final location, and then be-spoke shims are machined and inserted between the mating components to fill the gap. This process involves several manual measurement-fit-adjust quality loops, such as loading parts on the assembly frame, measuring gaps, off-loading parts, adding be-spoke shims and re-positioning parts ready for the fastening operation—as a matter of fact, the aircraft is re-assembled at least twice and therefore the current practice has been proved highly cost and time ineffective. Additionally, the gap measurement relies on manual gauges which are inaccurate and unable to follow the actual 3D profile of the gap. Taking advantage of emerging tools such as in-line measurement systems and large-scale physics-based simulations, this paper proposes a novel methodology to predict the part-to-part gap and therefore minimise the need for multiple quality loops. The methodology leverages a physics-driven digital twin model of the skin assembly process, which combines a physical domain (in-line measurements) and a digital domain (physics-based simulation). Central to the methodology is the variation model of the multi-stage assembly process via a physics-based simulation which allows to capture the inherent deformation of the panels and the propagation of variations between consecutive assembly stages. The results were demonstrated during the assembly process of a vertical stabiliser for commercial aircraft, and findings showed a significant time saving of 75% by reducing costly and time-consuming measurement-fit-adjust quality loops.
Abstract: This work proposes a geometric approach to inverse kinematics of hyper-redundant manipulators used for remote maintenance of nuclear fusion reactors. The approach is particularly suited to be adopted in real-time human-in-the-loop control strategies involving high-frequency control feedback and requiring safe interaction between the manipulator and the in-vessel environment. The capability of the inverse kinematic method to find a solution for a set of different robot end-effector poses, inside a toroidal environment, was tested on the HyRMan kinematics, i.e. the Hyper Redundant Manipulator developed in the framework of the Divertor Tokamak Test (DTT) project. The simulation tests were aimed at assessing performance of the proposed method in terms of accuracy in the end-effector positioning, computational burden, distance from obstacle, distance from joint angles and torque limits and success rate of the task execution. The achieved results were compared to the ones obtained through an iterative method proposed in literature, i.e. the one based on the computation of the Jacobian pseudo-inverse, demonstrating overall higher performance of the proposed approach and comparable ability to safely avoid obstacles and joint limits.
Abstract: Divertor Tokamak Test (DTT) is the next Italian facility for nuclear fusion research aiming at bringing alternative divertor solutions to a sufficient readiness level to be adopted by the European DEMOnstrating fusion power reactor (EU-DEMO). Since a non-negligible activation is expected on plasma-facing components after DTT shutdown, remote maintenance is mandatory. This work deals with the concept selection for the DTT remote maintenance strategy, in the 2019 reference configuration. First, we present the criteria that we have derived for evaluation of design alternatives. Then, we briefly present the design alternatives developed so far for divertor and first wall remote maintenance. With this regards, three alternatives have been developed for divertor remote maintenance and two alternatives have been developed for first wall remote maintenance. The concept selection process is based on the use of ELIGERE, a decision support tool for concept selection based on the Fuzzy Analytical Hierarchy Process. More than 20 experts from several European institutions have been involved in the concept selection process. The work concludes by presenting the results of the concept selection process, in terms of optimal strategies for divertor and first wall remote maintenance.
Abstract: This article reports the analysis and preliminary design of a passive, wearable, upper limb exoskeleton to support workers in industrial environments in a vast range of repetitive tasks, offering an effective strategy to reduce the risk of injuries in production lines. The system primary purpose is to compensate for gravity loads acting on the human upper limb. The proposed exoskeleton is based on 6 Degrees-of-Freedom (DoFs) kinematics with 5-DoFs for the shoulder joint (two displacements plus three rotations) and 1-DoF for the elbow. Gravity compensation is implemented with passive elastic elements to minimize weight and reduce cost. A detailed analytical tool is developed to support the designer in the preliminary design stage, investigating the exoskeleton kinetic-static behaviour and deriving optimal design parameters for the springs over the human arm workspace. By defining specific functional requirements (i.e., the user’s features and simulated movements), computationally efficient optimization studies may be carried out to determine the optimal coefficients and positions of the springs, thus, maximizing the accuracy of the gravity balancing. Two different solutions for the arrangement of the elastic elements are investigated, and obtained results are validated with a commercial multi-body tool for some relevant movements of the user’s arm.
Abstract: The fourth industrial revolution is characterized by flexible production systems that can respond to the demand for high variability and customization of the product. To maintain the efficiency of the production process, automated and flexible solutions are mandatory. This paper describes an approach to design Virtual Prototypes of robotic cells and support designer in the definition and simulation of the manufacturing system. The identified model is capable of replicating the performance of the cell under different aspects in a holistic manner: geometry, operating logic, performance, and physical behavior. The design approach is demonstrated on a robotic cell composed of two anthropomorphic robots for the flexible process of automatic assembly of mechanical parts. The resulting model proves to be straightforward, accurate and complete.
Abstract: Numerical simulations and Finite Element Analysis (FEA) have currently increased their applications in medical field for making preoperative plans to simulate the response of tissues and organs. Soft tissue simulations, such as colorectal simulations, can be adopted to understand the interaction between colon tissues and surrounding tissues, as well as the effects of instruments used in this kind of surgical procedures. This paper analyses through FEA the interaction between a surgical device and a colon tissue when it is fully clamped. Sensitivity analysis in the respect of the material mechanical behaviour, geometric approximation and the effect of thickness variation are investigated with the aim of setting up a virtual prototype of the surgical operation to aid mentoring and preliminary evaluation via haptic solutions. Through this investigation, the force feedback estimation that is necessary in many virtual-reality applications, may be estimated without discharging nonlinear effects that occur during clamping and that usually cannot be simulated efficiently to guarantee real-time solutions. Results are aligned with experimental data, confirming the reliability and right the set-up of FEA. Through them, the preliminary set-up of a haptic force feedback has been described and simulated through Simulink 3D animation, confirming the feasibility of the concept.
Abstract: Nowadays, restoration is a multidisciplinary work that gathers knowledge and skills from different areas (technical, artistic, historical, architectural, …). In the field of ancient bronze statues, technical knowledge may also concern with materials behaviour and its preservation, surface quality, non-destructive diagnostics for integrity, a better understanding of the manufacturing technology, and of details, sometimes hidden, in not directly accessible sections of the artefact. This knowledge, got from different domains, can support restorers in their decision-making process. In many cases, they summarise it on pictorial views of the artefacts, or on images derived from the 3D model that is experimentally acquired through reverse engineering, to reference information on the interested areas. The aim of this paper is to explore the advantages related to a CAD-based framework able to gather the technical domains involved in the restoration of historical artifacts. Doing so, CAD functionalities and related benefits may be extended to cultural heritage applications as tools oriented for restoration, according to a life cycle perspective of the restorer’s activities and the artefact preservation and fruition. The proposed CAD-based framework has been implemented to manage the investigation for restoration and conservation of bronze statues. The approach has been applied to the Principe Ellenistico, part of the collection of Palazzo Massimo, one of the sites of Museo Nazionale Romano (in Rome). The obtained results show that the CAD-based framework may speed-up the investigation processes without losing accuracy and restorers’ good practices.
Keywords: CAD-CAE | Cultural heritage | Design for restoration | Principe Ellenistico | Virtual prototyping
Abstract: In this work a new approach for the creation of Articulated Total Body (ATB) models for person-specific multi-body simulations is presented, with the main aim of overcoming limitations related to classical multi-ellipsoids ATB models, based on regression equations having only the weight and the height of the subject as input. The new methodology is based on a Statistical Shape Model (SSM), morphable according to up to 24 input parameters: the SSM was obtained from Principal Component Analysis (PCA), applied on a wide database of 3D human scans (CAESAR). The so obtained geometry can be segmented automatically to generate body segments with the respective inertial properties (mass, principal moments of inertia, and centres of mass location). The routine has been tested on a random set of 20 male subjects and the classical multi-ellipsoids models were compared to these in terms of inertial properties and 3D external geometry: the highest differences were registered at the abdomen and the thighs for what concerns the mass (60%), principal moments (75%) and centres of mass (50 mm) properties; the trunk, the shoulder and the calves are the most critical areas for the external geometry (average distance between the anthropomorphic and ellipsoids models equal to 50 mm). A contribution has been made to build person-specific multibody models. This is a valuable method since approximations made by multi-ellipsoidal models have resulted to be relevant at specific body areas, and personalised models can be a support to design and to forensic analyses.
Keywords: 3D parametric human model | Articulated total body | Forensic biomechanics | Multibody analysis | Principal component analysis (PCA)
Abstract: Industry 4.0 (I4.0), through the digitalization and interconnection of manufacturing processes, can offer opportunities to improve production systems' sustainability. Despite the increasing number of scientific review papers related to I4.0 and production sustainability, most approaches and tools for sustainability evaluation lack of a tangible implementation framework. The paper presents a framework that originated from the plant metabolism concept, a simplified version of industrial metabolism. It is based on Energy Material Flow Analysis (EMFA) and Life Cycle Assessment (LCA) tools for production plants' economic and sustainability assessment, using the I4.0 enabling technologies. A Multi-Criteria Decision Making (MCDM) method combines the two sustainability pillars for aiding companies in optimizing their production processes towards a reduction of energy/material flows. The combination of EMFA, LCA and MCDM tools into a plant metabolism-based model is the main novelty of this paper. The framework consists of three main phases. The first phase allows to model the manufacturing system by defining the plant layout, the assets, and the input/output flows. The second phase allows gathering information from the manufacturing plant to assess environmental and economic Key Performance Indicators (KPIs) following the LCA principles. The third phase consists of post-processing results, minimizing specific KPIs for establishing the optimal production scenario. A washing machine plant has been chosen as a case study to demonstrate the proposed method's capability in authentic contexts. Besides, the effectiveness in supporting companies in the analysis, identifying criticalities, and the proper energy and material flows management of production plants has been verified. Plant managers could use this framework for managing the production plans. From the scientific standpoint, the proposed method positively contributes to integrating the existing state of the art studies concerning the I4.0-related framework for the sustainability assessment and energy/material flows minimization of production systems.
Keywords: Energy/material flows | Industry 4.0 | Life cycle assessment | Manufacturing plant | Plant metabolism | Sustainable manufacturing
Abstract: The main aim of this article is to describe the design of a new sensor to study the electromagnetic field portions of gravitational waves. On August 17, 2017, the observation of the gravitational wave event started the era of multi-messenger astronomy. Therefore, new tools and optimal synchronization of the available telescopes are needed. The sensor that is designed is a cross-cutting technology, it is named Crystal Eye: a wide field of view in the energy field from 10 keV to 10 meV with a structure made of pixels. As the detector will be involved in the mission in 2023, the virtual prototype phase needed for optimization and production of the payload has been completed. Particular attention was paid to the results of the FEM analysis carried out to examine and predict the thermal and vibration behavior of the conceived mock-up during the launch phase and under strong temperature variations in the space environment.
Keywords: Detector | FEM | Vibration and thermal analysis | Virtual prototyping
Abstract: One of the main limitations in subject-centred design approach is represented by getting 3D models of the region of interest. Indeed, 3D reconstruction from imaging data (i.e., computed tomography scans) is expensive and exposes the subject to high radiation doses. Statistical Shape Models (SSMs) are mathematical models able to describe the variability associated to a population and allow predicting new shapes tuning model parameters. These parameters almost never have a physical meaning and so they cannot be directly related to morphometric features. In this study a gender-combined SSM model of the human mandible was setup, using Generalised Procrustes Analysis and Principal Component Analysis on a dataset of fifty mandibles. Twelve morphometric features, able to characterise the mandibular bone and readily collectable during external examinations, were recorded and correlated to SSM parameters by a multiple linear regression approach. Then a cross-validation procedure was performed on a control set to determine the combination of features able to minimise the average deviation between real and predicted shapes. Compactness of the SSM and main modes of deformations have been investigated and results consistent with previous works involving a higher number of shapes were found. A combination of five features was proved to characterise predicted shapes minimising the average error. As completion of the work, a male SSM was developed and performances compared with those of the combined SSM. The features-based model here proposed could represent a useful and easy-to-use tool for the generation of 3D customised models within a virtual interactive design environment.
Keywords: Features selection | Mandible | Morphometric measurements | PCA | Predicted shapes | Statistical shape model | Subject-specific model
Abstract: Nowadays, several manufacturing systems are evolving towards a greater collaboration between human and robots. The development of such systems requires integrated design tasks involving many disciplines and domains such as systems engineering, safety analyses and multiphysics. Furthermore, the increasing presence of multiple and structured requirements makes the use of models inevitable during the designing phases and also strongly helpful during other phases of the system life-cycle. Besides, for a better efficiency, there is an increasing demand to have a Digital Twin of the system to be used for different purposes such as design improvements by playing different scenarios, virtual commissioning and controlling maintenance activities. In this paper, we first summarize the research context, the reference methodologies, and the emerging needs for Digital Twin creation. Then, we apply a design approach including Model-Based Systems Engineering (MBSE), Model-Based Safety Assessment (MBSA) and multi-physics modeling for the design of a collaborative workplace for the assembly of Electro-Mechanical Actuators on an aircraft wing. An operational flow to integrate MBSE, MBSA and multi-physics modelling activities is provided. Then, after having identified some relevant scientific barriers, we provide a meta-model for system models integration within a digital twin framework.
Keywords: Collaborative workplace | Digital twin definition | MBSA | MBSE | Multiphysics modelling and simulation | Safety critical systems
Abstract: Enabling technologies that drive Industry 4.0 and smart factories are pushing in new equipment and system development also to prevent human workers from repetitive and non-ergonomic tasks inside manufacturing plants. One of these tasks is the order-picking which consists in collecting parts from the warehouse and distributing them among the workstations and vice-versa. That task can be completely performed by a Mobile Manipulator that is composed by an industrial manipulator assembled on a Mobile Robot. Although the Mobile Manipulators implementation brings advantages to industrial applications, they are still not widely used due to the lack of dedicated standards on control and safety. Furthermore, there are few integrated solutions and no specific or reference point allowing the safe integration of mobile robots and cobots (already owned by company). This work faces the integration of a generic mobile robot and collaborative robot selected from an identified set of both systems. The paper presents a safe and flexible mechatronic interface developed by using MBSE principles, multi-domain modeling, and adopting preliminary assumptions on the hardware and software synchronization level of both involved systems. The interface enables the re-using of owned robot systems differently from their native tasks. Furthermore, it provides an additional and redundant safety level by enabling power and force limiting both during cobot positioning and control system faulting.
Keywords: Human safety | Mbse | Mechatronic system | Mobile cobot | Mobile manipulator | Mobile robot
Abstract: The Servo-Mechanisms (SMs) mounted in industrial robots joints are a major source of positioning accuracy errors. To improve robots precision performance, researchers have been focusing on the development of novel SMs design and control strategies, which need extensive experimental analyses to tune their parameters. In this context, the scope of this paper is double: first, to present the novel experimental apparatus and methods designed to improve the accuracy of the transmission performance evaluation of high dynamics SMs and, secondly, to report and discuss the achieved experimental results. In the first part, a description of the test rig tuning operations is given, primarily focusing on the signals synchronization and on the elimination of the measuring errors caused by the mechanical transmission elasticity and the servomotor torque ripples. Then, control strategies for compensating the torque ripples and input speed errors are defined. It is shown that speed oscillations can be reduced of ≈70% when rotating the servomotor up to 2000 rpm, improving the measurement quality of the reducer performance. In the second part, a set of experiments is carried out to assess the combined effect of input speed and lubricant temperature on the reducer behavior. The system sensitivity to the variation of the input parameters is confirmed by the dynamic lost motion curves, whose mean value equals 16.8″ and 35.4″ when the reducer is operated at its minimum and maximum friction load respectively. At last, the extrapolated harmonic content is used to build a simple mathematical model of the reducer transmission error.
Keywords: Experimental methods | Lubricant temperature | Robot reducers | Servo-mechanisms | Test rig | Torque ripples | Transmission error
Abstract: Intelligent robotic manufacturing cells must adapt to ever-varying operating conditions, developing autonomously optimal manufacturing strategies to achieve the best quality and overall productivity. Intelligent and cognitive behaviors are realized by using distributed controllers, in which complex control logics must interact and process a wide variety of input/output signals. In particular, programmable logic controllers (PLCs) and robot controllers must be coordinated and integrated. Then, there is the need to simulate the robotic cells’ behavior for performance verification and optimization by evaluating the effects of both PLC and robot control codes. In this context, this work proposes a method, and its implementation into an integrated tool, to exploit the potential of ABB RobotStudio software as a virtual prototyping platform for robotic cells, in which real robots control codes are executed on a virtual controller and integrated with Beckhoff PLC environment. For this purpose, a PLC Smart Component was conceived as an extension of RobotStudio functionalities to exchange signals with a TwinCAT instance. The new module allows the virtual commissioning of a complete robotic cell to be performed, assessing the control logics effects on the overall productivity. The solution is demonstrated on a robotic assembly cell, showing its feasibility and effectiveness in optimizing the final performance.
Abstract: Compared to other additive technologies, Wire and Arc Additive Manufacturing (WAAM) offers high deposition rates, flexibility and a larger build volume as well as reduction of material waste. WAAM can be combined with a subtractive technology in hybrid robotic cells to further increase the application scope, thus producing products with improved surface finish where needed. However, there are some open issues that limit this process. So, the main goal of this paper is to review current research developments and provide a framework aimed at manufacturing parts by hybrid cells. A procedure is defined which moves from the evaluation of the designed shapes, their analysis to identify a proper manufacturing sequence until the elaboration of the instructions for the cell automaton controllers. Main WAAM issues are outlined to identify main research directions, and a test case is presented to highlight the process phases.
Keywords: Hybrid manufacturing | Process planning | Robotic cell | Wire and arc additive manufacturing
Abstract: In this work, we propose a framework that can be used for virtual evaluation of Body-Attached Sensor Networks. Normally, the evaluation of Body-Attached Sensor Networks requires numerous subject tests under laboratory conditions. However, since it is difficult to perform the same motion repeatedly without minute deviations, numerous replicate measurements are required to obtain statistically meaningful measurements. To overcome this limitation, we propose the use of virtual environments. These provide both a high degree of flexibility, since a movement can be repeated in the same way each time, and the ability to test many different sensor setups quickly and with little effort. To this end, we modeled the human body parts of interest using the MATLAB tool Simscape Multibody. Digital twins were then implemented in this model to represent real sensors along with their sensor properties at arbitrary locations. This makes it possible to check many different sensor types and their position on the body in a short time without having to perform subject tests. This framework creates a solid basis for the development of effective Body-Attached Sensor Networks.
Abstract: Industry 4.0 is driving the revolution of manufacturing processes by combining innovative technologies and new interaction paradigms among systems and operators. In particular, the layout, tasks and work sequences of assembly lines are designed according to several transdisciplinary Design Principles (DPs), such as process efficiency, product quality, ergonomics, safety and operators' workload. A large variety of simulation software can be employed for evaluations. However, the related ability to assess multidisciplinary factors must be evaluated. The paper aims to provide a framework for guiding the assessment of simulation software in the context of Industry 4.0 assembly lines. Process requirements are first analyzed and mapped to select DPs, prioritized according to design goals by an analytical hierarchy process. Then, suitable simulation software is determined accordingly, and the virtual model is realized. Finally, the possibility of the software to provide meaningful elaborations for the selected DPs is assessed. The framework has been tested on a prototypal Industry 4.0 assembly line composed of automated logistic systems, cobots and systems to guide the execution of tasks. The line has been modeled in Siemens Process Simulate, analyzing the completeness and appropriateness of the functionalities of this software according to the defined DPs.
Keywords: Decision Support Tools | Design Principles | Industry 4.0 | Interactive Simulation for Engineering | Transdisciplinary Engineering
Abstract: Understanding user experience (UX) is essential to design engaging and attractive products, so nowadays has emerged an increasingly interest in user-centred design approach; in this perspective, digital technologies such as Virtual Reality (VR) and Mixed Reality (MR) could help designers and engineers to create a digital prototype through which the user feedback can be considered during the product design stage. This research aims at creating an interactive Digital Twin (DT) using MR to enable a tractor driving simulation and involve real users to carry out an early UX evaluation, with the scope to validate the design of the control dashboard through a transdisciplinary approach. MR combines virtual simulation with real physical hardware devices which the user can interact with and have control through both visual and tactile feedback. The result is a MR simulator that combines virtual contents and physical controls, capable of reproducing a plowing activity close to reality. The principles of UX design was applied to this research for a continuous and dynamic UX evaluation during the project development.
Keywords: Digital Engineering | Digital Twin | Human-centered Design | Mixed Reality | User experience design
Abstract: The ongoing cultural heritage transition process, in which elaborate digitization plans for cultural artifacts are developed to overcome concerns about the objects’ long-term preservation and storage, is now addressing issues for improving and expanding access to digital objects. As a result, new techniques and cutting-edge tools are needed for galleries, libraries, archives, and museums players to deploy and distribute the richness of knowledge housed inside cultural property. Accordingly, the present work provides an overview of the most significant studies addressing the use of innovative technologies for virtual museums and develops some thoughts on how the state of the art is improving as technology progresses. Following a discussion of the most current and significant research on this topic, the article drafts a number of proposals on how the state of the art might be overcome in the near future.
Abstract: Since every structure in the human body can vary, customization is important to choose the most appropriate medical option according to the patient. Total knee arthroplasty (TKA) is a surgical procedure for the knee replacement that has a high rate of patient's dissatisfaction. Indeed, conventional prostheses are based on anthropometric data that accommodate common knees. However, mismatch can occur due to anatomical variations among the individuals. Thanks to the advances in imaging techniques and 3D modeling, it is possible to create customized knee implants starting from medical images. In this context, the present research proposes a methodology to design a customized knee implant taking into account clinical (e.g., prosthesis alignment and surgical cuts) and technical parameters (e.g., materials) that have a direct impact on TKA performance and patient's satisfaction. Changing these parameters, different scenarios have been modeled and simulated to understand the most suitable combination. Finite element analysis (FEA) has been employed to simulate and compare the proposed customized models, changing the different clinical and technical parameters. Stress induced by different combinations of the parameters has been evaluated to choose the optimal solution among the eight proposed scenarios. The optimum is reached with a physiological alignment, with six femoral facets and the ultra-high molecular weight polyethylene (UHMWPE) tibial insert. The implant design maintains the natural joint line and allows preserving more bone. The material is the parameter that mostly influences the stress distribution.
Abstract: Measurement and monitoring systems (MMSs) are intrinsically part of 4.0 and, in particular, of cyber-physical systems (CPSs). However, by introducing the 4.0 enabling technologies into MMSs, also the vice versa can be accomplished, and MMSs can evolve into a cyber-physical measurement system (CPMS). Starting from this consideration, in the present work, a preliminary case study of a CPMS is presented: an innovative robotic platform to be used for measurement systems in confined and constrained remote environments. The proposed system is a soft growing robot that includes a robot base, to be placed outside the remote environments, and a robot body that accesses the site through growth. A pneumatic actuation mechanism enables the controllable growth of the system (through lengthening at its tip), as well as its controllable steering. The system can be equipped with sensors to enable remote monitoring tasks, or can be used to transport sensors in remote locations. The ultimate goal is to achieve a self-adapting, fully-autonomous, reliable and safe system for monitoring applications, particularly useful for the remote inspection of unknown and/or constrained environments.
Abstract: The protection of artistic and cultural heritage is a major challenge due to its peculiarities and its exposure to significant natural hazards. Several methodologies exist to assess the condition of artistic heritage and to protect it from exceptional actions. Moreover, novel digital technologies offer many solutions able to deliver a digital replica of artifacts of interest, so that a reduction in the uncertainties in the analysis models can be achieved. A rational approach to the preservation and protection of artistic heritage is based on traditional approaches supported and integrated by novel technologies, so that qualitative and quantitative indicators of the current condition of artistic heritage can be defined and validated in an interdisciplinary framework. The present paper reports the results of an approach to the maintenance and preservation of art objects housed in a museum complex based on a comprehensive digital path towards a Historical Digital Twin (HDT). A workflow aimed at estimating the stress regime and the dynamic properties of two sculptures, based on the detailed three-dimensional model resulting from a laser scanner survey, is illustrated and dis-cussed. The results highlight the great advantages resulting from the integration of traditional and novel procedures in the field of conservation of artistic assets.
Keywords: 3D simulation | Conservation | Cultural heritage | Digital twin | Laser scanning | Maintenance
Abstract: In this paper we show an overview of the preliminary strategy planned for remote maintenance of neutron–activated and contaminated components of DTT machine, in the 2019 reference configuration. The remote maintenance of such a complex machine has impact on different aspects of the DTT machine: layout of the tokamak hall, vacuum vessel and cryostat structures, in–vessel components. To date, the number and size of vacuum vessel ports as well as the segmentation and size of in–vessel mechanical components of DTT have been established by a compromise between operational and maintenance needs. An extensive multidisciplinary work has been done in deriving the requirements for the DTT remote maintenance strategy. Each vacuum vessel sector is divided into five ports: in the current configuration, the top and bottom divertor cassettes are expected to be removed, respectively, from four lower lateral ports and from four equatorial horizontal ports; the first wall modules at the inboard side are expected to be installed/removed from all the upper ports; the first wall modules at the outboard and upper sides are segmented such that they can be removed from four equatorial horizontal ports. The work describes the current strategies for divertor and first wall remote maintenance systems, as well as a first conceptual design of the remote maintenance equipment of DTT machine.
Abstract: This paper introduces a novel upper limb robotic exoskeleton designed to assist industrial operators in a wide range of manual repetitive tasks, such as tool handling and lifting/moving of heavy items. Due to its reduced size and high maneuverability, the proposed portable device may also be employed for rehabilitation purposes (e.g. as an aid for people with permanent neuromuscular diseases or post-stroke patients). Its primary function is to compensate the gravity loads acting on the human shoulder by means of a hybrid system consisting of four electric motors and three passive springs. The paper focuses on the exoskeleton mechanical design and virtual prototyping. After a preliminary review of the existent architectures and procedures aimed at defining the exoskeleton functional requirements, a detailed behavioral analysis is conducted using analytical and numerical approaches. The developed interactive model allows to simulate both kinematics and statics of the exoskeleton for every possible movement within the design workspace. To validate the model, the results have been compared with the ones achieved with a commercial multibody software for three different operator’s movements.
Abstract: Beam-based Compliant Mechanisms (CMs) are increasingly studied and implemented in precision engineering. Straight beams with uniform cross section are the basic modules in several design concepts, which can be deemed as standard CMs. Their behavioral analysis can be addressed with a large variety of techniques, including the Euler–Bernoulli beam theory, the Pseudo-Rigid Body (PRB) method, the beam constraint model and the discretization-based methods. This variety is unquestionably reduced when considering nonstandard CMs, namely design problems involving special geometries, such as curve/spline beams, variable section beams, nontrivial shapes and contact pairs. The 3D Finite Element Analysis (FEA) provides accurate results but its high computational cost makes it inappropriate for optimization purposes. This work compares the potentialities of computationally efficient modeling techniques (1D FEA, PRB method and chained-beam constraint model), focusing on their applicability in nonstandard planar problems. The cross-axis flexural pivot is used as a benchmark in this research due to its high configurable behavior and wide range of applications. In parallel, as an attempt to provide an easy-to-use environment for CM analysis and design, a multi-purpose tool comprising Matlab and a set of modern Computer-Aided Design/Engineering packages is presented. The framework can implement different solvers depending on the adopted behavioral models. Summary tables are reported to guide the designers in the selection of the most appropriate technique and software framework. Lastly, efficient design procedures that allow to configure nonstandard beam-based CMs with prescribed behavior are examined with two design examples.
Abstract: This paper reports about the design of a bio-inspired compliant wrist, whose mobility (i.e. ulnar-radial deviation and flexion-extension) has been realized by employing two pairs of contact-aided Cross-Axis Flexural Pivots (CAFPs), actuated via remotely-placed servo-motors and tendon transmissions. The human wrist behaves differently when deflecting in clockwise or anticlockwise direction, both in terms of maximum angular deflection and passive stiffness. The device proposed hereafter aims at mimicking such natural asymmetry, while withstanding unexpected external loads. In order to fulfill these requirements, two contacts are included: (i) a pure rolling contact (named passive contact), achieved via a cam mechanism guiding the CAFP deflection and ensuring the wrist resistance to compressive loads; (ii) a purposely shaped contact pair (named active contact), acting on one beam of the CAFP so as to increase its stiffness. The design procedures and tools specifically developed for the wrist optimization are described. In the first step, a CAFP shape optimization is performed, followed by the synthesis of the active contact pair. In the second step, the centrodes are computed and then used to generate the passive contact profiles. At last, the third step focuses on the definition of the tendons routing. To prove the validity of the numerical models, a physical prototype of the wrist is produced and tested. Direct comparisons between simulations and experiments confirm the efficacy of the proposed design method.
Abstract: This article reports the preliminary analysis and design of a novel 6 degrees of freedom, passive, upper limb exoskeleton for industrial applications. The aim is to conceive a wearable device to support workers in a vast range of repetitive tasks, offering an effective strategy to reduce the risk of injuries in production lines. The exoskeleton primary purpose is to compensate for the gravity loads acting on the human upper limb via the action of five springs. By reaching the static balancing through the use of passive elements only, several advantages in terms of reduced weight and cost can be provided. In this scenario, a detailed analytical approach has been developed to study the exoskeleton statics and synthesize the springs within the human upper limb workspace. In particular, a 3R balancer is designed for the exoskeleton shoulder joint and a set of computationally efficient optimization studies are carried out to determine the optimal coefficients and positions of the springs. The obtained results have been validated with a commercial multibody tool.
Abstract: Servo-Actuated Mechanisms (SAM) are capable of improving the flexibility and reconfigurability of modern automatic machines. On one hand, as compared to fully mechanical drives, SAM may suffer from non-negligible positioning inaccuracies, whose effect can become unacceptable in case of undesired part deformations during high dynamic motions. On the other hand, it may be the case that parts of the system are purposely designed to provide an highly compliant behaviour, so as to potentially increase the device safety in case of interaction with humans. In both cases, practical strategies to reduce the SAM positioning errors are necessary. As a possible solution to such issue, in this paper, an integrated approach to improve the accuracy of a partially compliant SAM in position-controlled tasks is described. The method exploits a multi-software framework comprising Matlab and RecurDyn, namely a commercial Computer-Aided Engineering (CAE) tool that can be used to simulate the motion of systems comprising both rigid and flexible bodies. Starting from an initial, sub-optimal, motion law of the input link, a trajectory optimizer iteratively runs the CAE solver and automatically computes an optimal, compensated, position profile. The obtained results show that the method may represent a useful tool for analyzing/designing partially compliant SAM, whenever analytical models are either too complex or not readily available.
Abstract: Principal components analysis is a powerful technique which can be used to reduce data dimensionality. With reference to three-dimensional bone shape models, it can be used to generate an unlimited number of models, defined by thousands of nodes, from a limited (less than twenty) number of scalars. The full procedure has been here described in detail and tested. Two databases were used as input data: the first database comprised 40 mandibles, while the second one comprised 98 proximal femurs. The “average shape” and principal components that were required to cover at least 90% of the whole variance were identified for both bones, as well as the statistical distributions of the respective principal components weights. Fifteen principal components sufficed to describe the mandibular shape, while nine components sufficed to describe the proximal femur morphology. A routine has been set up to generate any number of mandible or proximal femur geometries, according to the actual statistical shape distributions. The set-up procedure can be generalized to any bone shape given a sufficiently large database of the respective 3D shapes.
Keywords: 3D model generator | Comparative anatomy | Mandible anatomy | Mesh morphing | PCA | Proximal femur anatomy | Stochastic bone models
Abstract: Hybrid and full electric automotive market is strongly increasing the demand for power semiconductor modules. With respect to discrete packages, manufacturing of power modules is more complex and new process parameter, such as module deformation (warpage), assumes a key role for a robust design and to guarantee reliable application. The aim of this paper is to study the warpage behaviour during power module assembly flow by means of dedicated warpage measurement at different process steps. Once highlighted the most impacting process for warpage, a finite element model has been developed to reproduce phenomenology, predicting the induced deformation.
Keywords: Finite element modeling | Manufacturability | Planarity | Power module | Warpage measurement
Abstract: Belt drives are commonly used in various types of transmissions to link two or more rotating shafts. In order to transmit the motion, an effective grip on the pulley has to be set by imposing a pre-load on the belt. Moreover, the dynamics of the system is strongly affected not only by the geometrical and inertial properties but also by the imposed belt tension force as a functional parameter affecting the vibration characteristics. In the present work, it is presented an integrated methodology, experimental and numerical, to determine the dynamic behaviour of a water pump drive in a high-performance internal combustion engine.
Keywords: Belt | Internal combustion engine | Multibody model | Natural frequency | Vibration modes | Water pump transmission drive
Abstract: The massive presence of plastic in the oceans, both in the form of large debris and micro-plastic, is raising global concern due to its severe effects on the marine environment and fauna, causing loss of biodiversity and potentially threatening human health. Even though this is due to poor waste management, the great production and consumption of single-use plastic is a significant exacerbating factor. Despite policies and bans can be effective measures, there is also the need to raise consumers’ awareness, so they can make more sustainable choices when purchasing, using, and dismissing products. In particular, educating young citizens and encouraging them to engage in pro-environmental behaviors is a fundamental task to reach this goal. In this work, we present Contact from the future, a digital game on plastic pollution for children, to create awareness and stimulate pro-environmental behaviors, discussing the definition of objectives and requirements, as well as the design and development of the application.
Keywords: Human computer interfaces/interactions | Virtual and augmented reality environments | Virtual prototyping
Abstract: Obstructive sleep apnea syndrome (OSAS) is a sleep disorder that causes pauses in breathing or periods of shallow breathing during sleep. Mandibular advancement devices (MADs) represent a non-invasive treatment for OSAS that has had the highest development in recent years. Nevertheless, literature has not primarily investigated the effects of mandibular advancement. This paper presents a finite element method numerical simulation model for evaluating the stress/strain distribution on the temporomandibular joint (TMJ) and periodontal ligaments caused by advancement devices used for the treatment of OSAS. Results highlight that the mandible lift phase generates significant stress values on TMJ, which cannot be neglected for extended usage of MADs. Furthermore, mandible molar teeth are more loaded than incisor ones.
Abstract: Reducing energy/resource consumption in production processes can significantly improve the environmental performance of manufacturing systems. This paper proposes a sustainable manufacturing method and tool and describes its application in a mechanical engineering company which produces automotive components. The tool allows to map the processes/activities and the related resources consumed, assess the efficiency through specific key performance indicators, identify process criticalities and thus set mitigation or improvement strategies.
Keywords: Energy efficiency | Energy management | Resource consumption | Resource mapping | Sustainable manufacturing tool
Abstract: The ITER Radial Neutron Camera is a diagnostic whose objective is measuring neutron emissivity and fusion power density through an array of detectors placed in collimating structures. The RNC is composed of two subsystems (In-Port RNC and Ex-Port RNC), located in the Equatorial Port 01 of the ITER tokamak. Although the measurements from the RNC are required for ITER D-T phase, its In-Port components must be ready for Assembly phase 2. Consequently, the two subsystems will be delivered at different times. At the current status of the design the In-Port RNC interfaces must be defined, if not fully specified, in order to allow for the subsystem integration in the Port Plug. A thorough assessment of the interfaces of the subsystem with all the diagnostics, plants and services in the port has been made, taking into account the concurrent development of the Equatorial Port 01 and the progress in the design of some of the subsystem components that may affect the identification of interfacing Plant Systems. This paper deals with the process that led to definition of the internal and external interfaces of the In-Port RNC, highlighting the main issues and the solutions adopted to perform integration within the Equatorial Port Plug 01.
Keywords: Integration | Interfaces | Iter diagnostics | Radial neutron camera
Abstract: Latest trends and developments in digital technologies have enabled a new manufacturing model. Digital systems can monitor, optimize and control processes by creating a virtual copy of the physical world and making decentralized decisions. This paradigm relies on the development of a digital counterpart, the Digital Twin, for each production resource taking part to the whole manufacturing process. Although real applications of Digital Twin may differ in technical and operational details, in the past years, a huge effort has been done in order to identify and define focal functionalities and properties, as well as main challenges for the practical implementation within real factories. This paper is intended to review and analyse principles, ideas and technological solutions of the Digital Twin vision for production processes focusing on the practical industrial implementation. The purpose of this document is therefore to summarize the current state-of-art on Digital Twin concepts, and to draw their up-to-date state for application and deployment in real industrial processes. Finally, future directions for further research are discussed.
Keywords: Digital twin | digital twin industrial architecture | industrial implementation | industry 4.0 | smart manufacturing
Abstract: The quality and acoustic comfort of agricultural tractor cabins are nowadays highly valued by the market. For this reason, tractor manufacturers are more and more interested in improving the behaviour of their vehicles also from an acoustics point of view. A tractor cabin is an unusual environment, with a space mainly developed in the vertical direction, characterised by a relatively small volume of air and surrounded by windows, which can be considered as large reflecting surfaces. This feature causes strong standing waves that, when coupled with an acoustic source, can generate high sound pressure levels resulting in reduced comfort for the driver. This paper investigates, through measurements and simulations, the low frequency acoustic behaviour of a small tractor cabin. The technique adopted for the measurements is based on a multiple transfer function analysis. Measured frequency response functions are processed for the cabin's acoustic mode parameters. The results of the experiments are validated through a finite-element model allowing the reconstruction of the sound pressure contours inside the volume and further analyses.
Keywords: Finite element | Sound absorption | Standing waves | Tractor cabin | Transfer function
Abstract: This paper describes a mechanics–based framework for virtual prototyping of soft robots, i.e. robots with deformable bodies and flexible joints. The framework builds on top of the screw theory, and uses geometrically exact nonlinear beam models for describing the behavior of deformable bodies, as well as the finite element method for space discretization. The computer implementation of this framework results in SimSOFT, a physics engine for soft robots. The capabilities of the framework are illustrated with one general example, an articulated chain of rigid and soft links connected through rigid and flexible joints. Furthermore, several case studies are shown for industrial and medical applications.
Abstract: Within the era of smart factories, concerning the ergonomics related to production processes, the Digital Twin (DT) is the key to set up novel models for monitoring the performance of manual work activities, which are able to provide results in near real time and to support the decision-making process for improving the working conditions. This paper aims to propose a methodological framework that, by implementing a human DT, and supports the monitoring and the decision making regarding the ergonomics performances of manual production lines. A case study, carried out in a laboratory, is presented for demonstrating the applicability and the effectiveness of the proposed framework. The results show how it is possible to identify the operational issues of a manual workstation and how it is possible to propose and test improving solutions.
Keywords: Digital Twin | Ergonomics | Manufacturing | Production process
Abstract: The research on the use of virtual reality (VR) in the design domain has been conducted in a fragmentary way so far, and some misalignments have emerged among scholars. In particular, the actual support of VR in early design phases and the diffusion of practices involving VR in creative design stages are argued. In the present paper, we reviewed VR applications in design and categorized each of the collected 86 sources into multiple classes. These range from supported design functions to employed VR technologies and the use of systems complementing VR. The identified design functions include not only design activities traditionally supported by VR, such as 3D modelling, virtual prototyping, and product evaluation, but also co-design and design education beyond the early design phases. The possibility to support early design phases by means of VR is mirrored by the attention on products that involve an emotional dimension beyond functional aspects, which are particularly focused on in virtual assemblies and prototypes. Relevant matches between VR technologies and specific design functions have been individuated, although a clear separation between VR devices and supported design tasks cannot be claimed.
Keywords: 3D modelling | Co-design | Early design phases | Engineering design | Industrial design | Product design | Product evaluation | Technological development | Virtual prototyping | Virtual reality
Abstract: The aim of this research is to develop patient-specific 3D mandible models, based on a limited number of measurements taken on the patient. Twenty Computed Tomography scans were used to build the respective 3D cad models of the mandible. Fifteen of these models were given as an input to a Principal Component Analysis software, and eight ‘principal’ mandible morphologies were produced. The following step was to identify the most efficient landmarks to ‘weight’ these morphologies when building a patient-specific model. Two further mandible computed tomography scans (a ‘normal’ mandible and a ‘severely resorbed’ one) were used to test the full procedure and to assess its accuracy. The accuracy of the 3D morphed surface resulted to range between 0.025 and 3.235 mm for the ‘normal’ mandible and between 0.012 and 1.149 mm for the ‘severely resorbed’ one having used eight landmarks to morph a ‘standard’ mandible. This work demonstrates how patient-specific models can be obtained registering the position of a limited number of points (on panoramic x-ray or on the physical model), reaching a good accuracy. This allows performing patient-specific planning and numerical simulations even for those cases where a computed tomography scan would not be available. In fact, this procedure can be interfaced with mesh morphing algorithms to automatically build finite element models. The accuracy of the procedure can be further improved, widening the mandibles computed tomography scans database and optimizing landmarks position.
Keywords: Morphing | Patient-specific models | Principal Component Analysis
Abstract: Eco-design strategies aim to integrate environmental considerations into product design and development. Several regulations, directives and standards have been issued on this topic during last years. In particular, European Directive (2009/125/EC) establishes the eco-design requirements related to domestic and commercial kitchen appliances (e.g. cookers, hobs, grills). The present paper focuses on the virtual product eco-design of domestic induction heating cookers, which are becoming one of the leading cooking systems due to their advantages, e.g. energy efficiency, rapid heating, cleanliness, and user safety. The adoption of numerical analysis tools for the simulation of cooktops use phase, based on thermodynamic modelling, allows to provide useful information regarding the performance of cooking system at each phase of cooking. The paper provides a progress beyond the state-of-art on thermodynamic models for induction hob simulation considering interaction between the cooktop and the pot in the work environment. The goal of the paper is therefore to propose a methodology able to support designers in evaluating heating performances of induction cooking appliances, early in the design phases, through a virtual and multi-physical product model. Thermodynamic performances are determined by measuring several parameters and reproducing the energy consumption test by the mean of a virtual prototyping tool. Results highlight how the proposed model is adherent with the real tests following a specific standard in this sector with a maximum deviation of 3.2% considering the different cooking pot sizes.
Abstract: Generally, comfort may be defined as the “level of well-being” perceived by humans in a working environment. The state-of-the-art about the evaluation of comfort/discomfort shows the need for an objective method to evaluate the “effect in the internal body” and “perceived effects” in main systems of comfort perception. Some medical studies show that each human joint has its own natural Rest Posture in which human muscles are completely relaxed or at the minimum strain level. Basing on this assumption, in other studies postural comfort curves for each Degree of Freedom of human upper and lower-limbs joints have been studied and CaMAN software has been developed to have a direct interface with these curves. In this paper, the upper limbs’ postural comfort curves have been compared with the results gained by the biomechanics virtual simulation built on ANYBODY Software. A detailed study has been conducted on the upper body muscular activation during upper limbs movement with and without load. Postures have been analysed both by ANYBODY and CaMAN in order to correlate the postural (dis)comfort perception with the calculated muscular activity.
Keywords: ANYBODY software | Human Man Interface simulation | Postural comfort
Abstract: A robust machine health state recognition tool is a pillar for condition-based maintenance and Deep Learning approach finds its natural application in such a context. This paper investigates the recognition of machine failures by image classification through a convolutional neural network in a condition-based maintenance environment. The case study involves a refrigerator for large retail establishments. Experimental measures, while the machine is approaching failure, are difficult to be collected, especially in the quantity needed for training and testing the neural network. For this reason, a digital twin of the asset has been created to simulate the behavior of the machine and generate as many data as needed: physically-based models of the machine and failure modes have been included and the simulated behavior has been tuned by using experimental data. Finally, it has been employed to generate signals that, translated into images, test the suitability of the neural network.
Keywords: Condition based maintenance | Digital twin | Image classification | Neural network
Abstract: An innovative airport control tower concept based on the use of modern augmented reality technologies has been developed and validated by means of human-in-the-loop experiments in a simulated environment. An optical-based augmented reality interface underpins the proposed concept that consists in providing air traffic control operators in the airport control tower with complete head-up information, as opposed to the current mix of information retrieval through both head-up real view and head-down interfaces. Specific measurement of the time spent by the operator working in either head-up or head-down position, show that the proposal has a clear effect in stimulating the air traffic control operator to work in a head-up position more than in a head-down position, with positive effects on his/her situational awareness and perceived workload, especially when dealing with low visibility conditions operational scenarios.
Abstract: The implementation of symbiosis approaches is recognized as an effective industrial strategy towards the optimization of resource exploitation and the improvement of collaboration in the context of Industry 4.0. An industrial system can be considered as a complex environment in which material, energy, machine, and human resources should cooperate towards the improvement of efficiency and the creation of value. According to this vision, the paper presents a detailed literature review about the existing symbiosis approaches: (i) industrial symbiosis models, which mainly aim at the sharing of resources among different companies, and (ii) human symbiosis, which focuses on how to effectively strengthen the synergy among humans and machines. Strengths, weaknesses and correlations among the most common symbiosis approaches are analysed and classified. Finally, the existing symbiosis models are related with the pillars of the Industry 4.0 paradigm, in order to understand what should be the future directions of research in the context of collaborative manufacturing.
Keywords: collaborative manufacturing | human symbiosis | industrial symbiosis | Industry 4.0
Abstract: Simulation tools for liquid composite molding processes are a key to predict and solve manufacturing issues of composite materials. Numerical processes are commonly used to analyse and predict mould filling, considering also resin cure and exothermic reactions. These evaluations are usually performed through dedicated software tools that require highly specialized operators and purchasing costs. The present study relates to a multi-objective optimization approach for evaluating the effect of different process parameters of the resin transfer molding (RTM) process using a multi-purpose tool. Starting from a simple case, useful for analysing the effect of mesh type and size on the simulations, and then increasing the complexity of the models, virtual simulations have been validated through real tests. Afterward, this approach has been used for the optimization of the RTM process for the manufacturing of an automotive component. Gate positions, injection pressure and resin temperature have been optimized using finite-volume analysis with a multi-objective genetic algorithm. Finally, the parameters have been used in real experiments in order to validate the efficiency and the reliability of multi-purpose tool in simulating RTM processes.
Abstract: In this paper, an original approach for the virtual prototyping of composite pressure tanks is proposed. The main tests to be conducted for the homologation of the vehicle tank is the burst pressure, which is a quasi-static test. This method aims to reduce the finite element model development time by the integration between the computational software MATLAB and the FEA tool Abaqus. Since the dome shape has fundamental influence on the mechanical performances of the composite pressure vessel, the presented procedure allows the designer to quickly import the suitable dome geometry into Abaqus, without the need of going through CAD software. The first step of the method here reported is the definition of all the geometric and operational parameters necessary to the construction of the dome meridian profile. The second step is to enter those parameters in a MATLAB script, which is able to integrate the dome profile differential equation, to generate the whole tank profile and to import this profile into Abaqus. Once the geometry has been imported, a FE model of the high-pressure vessel can be built and virtual simulations can be performed. This approach could be implemented in a dome optimization process to find which dome meridian profile gives the best tank performances.
Abstract: Intramedullary nails constitute a viable alternative to extramedullary fixation devices; their use is growing in recent years, especially with reference to self-locking nails. Different designs are available, and it is not trivial to foresee the respective in vivo performances and to provide clinical indications in relation to the type of bone and fracture. In this work a numerical methodology was set up and validated in order to compare the mechanical behavior of two new nailing device concepts with one already used in clinic. In detail, three different nails were studied: (1) the Marchetti-Vicenzi's nail (MV1), (2) a revised concept of this device (MV2), and (3) a new Terzini-Putame's nail (TP) concept. Firstly, the mechanical behavior of the MV1 device was assessed through experimental loading tests employing a 3D-printed component aimed at reproducing the bone geometry inside which the device is implanted. In the next step, the respective numerical model was created, based on a multibody approach including flexible parts, and this model was validated against the previously obtained experimental results. Finally, numerical models of the MV2 and TP concepts were implemented and compared with the MV1 nail, focusing the attention on the response of all devices to compression, tension, bending, and torsion. A stability index (SI) was defined to quantify the mechanical stability provided to the nail-bone assembly by the elastic self-locking mechanism for the various loading conditions. In addition, results in terms of nail-bone assembly stiffness, computed from force/moment vs. displacement/rotation curves, were presented and discussed. Findings revealed that numerical models were able to provide good estimates of load vs. displacement curves. The TP nail concept proved to be able to generate a significantly higher SI (27 N for MV1 vs. 380 N for TP) and a greater stiffening action (up to a stiffness difference for bending load that ranges from 370 Nmm/° for MV1 to 1,532 Nmm/° for TP) than the other two devices which showed similar performances. On the whole, a demonstration was given of information which can be obtained from numerical simulations of expandable fixation devices.
Keywords: biomechanical stability | experimental tests | flexible bodies | intramedullary nails | Marchetti-Vicenzi nail | multibody analysis | stiffness
Abstract: Robot geometrical calibration aims at reducing the global positioning accuracy of a robotic arm by correcting the theoretical values of the kinematic parameters. A novel method for the geometrical calibration of robotic arms used in industrial applications is proposed. The proposed approach mainly focuses on the final positional accuracy of the robotic tool center point (TCP) when executing an industrial task rather than on the accurate estimation of the kinematic parameters themselves, as done so far by many calibration methods widely discussed in literature. A real industrial use-case is presented, and the steps of the proposed calibration procedure for the robotic arm are described. Experimental methodology and results for the identification of geometrical parameters are also discussed. A practical validation of the final positional accuracy of the robotic arm (after kinematic calibration) was performed, and experimental results validated the proposed procedure, proving its feasibility and effectiveness in the considered industrial scenario.
Abstract: Deburring operations are critical to automate when high quality is required, due to the unpredictable presence and variable thickness of burrs that necessitate singular optimized process planning. Industrial anthropomorphic manipulators could effectively perform high quality deburring operations, but still lack the intelligence needed to generate quality and time-optimal deburring cycles. This paper presents a novel architecture of Zero Defect intelligent deburring robotic cells. Vision systems and metrological sensors allow the identification of the burrs and the overall quality and pose of the workpiece, while a novel model-based supervisory control, based on a digital twin, automatically calculates the optimal sequence of operations and working parameters needed to achieve the desired quality, generating also the PLC and robot controllers validated code to perform each task. Finally, the prototype of the proposed Zero Defect intelligent deburring cell has been developed.
Keywords: Digital twin | Engineering methods | Industry 4.0 | Robotic manufacturing | Virtual prototyping | Zero defect manufacturing
Abstract: Industry 4.0 leverages Cyber Physical Production Systems (CPPS) that use IoT (Internet of Things) communication and ubiquitous computing to optimize and integrate synergistically manufacturing processes and industrial business. This increased computational and communication capability allows to dynamically interact with the physical environment providing higher performance leading the fourth industrial revolution. The benefits generated by the involvement of the TOGAF Framework in the most varied organizational models were previously discussed in the literature in a broad way, different from the application of IoT architecture, recently studied and applied in the industrial branch. Therefore, no IoT application activities based on the TOGAF structure in manufacturing processes were identified. To explore this interactivity in IoT based manufacturing systems, this paper seeks to investigate how industrial IoT application architectures are built and correlate them with the framework TOGAF (The Open Group Architecture Framework). The development of the article is defined in three steps: (i) to review the literature within the industrial context in order to consolidate the information and address different representations of the study in question to confirm the gap presented earlier; (ii) to verify the various ways to structure the information for IoT applications and correlate them with the TOGAF framework; and (iii) to elaborate a consistent critical analysis from the addressed points.
Keywords: Architecture | Internet of things | IoT | TOGAF
Abstract: The electrification of utility vehicles represents a promising solution to reduce the emissions in the urban context. Differently from traditional vehicles, they operate intermittently and generally follow routine driving cycles. In this paper, we model a 15-kW electric utility vehicle, adopting a backward-looking approach, widely used in literature to estimate the range of electric cars. The model requires a limited number of data, either supplied by the vehicle manufacturer or found in literature, as in case of the induction motor/generator efficiency and of the battery Peukert coefficient. The model can be used to assess the possibility of the vehicle to complete an assigned mission, as well as to optimize the vehicle's design and architecture. The model is validated on GPS data obtained through an experimental campaign where the electric utility vehicle was driven to depletion considering different routes, including the effect of slopes. A satisfactory correspondence with the experimental data was observed with maximum difference in the simulated average energy consumption lower than about 8%. Results of the simulations show that the range of the electric utility vehicle is about 110 km on urban flat cycle while it significantly reduces when slopes are included in portions of the routes.
Abstract: The main sources of sound emitted by vehicles are the engine and the rolling noise produced by the tires. In case agricultural tractors are considered, the engine and the transmission are responsible of the main emissions since they often work in the fields on soft ground at low speeds. This work focuses on the combined acoustic and mechanical development of a new exhaust system for an existing agricultural tractor, with the aim of providing a product with improved acoustic performances and a neater design. The host vehicle is equipped with a 300 hp diesel engine which can be particularly noisy at low rpm, with a further constraint being the “under the bonnet” available volume to fit the system into. The existing exhaust system is the baseline for the engineering process. The acoustic design is carried out by a 1D simulation software based on an electro-acoustic analogy, while the design modelling is performed by using Solidworks® 3D CAD. After the design stage a prototype has been manufactured and tested at the MWL/KTH laboratory. The engineering process gave the product a cleaner design and allowed to identify feasible solutions ensuring increased sound attenuation performances.
Abstract: Meeting the demands of Industry 4.0 and Digital Manufacturing requires a transformative framework for achieving crucial manufacturing goals such as zero-defect production or right-first-time development. In essence, this necessitates the development of self-sustainable manufacturing systems which can simultaneously adapt to high product variety and system responsiveness; and remain resilient by rapidly recovering from faulty stages at the minimum cost. A Closed-Loop In-Process (CLIP) quality control framework is envisaged with the aim to correct and prevent the occurrence of quality defects, by fusing sensing techniques, data analytics and predictive engineering simulations. Although the development and integration of distributed sensors and big data management solutions, the flawless introduction of CLIP solutions is hindered specifically with respect to acquiring and providing in-process data streams at the required level of: (1) veracity (trustworthiness of the data); (2) variety (types of data generated in-process); (3) volume (amount of data generated in-process); and, (4) velocity (speed at which new data is generated in-process) as dictated by rapid introduction and evolution of coupled system requirements. This paper illustrates the concept of the CLIP methodology in the context of assembly systems and highlights the need for a holistic approach for data gathering, monitoring and in-process control. The methodology hinges on the concept of “Multi-Wave Light Technology” and envisages the potential use of light-based technology, thereby providing an unprecedented opportunity to enable in-process control with multiple and competing requirements. The proposed research methodology is presented and validated using the development of new joining process for battery busbar assembly for electric vehicles with remote laser welding.
Abstract: A critical point for manufacturing companies has always been the optimization of their production processes to increase the productivity and minimize the related costs, chasing an efficiency principle. Thanks to advent of Industry 4.0 (I4.0) era, some technologies, perceived as far away few years ago, now can be reached by everyone. The use of these technologies allows factories to acquire and evaluate their production data (and much more) and carry out complex analyses in short time making possible the improvement of the production processes. Aim of this paper is to propose a methodological framework in which, starting from an existing process, where workers and machines have already been assigned to each station of a production line, the use of Industrial Internet of Things (IIoT) devices, such as wearable ones, allows to carry out analyses of the performance parameters of the production lines by means of an event-based simulation. In this way it is possible to evaluate if improvements are possible by re-balancing or re-scheduling the line. A case study, regarding a manual task of a real manufacturing production line, is presented to demonstrate the applicability and the effectiveness of the described framework.
Keywords: Internet of Things | Line balancing | Methodological framework | Wearable devices
 Miccichè G., Ascott M., Bakic A., Bernardi D., Brenosa J., Coloma S., Crofts O., Di Gironimo G., Ferre M., Fischer G., Ibarra A., Karap A., Kiss I.G., Kunert C., Lorenzelli L., Mitchell G., Mittwollen M., Pagani P., Papa S., Porempovics G., Tadic T., Matyas T.,
The remote handling system of IFMIF-DONES, Fusion Engineering and Design,
Abstract: The International Fusion Materials Irradiation Facility-DEMO Oriented Neutron Source (IFMIF-DONES) consists of complex systems and massive components that need to be on site assembled and maintained. For several of them it is required to perform maintenance, inspection and monitoring tasks over many years in a hostile environment and in efficient, safe and reliable manner. The maintenance of IFMIF-DONES’ systems and components, located mainly in the Test Systems (TS), in the Lithium Systems (LS) and in the Accelerator Systems (AS), is classified as a Remote Handling (RH) Class 1st activity and as such is considered a crucial and essential activity whose success will strictly depend on the IFMIF-DONES RH capability. According to this, a Remote Handling System (RHS) for IFMIF-DONES, which comprises the whole set of Remote Handling Equipment and tooling for the execution of maintenance tasks, has been designed. A wide range of technologies is involved: special cranes, manipulator arms, lift interface frames, special cameras, control systems and virtual reality. In this paper an overview on status of the design of the main robotic systems and tooling of the RHS of IFMIF-DONES, including design requirements, functions and maintenance tasks to be performed, is given.
Abstract: Soft continuum robots provide high dexterity in constrained spaces, while guaranteeing a compliant interaction with the surrounding environment. Over the last years, they have been used to improve many manipulation tasks, going from maintenance, inspection and repair in industrial-related environments to minimally invasive surgery in the medical field. This paper investigates the use of soft continuum robots for remote measurement tasks, and focuses on the following application scenarios where they have already demonstrated their benefits: space, aerospace, nuclear, marine and medical fields. The limitations of existing applications and perspectives of future directions are also discussed.
Abstract: In this paper, a novel concept of robotic manipulator is developed for direct additive manufacturing on non-planar surfaces. The application scenario is the metal coating of the internal surface of radome systems, using frequency selective surface patterns. The manipulator is presented from the design, modeling, and control point of view. It is developed following an application-driven approach, meaning that the requirements from the application and the additive manufacturing technology are translated into the design specifications of the robotic system. Simulation results demonstrate that the proposed control strategy based on a decentralized architecture is satisfactory to accurately control the motion of the robotic mechanisms along the trajectory foresees by the direct additive manufacturing task.
Abstract: At present, energy consumption strongly affects the financial payback period of industrial robots, as well as the related manufacturing process sustainability. Henceforth, during both design and manufacturing management stages, it becomes crucial to assess and optimize the overall energy efficiency of a robotic cell by means of digital manufacturing tools. In practice, robotic plant designers and managers should be able to provide accurate decisions also aimed at the energy optimization of the robotic processes. The strong scientific and industrial relevance of the topic has led to the development of many solutions but, unfortunately, state of the art industrial manipulators are equipped with closed controllers, which heavily limit the feasibility and performance of most of the proposed approaches. In light of the aforementioned considerations, the present paper presents a novel simulation tool, seamlessly interfaced with current robot offline programming tools used in industrial practices, which allows to automatically compute energy-optimal motion parameters, thus reducing the robot energy consumption, while also keeping the same productivity and manufacturing quality. The main advantage of this method, as compared to other optimization routines that are not conceived for direct integration with commercial industrial manipulators, is that the computed parameters are the same ones settable in the robot control codes, so that the results can automatically generate ready-to-use energy-optimal robot code. Experimental tests, performed on a KUKA Quantec KR210 R2700 prime industrial robot, have confirmed the effectiveness of the method and engineering tool.
Abstract: Robotic deburring (RD) still requires long and delicate physical tests to tune the process-parameters, thus drastically reducing the robotic cell productivity. Henceforth, engineering methods and tools are needed to optimise the RD application within a virtual environment, replicating the real behaviour of the robot tooling under different process conditions, namely unpredictable variety of burr size/shape and limited accuracy of the robot motions. To this purpose, the spindle compliance, which plays a fundamental role, is unfortunately not evaluated by state-of-the-art simulation tools. The present paper proposes a virtual prototype (VP) of a radially-compliant spindle, suitable to assess and optimise the deburring efficiency in different case scenarios. A multi-body model of the spindle, integrated with the process behavioural model, predicts process forces and optimal deburring parameters, delivering the contour maps of the envisaged deburring error as function of feed rate and tool compliance. An industrial case-study is provided.
Abstract: Interventions of ancient bronze statues restoration may last long periods, involving several activities from material and structural analysis to set-up of museum exhibitions, passing through reconstruction of fragments. In this paper, we describe procedures and methods used for evaluation of the current posture of “Principe Ellenistico”. In fact, the statue seems to present some inaccuracies, in the fragments assembly, made during the last restoration activity (one of this effect is clearly observed in the spear inclination). The final aims are: (1) evaluation of differences among the postures before and after the last restoration; (2) recognition of the original fragments embedded in a previous restoration; and (3) the study of a possible better positioning of them. Methods applied are related to feature recognition on acquired point clouds, image analysis through control points and algorithms to find centerline of the elements that could need to be repositioned. In the final part, a concept design for a new inner-support is presented, giving the possibility to avoid assembly inaccuracies. Future developments are presented as the prospect of additive manufacturing the support, firstly with a FDM prototype and then through SLM or similar technologies.
Abstract: Virtual, Augmented and Mixed Reality technologies are more and more getting attention from tourism researchers and professionals, because of their recognized potential to support marketing activities. The paper describes the development of a multisensory environment thought for a travel agency, which combines visual, auditory, tactile and olfactory stimuli. The idea is to develop an experience able to provide a virtual preview of the desired holiday destination, resulting in both an attractive experience for the customer and an effective way to increase sales. A case study about the multisensory experience of a walk on Italian Alps has been developed. The multisensory experience is based on a video streaming, recorded in the real environment, synchronously matched with a haptic interface. The haptic interface is made up of a pair of slippers provided with actuators, and also an actuator positioned on the customer trunk, used to reproduce the feeling of a snowball hit. Moreover, an olfactory display is also used to provide pine smell during the walk. During the experience, the user is sitting on a yoga ball, whose inclination allows him/her to start and stop the multisensory virtual experience.
Abstract: This paper describes the application of a novel virtual prototyping methodology to wind turbine blade design. Numeric modelling data and experimental data about turbine blade geometry and structural/dynamical behaviour are combined to obtain an affordable digital twin model useful in reducing the undesirable uncertainties during the entire turbine lifecycle. Moreover, this model can be used to track and predict blade structural changes, due for example to structural damage, and to assess its remaining life. A new interactive and recursive process is proposed. It includes CAD geometry generation and finite element analyses, combined with experimental data gathered from the structural testing of a new generation wind turbine blade. The goal of the research is to show how the unique features of a complex wind turbine blade are considered in the virtual model updating process, fully exploiting the computational capabilities available to the designer in modern engineering. A composite Sandia National Laboratories Blade System Design Study (BSDS) turbine blade is used to exemplify the proposed process. Static, modal and fatigue experimental testing are conducted at Clarkson University Blade Test Facility. A digital model was created and updated to conform to all the information available from experimental testing. When an updated virtual digital model is available the performance of the blade during operation can be assessed with higher confidence.
Keywords: Composite materials | Design | Digital twin | Finite element method | Modelling and simulation | Wind turbine
Abstract: Molding is one of the most widely used processing technologies in manufacturing. Among typical molding parameters, the mold temperature is a critical one for the quality of the molding process. A solution to this issue can be the employment of induction heating which, through a high-frequency electromagnetic field, produces eddy currents and a consequent rapid heating of the material into the cavity of the mold. The necessity to maintain the mold walls at the operative temperature makes the induction heating to be one of the most efficient non-contact means of heating. In fact, induction heating is characterized by quickness, efficiency, and energy saving; however, the design and the sizing of an induction heating system is complex due to different parameters involved in the electromagnetic and thermal phenomena. In this context, the paper aims to define a methodology to support engineers in the design and sizing of an induction heating system for molds, taking as case study a mold for composite parts. A model-based approach is proposed to analyze and simulate the mold heating, considering three different levels of modelling: Analytical (0D), Finite-Difference Methods (2D) and Finite Element Methods (3D). The Analytical approach investigates the solution of the physical equations applied to the volume of the material involved. Instead, the Finite-Difference approach (2D) solves the heat transfer problem by discretizing the domain and by solving for temperature at discrete points. Finally, the Finite Element method (3D) solves partial differential equations on a 3D discretized domain.
Abstract: The final subject position is often the only evidence in the case of the fall of a human being from a given height. Foreseeing the body trajectory and the respective driving force may not be trivial due to the possibility of rotations and to an unknown initial position and momentum of the subject. This article illustrates how multibody models can be used for this aim, with specific reference to an actual case, where a worker fell into a stair well, prior to stair mounting, and he was found in an unexpected posture. The aim of the analysis was establishing if this worker was dead in that same place, if he had been pushed, and which was his initial position. A multibody model of the subject has been built (“numerical android”), given his stature and his known mass. Multiple simulations have been performed, following a design of experiments where various initial positions and velocity as well as pushing forces have been considered, while the objective function to be minimized was the deviation of the numerical android position from the actual worker position. At the end of the analysis, it was possible to point how a very limited set of conditions, all including the application of an external pushing force (or initial speed), could produce the given final posture with an error on the distance function equal to 0.39 m. The full analysis gives a demonstration of the potentiality of multibody models as a tool for the analysis of falls in forensic inquiries.
Keywords: accident | android | biomechanics | crime | doe | fall | forensic | multibody
Abstract: This work is focused on the analysis of the fall of a human being from a given height. With reference to forensic disputes, the final subject position is often the only evidence and foreseeing the body trajectory and the respective driving force may not be trivial. This article illustrates how multibody models can be used for this aim. A multibody model of a human subject has been built, given his stature and his known mass. This model was made of 15 segments, whose inertial properties, joint centres and volumes were deduced from anthropometric databases. This model was validated against experimental tests performed on a Hybrid III dummy: it was able to reproduce the peak impact head force with an error lower than about 10%. Some examples are produced to illustrate the usefulness of this validated model as a tool for the analysis of falls, and how it can be easily parametrized to make multiple simulations with different initial conditions/environment configurations. As such it is a valuable tool for forensic analyses.
Keywords: Anthropometric data | Fall from height | Forensic biomechancis | Multibody model
Abstract: Increasing the level of automation in air traffic management is seen as a measure to increase the performance of the service to satisfy the predicted future demand. This is expected to result in new roles for the human operator: he will mainly monitor highly automated systems and seldom intervene. Therefore, air traffic controllers (ATCos) would often work in a supervisory or control mode rather than in a direct operating mode. However, it has been demonstrated how human operators in such a role are affected by human performance issues, known as Out-Of-The-Loop (OOTL) phenomenon, consisting in lack of attention, loss of situational awareness and de-skilling. A countermeasure to this phenomenon has been identified in the adaptive automation (AA), i.e., a system able to allocate the operative tasks to the machine or to the operator depending on their needs. In this context, psychophysiological measures have been highlighted as powerful tool to provide a reliable, unobtrusive and real-time assessment of the ATCo’s mental state to be used as control logic for AA-based systems. In this paper, it is presented the so-called “Vigilance and Attention Controller”, a system based on electroencephalography (EEG) and eye-tracking (ET) techniques, aimed to assess in real time the vigilance level of an ATCo dealing with a highly automated human–machine interface and to use this measure to adapt the level of automation of the interface itself. The system has been tested on 14 professional ATCos performing two highly realistic scenarios, one with the system disabled and one with the system enabled. The results confirmed that (i) long high automated tasks induce vigilance decreasing and OOTL-related phenomena; (ii) EEG measures are sensitive to these kinds of mental impairments; and (iii) AA was able to counteract this negative effect by keeping the ATCo more involved within the operative task. The results were confirmed by EEG and ET measures as well as by performance and subjective ones, providing a clear example of potential applications and related benefits of AA.
Abstract: Product customization aims to consider individual customers preferences in the design of new products, in order to directly involve them in the product development process and to maximize their satisfaction. It can be considered a key competitive factor and a "hot topic" in several industrial sectors, including luxury apparel goods and high-end footwear products. However, currently the design and manufacturing of customized shoes are carried out through artisanal and non-standardized processes, based on the individual expertise of operators. The objective of this study is to define an innovative framework to support the different processes affected by customization. This framework is enabled by different digital technologies, as CAD-based tools, virtual/augmented reality systems, etc., opportunely integrated in the product development process. The main benefits related to the framework implementation in real industrial contexts are an increase of flexibility, the repeatability of processes, a higher efficiency in information exchange, a more effective involvement of final customers, and, as a consequence, the reduction of time to market and production costs for tailor-made shoes.
Keywords: Design for X (DfX) | Design process | Integrated product development
Abstract: Nowadays, design processes demand agile and flexible tools and methods to meet market needs. Virtual prototyping techniques are widespread in design strategies and practices, because these technologies reduce the project development lead-time and cost related to physical prototyping. The aim of this paper is the study and application of an approach for the modeling, simulation and geometrical optimization of fans for gas turbine air supply. Fan is a type of machine used to move a fluid, typically a gas such as air, exploiting the kinetic energy of a rotating impeller. It consists mainly of two components: housing and rotor. There is extensive literature on the design and optimization of industrial fan, but main works refer to a small or medium standardized fan, where it is possible to study many parameters and perform many experimental tests. The paper presents an approach for the efficiency optimization of large and customizable centrifugal industrial blowers for gas turbine air supply. The design variables investigated in this study were the blades quantity, orientation and shape. The proposed optimization method has been used for the design optimization of a blower for gas turbine power plant. The response surfaces allowed defining correlation between design variables and efficiency. The optimized design was 18 % more efficient than the original one.
Abstract: Recently, human-centered design has become one of the most promising approaches for improving the entire production process design. During the design phase, among the main important aspects to investigate, ergonomic performance of the workplace (WP) plays a key role. It is well known that design errors can lead to significant delays in the design and engineering of a production process, especially when it is related to a complex system such as the assembly line of an automotive industry. Prediction of the ergonomic performance, which is often coarsely considered during the design phase, can represent a fundamental step in preventing ergonomic issues since the early design phase of a production process, avoiding also negative consequences on line balancing. Based on a concurrent engineering (CE) approach, the aim of this paper is to present a framework that uses digital twins of stations in order to minimise the time necessary to develop and design a new assembly line. The application of this procedure will allow avoiding the possibility of realising a line that reveals ergonomic problems and correcting design errors during the design phase and not just during the production phase. In this way, it is possible to achieve great advantages in terms of cost avoidance for the correction of the design errors and in terms of time to market, which will be significantly reduced. A digital twin of a real station of a Fiat Chrysler Automobiles (FCA) assembly line is presented to validate the numerical procedure and the design approach proposed in this paper. Finally, numerical results, regarding the evaluation of an ergonomic index, were compared with experimental ones achieved by analysing data collected during an experimental session.
Abstract: Automation plays a key role in the realisation of the Factory 4.0 and technological research, combined with the use of innovative materials, contributes to the improvement of products in terms of functional, technical and production quality. Within this context, the so-called Digital Twin allows to reproduce the real behaviour of a production system in a virtual environment, giving the possibility to numerically perform the desired analysis. Human-robot interaction (HRI) is increasing in those workplaces where the manual activity is not safe nor efficient in terms of performance (e.g. cycle time) and it is characterised by several levels of interaction (cooperation, collaboration and coexistence). The aim of this paper is to propose a numerical procedure that, based on the simulation, allows verifying the process feasibility, validating the interaction between human and robot and programming the logic controller to be implemented on the real robot. A case study about assembling of composite components of an aircraft fuselage panel is proposed. The use of the robot allows to speed up the processes of drilling and sealing, leaving to human less dangerous operations.
Keywords: Composite Assembly | Digital Twin | Robot | Simulation
Abstract: Marine archaeologists study a large number of submerged sites of interest around the world, which require continue diving explorations and monitoring. Although technology has improved a lot the research in the underwater environment, human intervention is preferred whenever depth makes the sites accessible by divers. This paper presents the concept, the first steps and the preliminary results of the Lab4Dive project, which is co-funded by the EMFF programme of EU, that aims to design, develop, and validate an innovative, marketable and competitive product for surveying, documenting and preserving Underwater Cultural Heritage. The archaeologist will be provided with an underwater tablet equipped with environmental sensors, where a properly designed data gathering system will be accessible through a dedicated application. Lab4Dive aims also to train young researchers and to encourage multi-disciplinary cooperation through the concept of a “Blue Lab”.
Abstract: The pre-operative planning of a hip arthroplasty entails the choice of the prosthetic hip model and of the position of both joint components with reference to bone. Assessing the impact of geometrical factors on the final hip range of motion (ROM) is not trivial, since it requires performing 3D evaluations. Nonetheless, it deserves to be studied since hip impingement and dislocation are still relevant complications in hip arthroplasty.This work pertains a numerical model for the assessment of the hip ROM in relation to cotyle position. External/internal rotation is considered as a benchmark, and multiple combinations of acetabular anteversion/inclination are considered.According to results, over two hundred different geometric configurations can be examined in few minutes, and the cotyle position can be so optimized with relevant benefits in term of hip ROM.
Abstract: Battery electric vehicles (BEVs) are considered one of the most promising solution to improve the sustainability of the transportation sector aiming at a progressive reduction of the dependence on fossil fuels and the associated local pollutants and CO2 emissions. Presently, the major technological obstacle to a large scale diffusion of BEVs, is the fairly low range, typically less than 300 km, as compared to classical gasoline and diesel engines. This limit becomes even more critical if the electric vehicle is operated in severe weather conditions, due to the additional energy consumption required by the cabin heating, ventilating, and air-conditioning (HVAC). The adoption of vapor-compression cycle, either in heat pump or refrigerator configuration, represents the state-of-the-art technology for HVAC systems in vehicles. Such devices typically employ an expansion valve to abruptly reduce the pressure causing the flash evaporation of the working fluid. This component, although necessary to provide the cooling effect, is also responsible of a significant exergy loss, which reduces the efficiency of the thermodynamic cycle. In this paper we study the possible benefits in terms of energy saving and consequent increase of the driving range, that can be obtained in electric vehicles that adopt a high efficiency HVAC system, where the Tesla turbine replaces the classical expansion valve in order to recover part of the exergy typically lost by the working fluid in the expansion phase. First, an off-design thermodynamic model was developed to assess the performance of the proposed HVAC system as function of the ambient temperature. Then, the calculated COP curves were implemented in an in-house Matlab code based on Nissan Leaf design data. Simulations are carried out considering various reference driving cycles showing that this solution may result in a potential increase of the electric vehicle range up to 5%.
Abstract: Effective identification of the optimal design in the early stages of product development is critical in order to obtain the best chances of eventual customer satisfaction. Currently, the advancements in prototyping techniques offer unique chances to evaluate the features of different design candidates by means of product experts acting as assessors and/or customers enrolled as testers. In this paper, the candidate identification using virtual and physical prototypes is described and a practical fuzzy approach toward the evaluation of the optimal design is presented. The proposed methodology is tested on a full case study, namely the choice of optimal design for the traditional Neapolitan coffeemaker, inspired by the prototypes of the Italian designer Riccardo Dalisi. Several concepts are developed in a virtual environment and four alternatives among them are realized using Additive Manufacturing. By allowing experts to interact with virtual and physical prototypes, they were able to express their opinion on a custom fuzzy evaluation scale (i.e. they were freely choosing more or less coarse linguistic scales as well as the related shapes of fuzzy sets to adequately represent the level of fuzziness of their judgments). Once the opinions are collected, the set of best candidate(s) is easily identified and useful suggestion can be obtained for further developing the product.
Abstract: Despite the widespread use of reverse total shoulder arthroplasty, the fundamental effects of implant configuration on certain biomechanical outcomes have not been completely elucidated especially for the most innovative prostheses. Aim of this work is to investigate the behaviour of a new reverse shoulder prosthesis, characterized by a humeral tray with a variable offset, designed to increase the range of motion and to reduce the impingement. The purposes of this study were to evaluate the effect of reverse shoulder implant design parameters on the deltoid muscle forces, required to produce abduction, and on the shoulder range of motion, in order to provide a more systematic understanding of the fundamental effects of humeral component positioning on the implant performances. The study has been implemented using virtual prototypes of the shoulder-prosthesis assembly. The shape of the prosthesis has been digitally acquired via a 3D scanner and the CAD models of all the components have been created. Through CT images, 3-dimensional models of the shoulder bones have been reconstructed and assembled with the prosthesis components. Numerical FEM models have been set up in order to evaluate how the abduction force changes depending on the humeral tray offset. Using the virtual prototypes of the shoulder-prosthesis assembly, a range of motion analysis has been carried out by setting up a collision detection analysis in a 3D parametric modeling environment. Different humeral tray positions were investigated and four different motions of the arm were simulated. Obtained results have demonstrated that a suitable positioning of the humeral tray can offer significant biomechanical advantages in terms of range of motion and abduction force.
Abstract: Both physical and virtual prototyping are core elements of the design and engineering process. In this paper, we present an industrial case-study in conjunction with a collaborative agile design engineering process and "methodology." Four groups of heterogeneous Post-doc and Ph.D. students from various domains were assembled and instructed to fulfill a multi-disciplinary design task based on a real-world industry use-case. We present findings, evaluation, and results of this study.
Abstract: Chronicles of sieges to castles or fortresses, using "machinae", can often be found in historical sources. Moreover, archaeological excavations of castles or fortresses has brought to light rocks or projectiles whose carving suggests a military usage. Nevertheless, chronicles and discoveries alone, are seldom enough to propose a faithful reconstruction of these machines. Therefore, the aim of this research is the development of methodologies for reconstructing virtual scenarios of sieges, starting from the scarce information available. In order to achieve it, a procedure for the virtual reconstruction of the siege machine has been set up, focusing on typology and dimensions of the machines, also investigating possible fire positions according to topography. The entire procedure has been developed using the siege of Cervara di Roma's Rocca as a case study. Late medieval chronicles (end of 13th Century) report the siege brought by the papal army in order to restore the jurisdiction on the Cervara's stronghold, following the insurrection of a group of vassals headed by a monk named Pelagio. The discovery, in the area of the Rocca, of a stone that could have been used as a projectile confirms what reported. The proposed methodology is composed of two parts. The first one is connected to the study of the "internal ballistics", to understand the performances and to build virtual models of siege machines. The second part is the study of the "external ballistics", then to the positioning and shooting ability of possible machines, analysing the topography of the area. In this paper, we present the feasibility of this methodology through the preliminary results achieved correlating internal and external ballistics.
Abstract: The Bronze Age crossbar wheel found in the XIX century in Mercurago (Italy) is an amazing example of the technical innovations stimulated by the diffusion of horse draught war chariots in Europe across the third and second millennium b.C. In this paper the tools of modern engineering were used to study the structural issues concerning the wheel and the chariot it should be attached to. In particular, the laser-scanner technology and finite element analysis were used for investigating the dimensional, shape and assembly issues of the wheel, as well as for assessing its structural integrity under operating conditions. The role of the inserted nave, which could be similar to modern bushings, was particularly emphasised, as it is a very innovative solution for that time. The performance of a war chariot equipped by this wheel was studied by means of a vehicle dynamics simulation software, hypothesizing two different chariot structures on the basis of Armenian and Egyptian evidences respectively. The former is probably more similar to the chariot to whom the Mercurago wheel was attached; the latter is technically much more advanced. The results of the analysis allowed obtaining important information about the chariot stability, reliability and structural integrity.
Abstract: Lightweight engineering is a current topic in mechanical industry. The mass reduction is a common design objective to reduce product cost and environmental impacts. Virtual prototyping tools are widely applied to study new lightened solutions and check the compliance with regulations and standards. However, an integrated approach, involving simulations and life-cycle analysis, is necessary to support design optimization and decision-making. The scope of this study concerns the definition of an Ecodesign approach to support the lightweight engineering of cast iron parts through the redesign of the product shape. In particular, this paper deals with the optimization of a ductile cast iron manhole. The test case shows a redesign method which considers structural analysis with environmental impacts. The structural analysis has been evaluated using a finite element method tool. In particular, the simulation results have been compared and validated with physical tests. The environmental analysis is based on the methodology provided by the standardized ISO 14040:2006 and ISO 14044:2006. The proposed LCA study considers the phases of manufacturing and transport related to one ductile iron product. The described manufacturing phase is related to a Chinese foundry which produces roughly 12,000 tons of ductile cast-iron castings. The results show the possibility to achieve about 20% of mass reduction for one casting. Considering such mass decreasing, the related reduction in terms of carbon emission is about 7%. Summarizing, this paper shows a design approach to integrate the structural improvements with the reduction of the environmental impacts related to a lighter weight casting.
Abstract: Nowadays, product configuration and optimization are very important topics in several industrial applications such as the manufacturing of Engineered-to-order (ETO) products, where there is a fierce increase in market competition. The product configuration allows past design solutions to be reused and new product variants to be defined and pre-designed. However, the delivery of new configurations of products requires a technical feasibility analysis before closing the contract of the order with the customer. There is a lack of commercial tools which can support the designer from the early configuration phase to the product optimization with the automatic generation of geometric models and simulations. While traditional software tools can be used for the product configuration, with automation in the CAD modeling, other ones can combine optimization algorithms with numerical simulations. However, the combination of all these design levels requires the development of a dedicated platform tools. The research aims to reduce time and cost related to the early design phase of an oil & gas system, focusing on gas turbine ducts. The paper proposes a methodological approach to integrate the design optimization with the product configuration using Model-Based simulations to verify the technical feasibility and to optimize the product design. As a test case, the early design of a gas turbine chimney is proposed.
Keywords: Model-Based simulation | oil & gas | Product configuration | Product optimization | Virtual prototyping
Abstract: Nowadays, several consumer goods are sold with an energy label which provides energy information about consumption, efficiency, noise, and performance. These labels are regulated by local energy policy and governments. Because of this, customers are becoming increasingly aware about the energy efficiency and consumption of products such as household appliances. In Europe, several household appliances are involved in the European Energy Labelling Directive. Therefore, the manufacturers are paying attention to Ecodesign tools and methods to support the development of eco-innovation and sustainable products. In this context, the paper proposes a design methodology to support the development of efficient cooker hoods using an approach based on a constraints satisfaction problem model. The scope of the proposed research is to reduce the time-to-market of household appliances considering the energy efficiency optimization from the early design phases to the embodiment design. A Case Based Reasoning is also implemented to define a pre-configured model of product before the CSP optimization. The CSP model has been developed as an analytical system, which can predict the energy label achieved by a final prototype of a cooker hood. The interaction of such tools can fill the gap between traditional design methods and eco-innovation approaches, in order to support the designer in the decision-making activity. The test case shows a cooker hoods optimization based on a CSP tool, developed using a programming framework based on Gecode platform.
Keywords: Case-based reasoning | Constraints satisfaction problem | Design optimization | Ecodesign | Energy label | Virtual prototyping
Abstract: Design optimization is a common practice in industry. Different mathematical algorithms have been developing to support the optimization in engineering design. The integration between optimization methods and simulations is an interesting issue in engineering design. A typical optimization workflow can include simulation steps; however, the Virtual Prototyping analysis is more time-consuming than analytical calculations. The study of Constraints Satisfaction Problems is a mathematical topic which can be applied for solving engineering issues in design. The strength of this approach is the velocity on searching the satisfied solutions. This paper proposes a design methodology which considers the use of CSP models and calculation tools to optimize the sizing of columns and beams in the design of a steel structure. The calculation tools regard analytical models and numerical analysis. While the analytical approach regards the computing of cost and weight, the numerical analysis is used to verify and check the engineering performance in terms of deformation and stress state. A customized application, based on MiniZinc platform, has been developed and proposed to solve the CSP model for a test case steel structure. The CSP problem has been limited to the calculation of analytical constraints such as cost and weight. Finally, the resultant set of solutions has been evaluated using numerical solution to complete the optimization analysis.
Abstract: The paper defines a framework called virtual eco-design aiming to support designers and engineers in the development of sustainable energy-related products. Virtual prototyping is used to perform energy consumption tests according with ecodesign and energy label regulations. The goal is to build a knowledge-based repository in which virtual tests are stored and classified to create eco-knowledge. Induction hob has been analysed to verify the applicability of the approach and the integration in a traditional product development process. Results highlight how the proposed methodology increases company eco-knowledge providing a tangible support in the definition of energy-label compliant products.
Abstract: The growing attention on sustainable development themes, in line with an increasing awareness of the exhaustibility of natural resources, has made the traditional linear economic model obsolete. Therefore, the concept of "Circular Economy" was developed to favour products and materials recovery and regeneration. To this end Industrial Symbiosis represents a promising approach to foster the transformation towards this type of economy, based on resource efficiency, sustainable manufacturing, materials, energy, water and/or by-products exchange and sharing between different companies. In this context, the aim of this paper is to present a classification and a critical discussion about existing industrial symbiosis models. According to the presented literature review, industrial symbiosis can be realized thorough the implementation of three different models: (i) industrial symbiosis districts that develop from a bottom-up approach and are based on resources sharing and materials exchanging, (ii) eco-industrial parks that develop from a top down approach and are determined by eco-sustainable infrastructures and systems, and (iii) networks for industrial symbiosis that evolve through cognitive/relational tools and are based on resources supply and demand intersection. The final objective of this study is to evaluate strengths and weaknesses of each model, to explore the applicability in real contexts, and to identify potential economic and environmental benefits (e.g. reduction of polluting emissions and landfilled wastes, economic savings due to reuse of scraps, energy sharing). The study concludes by identifying research gaps, reflecting on possible application of industrial symbiosis and proposing suggestions for future work.
Abstract: In the present work a novel rear suspension for motorcycles, able to achieve the required progressiveness in terms of rigidity by using a constant-stiffness spring and an innovative compact mechanism, is studied. The key component is an eccentric system inserted in the shock absorber head. As reference, the rear suspension of the Ducati Multistrada MY 2010, characterized by the use of a variable-stiffness spring, is analyzed. The aim of the paper is to prove that the novel proposed solution can obtain a response, in terms of wheel load, similar to that of the reference system. At first, a mathematical model to simulate the kinematics of the novel suspension is presented. This model is able to evaluate the influence of geometric dimensions of the components, checking successfully the ability to reproduce the behavior of the original suspension. After the preliminary design, the kinetostatic model is included within an optimization algorithm ad-hoc created to obtain the optimum dimensions of each component. In order to obtain the inertial parameters, two 3D models of both the suspensions are created. Finally, two multibody models of the two suspensions are implemented in Adams environment in order to evaluate their dynamic behaviour. Results confirm the goodness of the novel solution being comparable to the reference one in terms of dynamic response during the simulation of a typical experimental test performed in Ducati.
Abstract: The Marchetti-Vicenzi's nail is an intramedullary device where six curved nails are kept straight by a closing ring in order to allow their insertion into the medullary canal of a long bone; in a following step, these nails stabilize the fracture due to the ring withdrawal and to the consequent elastic expansion of the nails. Pre-clinical testing of this sort of device is strongly advocated in order to be able to foresee their stability inside the medullary canal and to quantify their stiffening action on a broken bone. In this numerical work, an MB (Multi Body) model of the device has been developed, with the dual purpose of evaluating forces between the bone and the systemcomponents during its progressive opening and verifying the behavior of the stabilized bone when it undergoes external loading. Different solutions, for flexible body modeling (discretization with lumped parameters, "flexible body," "FE Part"), have been analyzed and compared in terms of accuracy of results and required computational resources. Contact parameters have been identified and criteria to simplify geometries and therefore to reduce simulation times have been given. Results have allowed to demonstrate how amoderate lateral force is able to dislocate the fracture and how the final position of the retention nut can be optimized. On the whole, a tool for the pre-clinical testing of elastic intramedullary nails has been given.
Keywords: FE analysis | Flexible bodies | Intramedullary nails | Marchetti-Vicenzi's nail | Multibody analysis | Sliding contacts
Abstract: In this article, the information value is used in numeric analysis as both a method for data approximation and a measure of data equality among a set of values. To this end, a surface segmentation, based on a study for constructing a hierarchy for vectors clustering using certain similarity criteria, is presented. The technique is based on the analysis of vectors representing regions associated with given types of critical points. An approach based on the Max Entropy in Metric Space (MEMS) is introduced in the paper, in order to extract a cluster of local features and to obtain an analysis of mechanical systems in the 2D and/or 3D spaces. The approach proposed in the paper can be effectively used in virtual prototyping and optimal designing of mechanical systems.
Keywords: Computer Aided Design (CAD) | Max Entropy in Metric Space (MEMS) | Maxinf principle | Multibody Mechanical Systems (MBS) | Optimal design | Virtual prototyping
Abstract: Industrial process plants are increasingly becoming complex structures with high level of automation. Nonetheless, the final plant productivity and the overall equipment efficiency does not solely depend on an optimized engineering design/installation practice, but also on human operators supervision. In parallel, along with the classic demand to minimize costs and time-to-market during the design phases, issues concerning human safety and failure prevention play a crucial role, one of the highest target being the avoidance of dangerous process states. Within this context, Simulation-Based-Training (SBT) allows plant operators to learn how to command complex automated machineries within a secure virtual environment. Similar to its usage in medical, aerospace, naval and military fields, SBT for manufacturing systems can be employed in order to involve the user within a realistic scenario, thus providing an effective, lifelike, interactive training experience under the supervision of experienced personnel. In addition, also according to previous literature, industry-driven SBT may be effectively envisaged as a natural extension of the plant life-cycle simulation practice, comprising Design Simulation & Optimization, Virtual Commissioning, Operator Training, up to Plant Maintenance. In this context, since the overall system behavior depends both on manufacturing process dynamics and Control Logics, the main challenge for an effective SBT is related with the development of a real-time environment where control system responsiveness is fully reproduced. Owing to this consideration, this paper reports a successful industrial case study, concerning a novel SBT workbench used for steel plants operator training, discussing both the virtual prototyping phase and the development of a real-time simulation architecture. In particular, a hybrid process simulation is employed, where a virtual process model is coupled with physical PLC and Human–Machine Interface, thus achieving an accurate reproduction of the real plant/operator interaction.
Keywords: Hybrid virtual/physical simulation | Industrial case study | Simulation-based-training | Virtual commissioning | Virtual prototyping
Abstract: This paper presents a new method for optimizing the layout position of several Industrial Robots (IRs) placed within manufacturing work-cells, in order to execute a set of specified tasks with the minimum energy consumption. At first, a mechatronic model of an anthropomorphous IR is developed, by leveraging on the Modelica/Dymola built-in capabilities. The IR sub-system components (namely mechanical structure, actuators, power electronic and control logics) are modeled with the level of detail strictly necessary for an accurate prediction of the system power consumption, while assuring efficient computational efforts. Secondly, once each IR task is assigned, the optimal work-cell layout is computed by using proper optimization techniques, which numerically retrieve the IR base position corresponding to the minimum energy consumption. As an output to this second development stage, a set of color/contour maps is provided, that depicts both energy demand and time required for the task completion as function of the robot position in the cell to support the designer in the development of an energy-efficient layout. At last, two robotic manufacturing work-cells are set-up within the Delmia Robotics environment, in order to provide a benchmark case study for the evaluation of any energy saving potential. Numerical results confirm possible savings up to 20% with respect to state-of-the-art work-cell design practice.
Abstract: Virtual prototyping enables the validation and optimization of mechanical devices similar to physical testing, saving time and costs in the product development, especially in case of heavy machines with complex motions. However, virtual prototyping is usually deployed only at the end of the design process, when the product architecture has already been developed. The present paper discusses the introduction of virtual prototypes since the conceptual design stage as “Virtual Concepts”, in which coarse models of machinery design variants are simulated to interactively evaluate several solutions and support best design choices. Virtual concept modeling and interactive preliminary validation, along with its later integration into a virtual prototype, are expressly investigated using multi body dynamics software. A verification case study concerning a large vibrating screen is presented, in order to demonstrate that dynamic virtual concepts can enable an easier and effective interactive evaluation of the design variants, thus increasing the design process predictability. Finally, current challenges to be solved for the practical adoption of virtual concept simulations as an integral part of the industrial design process are critically discussed.
Keywords: CAD based simulation | Design process | Vibrating screen | Virtual concepts | Virtual prototyping
Abstract: The actual use of Industrial Robots (IR) for assembly systems requires the exertion of suitable strategies allowing to overcome shortcomings about IR poor precision and repeatability. In this paper, the practical issues that emerge during common “peg-in-hole” assembly procedures are discussed. In particular, the use of passive Remote Center of Compliance (RCC) devices, capable of compensating the IR non-optimal performance in terms of repeatability, is investigated. The focus of the paper is the design and simulation of a flexure-based RCC that allows the prevention of jamming, due to possible positioning inaccuracies during peg insertion. The proposed RCC architecture comprises a set of flexural hinges, whose behavior is simulated via a CAE tool that provides built-in functions for modelling the motion of compliant members. For given friction coefficients of the contact surfaces, these numerical simulations allow to determine the maximum lateral and angular misalignments effectively manageable by the RCC device.
Abstract: According to recent researches, it is desirable to extend Industrial Robots (IR) applicability to strategic fields such as heavy and/or fine deburring of customized parts with complex geometry. In fact, from a conceptual point of view, anthropomorphic manipulators could effectively provide an excellent alternative to dedicated machine tools (lathes, milling machines, etc.), by being both flexible (due to their lay-out) and cost efficient (20-50% cost reduction as compared to traditional CNC machining). Nonetheless, in order to successfully enable highquality Robotic Deburring (RD), it is necessary to overcome the intrinsic robot limitations (e.g. reduced structural stiffness, backlash, time-consuming process planning/optimization) by means of suitable design strategies and additional engineering tools. Within this context, the purpose of this paper is to present recent advances in design methods and software platforms for RD effective exploitation. Focusing on offline methods for robot programming, two novel approaches are described. On one hand, practical design guidelines (devised via a DOE method) for optimal IR positioning within the robotic workcell are presented. Secondly, a virtual prototyping technique for simulating a class of passively compliant spindles is introduced, which allows for the offline tuning of the RD process parameters (e.g. feed rate and tool compliance). Both approaches are applied in the design of a robotic workcell for high-accuracy deburring of aerospace turbine blades.
Abstract: This work describes an integrated method of 3D modelling algorithms with a modal approach in a multibody environment which provides a slimmer and more efficient simulation of flexible component contacts realistically reproducing system impacts and vibrations. A non-linear numerical model of the impulse contact forces based on the continuity approach of Lankarani and Nikravesh is developed. The model developed can evaluate deformation energy taking into account the material's characteristics, surface geometries and the velocity variations of the bodies in contact. ADAMS®-type modelling is applied to the sliding contacts of the links of a chain and its mechanical tensioner (“blade”) in the timing of an internal combustion engine. The blade was discretized by subdividing it into smaller components inter-connected with corresponding centres of gravity through 3D General Forces. Static and dynamic tests were performed to evaluate the stiffness, damping and friction parameters for the multibody model and to validate the methodology.
Abstract: This work analyses the effect of friction in suspension components on a race car vertical dynamics. It is a matter of fact that race cars aim at maximising their performance, focusing the attention mostly on aerodynamics and suspension tuning: suspension vertical and rolling stiffness and damping are parameters to be taken into account for an optimal setup. Furthermore, friction in suspension components must not be ignored. After a test session carried out with a F4 on a Four Poster rig, friction was detected on the front suspension. The real data gathered allow the validation of an analytical model with friction, confirming that its influence is relevant for low frequency values closed to the car pitch natural frequency. Finally, some setup proposals are presented to describe what should be done on actual race cars in order to correct vehicle behaviour when friction occurs.
Keywords: friction | Passive suspension | suspension system | validation
Abstract: The automotive steering system inevitably presents internal friction that affects its response. This is why internal friction phenomena are carefully monitored either by OEMs and by vehicle manufacturers. An algorithm to predict the mechanical efficiency and the internal friction of a steering gear system has been developed by the ZF-TRW Technical Centre of Gardone Val Trompia and the University of Brescia, Italy. It is focused on mechanical steering gear of the rack and pinion type. The main contributions to the overall friction have been identified and modelled. The work is based on theoretical calculation as well as on experimental measurements carried out on a purpose-built test rig. The model takes into account the materials used and the gear mesh characteristics and enables the prediction of the steering gear friction performance before the very first prototypes are built.
Abstract: In Europe, kitchen hoods currently come with an energy label showing their energy efficiency class and other information regarding the energy consumption and noise level, as established by the European Energy Labelling Directive. Because of recent regulations, designs of cooker hoods must consider new issues, such as the evaluation of the energy efficiency, analysis of the energy consumption, and product lifecycle impact. Therefore, the development of eco-driven products requires Ecodesign tools to support eco-innovation and related sustainability improvements. The scope of the proposed research is to define a method and an agile and affordable platform tool that can support designers in the early estimation of product energy performance, including the calculation of energy efficiency indexes. The approach also considers the use of genetic algorithm methods to optimize the product configuration in terms of energy efficiency. The research context concerns large and small productions of kitchen hoods. The paper describes the methodological approach within the developed tool. The results show a good correlation between real efficiency values and calculated ones. A validation activity has been described, and a test case shows how to apply the proposed approach for the design of a new efficient product with an A-class Energy Efficiency Index.
Abstract: During recent years the European Ecodesign Directive has introduced big changes in the design methodology of several energy-using products including consumer goods such as ovens, washing machines and kitchen hoods. Additionally, the introduction of the Energy Labelling Directive pushes manufacturers to implement new energy-saving features in many energy-related products sold in Europe. As a consequence, several companies have been encouraging the improvement of their energy using products paying attention to the related selling cost. Eco-driven products require eco-design tools to support the eco-innovation and the related sustainability improvement. The main scope of the proposed re-search is the reduction of the time-to-market for the energy-using products such as kitchen hoods. In this context, the paper aims to provide an approach to support a pre-evaluation of the energy labeling related to kitchen hoods. A prototypical software tool has been developed in order to simulate the energy performance of new kitchen hood configurations in term of energy efficiency. The approach also considers the introduction of virtual experiments in order to calculate the performance of virtual modules. This tool makes the product-engineer more aware in the decision-making about the energy-saving. As a test case, different product configurations have been compared analyzing the energy labelling and the overall energy performance.
Abstract: The scope of the present research is the reduction of cost and time related to the design, prototyping and testing of a Li-ion battery pack, which is used in commercial full electric vehicles using tools for rapid product configuration and simulation. This objective is particularly important for small companies that produce many different batteries in small lots. To develop the product design support system, a preliminary study was necessary. A 3D model was analyzed to simulate real thermal behavior, reproducing a real electric load using a standard ECE-15 cycle. Experimental tests have been conducted on the vehicle and battery to validate the model. An analytical thermal model was developed to evaluate the heat generated by electrochemical reactions inside a Li-ion cell. The outcome of this analytical model was used as the boundary condition in the CFD simulation of the battery model to evaluate the cooling behavior. The rules and results deduced from these studies have allowed the implementation of an easy-to-use knowledge-based configuration tool that supports the designer in the definition of the layout of the battery pack to save time and evaluate costs. As a test case, the battery for an urban freight vehicle was designed using the proposed approach. The achieved results show good performance and robustness of the simplified approach in terms of temperature distribution evaluation and design process efficiency.
Abstract: Design for Assembly (DfA) is a well-known technique that supports in the reduction of manufacturing costs. Traditional DfA methods are generally focused on the product design lacking of a holistic view. The proposed 4 M approach takes into account all the most important aspects involved in the manual assembly: Method, Machine, Man and Material. The final goal is to provide a means for the concurrent improvement of the product design, the workstation ergonomics, and the assembly tasks. Results obtained with the electric spindle motor case study confirmed the usefulness of the approach in optimizing the manual assembly.
Keywords: 4M approach | Design for assembly | Machine | Man | Material | Method
Abstract: The paper presents a lifecycle approach and the related software tool for the analysis and management of resource consumptions and environmental impacts of manufacturing plants. The approach, based on the industrial metabolism model, takes into account all the production and assembly aspects. The tool is able to assess the optimum working conditions for the minimization of resource consumptions (e.g. electricity) or environmental emissions (e.g. CO2). It provides a tangible support to guide decision-making strategies to move manufacturing towards sustainability. A manufacturing plant has been analysed for the model validation and the management of production scenarios, optimizing environmental and energy loads.
Abstract: During the last 10 years, manufacturing companies have faced new challenges for improving their value proposition and being more efficient and effective on the market, satisfying the customer needs. According to this trend, several technologies have been developed and applied in different sectors and with different aims, in order to support such the companies in their reconfiguration. For example, the recent advances in Information and Communications Technologies (ICT) could give also to manufacturing industries the competences required to develop novel sustainable products embedded with a dedicated infrastructure able to provide more service functionalities to customer. In this context, the application of Internet of Things (IoT) have allowed developing the so named Product Service Systems (PSSs). Moreover, the cross-fertilization between such the technologies with the development of other ones have fostered the application of these novel ICT technologies inside the manufacturing companies also at process level. This approach has encouraged the study and development of Cyber-Physical Systems (CPSs). The present paper deals with a real industrial use case, where the application of ICT technologies and specifically the adoption of IoT at a plant of plastic extrusion pipes have allowed optimizing the production process in terms of energy efficiency.
Keywords: CPS | Cyber Physical System design | ICT | Industry 4.0 | IoT
Abstract: With increased acknowledgment of global climate change and warming, governments, consumers, and firms are responding collectively to create today's low-carbon economy. The eco-design of products is a crucial factor in the Community strategy on Integrated Product Policy. As a preventive approach, designed to optimize the environmental performance of products, while maintaining their functional qualities, it provides genuine new opportunities for manufacturers, consumers and society as a whole. This article presents an approach to support the designers during the energy labeling phases of products. The study starts with an analysis of the Eco-design regulations and proposes the virtualization of such tests. A case study on the application of the proposed method is described. The study results show that, the use of numerical simulations not only for product design but also during the testing and labeling phase, allowing a significant reduction in time to market and provides the company competition and economic, energy, and time savings.
Keywords: Design for enviroment | Design optimization | Eco-design | Energy labelling | Energy-related products | Virtual Prototyping
Abstract: This paper presents a structured User Centered Design (UCD) method to design and develop a highly usable smart home platform to manage the energy consumption of connected appliances. It exploits advanced Tangible Augmented Reality (TAR) technologies to virtually prototype the conceived design solutions and carry out usability testing with sample users. Usability tests are carried out both on traditional high fidelity prototypes and on an innovative Tangible Augmented Reality prototype. Experimental results prove the efficiency of the UCD approach supported by virtual prototypes, instead of traditional ones, the reliability of TAR prototypes to detect usability problems and assess user satisfaction, and its high interaction quality. Advantages obtainable by implementing the proposed structured UCD approach for web interface design, in the context of smart home, are discussed.
Keywords: Human Centered Computing | Human Computer Interaction | User Centered Design | User Interface Design | Virtual Prototyping | Virtual Reality
Abstract: In the present work, by means of an integrated approach, a new rear suspension for motorcycles, able to achieve the required progressiveness in terms of rigidity by using a constant-stiffness spring and a compact mechanism, has been studied. The key component is an eccentric system inserted in the shock absorber head. As reference, we analyzed the rear suspension of the Ducati Multistrada MY 2010, characterized by the use of a variable-stiffness spring. The aim of the paper is to prove that the new proposed solution can obtain a response, in terms of load to the wheel, similar to that of the actual system. At first, a mathematical model to simulate the kinematics of the new suspension is presented. This model is able to evaluate the influence of geometric dimensions of the components, checking successfully the ability to reproduce the behavior of the original suspension. After the preliminary design, the kinematic and static models are included within an optimization algorithm ad-hoc created to calculate the exact dimensions of each component. Two Matlab/Simulink® lumped mass models, respectively referred to the novel and reference suspension, are used to compare the dynamic responses during the travelling of a particular road profile used in Ducati’s experimental tests. Finally, an accurate modeling of the components, considering also the production processes to be used for their creation, is provided.
Abstract: The paper presents a distributed model for implementing Cyber-Physical Systems aimed at controlling physical entities through the Internet of Things. The model tames the inherent complexity of the task by a recursive notion of modularity which makes each module both a controller and a controlled entity. Modules are arranged along part-whole tree-like hierarchies which collectively constitute the system. The behaviour of each module is strictly local since it has visibility only on its controlled modules, but not on the module which controls it. Each behaviour can be thus checked locally at design time against safety and liveness formulas, which still hold when component holons are composed into more complex ones, thus contributing, without the need of additional checks, to the overall safety and liveness of the final system.
Keywords: Cyber-Physical Systems | Holons | Industry 4.0 | Internet of Things | Safety engineering | Smart factories | State-based Control
Abstract: Aim of this paper is to analyse and compare the characteristics of Feature Based and Direct Modeling techniques to determine their pros and cons for typical design processes. The first is one of the most common approach to create CAD models to be used for the machining phase of mechanical parts and assemblies. The second is a new method, alternative to the first one, based on a user-friendly approach, without rigid rules and constraints, that could represent the future of the CAD methodologies. Moreover, the Surface Modeling approach is analyzed and compared to the others, due to its common use in automotive and aeronautics fields. Considering the Feature Based Modeling as benchmark, three case studies were analysed to examine the peculiarities of these techniques, and to determine and highlight their advantages and their drawbacks. Several aspects were contemplated to perform the tests: the execution time for the realization of each operation, the easiness to create features and geometries, the possibility to adequately modify and upgrade the models and the number of operations needed to get the complete virtual prototype. In the end, the results were analysed and discussed focusing the attention on the possibility to adopt the Direct Modeling as substitute of the Feature Based and/or Surface Modeling and of the current CAD techniques.
Keywords: CAD | Direct modeling | Feature based modeling | Fuselage | Main landing fear | Surface modeling | Top-down approach | Virtual prototyping | Wing
Abstract: Position-controlled Servo-Systems (SeSs) may be envisaged as a key technology to keep the manufacturing industry at the leading edge. Unfortunately, based on the current state-of-the-art, these mechatronic devices are well performing but intrinsically energy intensive, thus compromising the overall system sustainability. Therefore, traditional design and optimization paradigms, previously focused on productivity and quality improvement, should be critically reviewed so as to introduce energy efficiency as an optimality criterion alongside with the global production rate. In particular, focusing on mono-actuator systems with one degree-of-freedom, among the several design factors that can influence the SeS overall performance, the end-effector motion law can be easily modified without either hardware substitution or further investments. In this context, the purpose of the present paper is twofold. On one side, an effective method for the quick set-up of an energy-predictive CAD-based virtual prototype is discussed. In parallel, an energy comparison of some commonly employed Point-To-Point motions and optimization cost functions is provided. For what concerns the trajectory interpolation scheme, a standard optimization problem based on the aforementioned virtual model is solved by means of either algebraic or trigonometric splines. For what concerns the optimality criterion, either the system energy consumption or the root-means square value of the actuator torque are taken into account. In general, torque-based approaches, which may be preferred since they do not require a full knowledge of the SeS electrical parameters, can be effectively employed only when friction effects are negligible as compared to purely inertial loads. In parallel, cubic algebraic splines outperform other types of trajectories, although losing continuity of the resulting jerk profile.
Abstract: In this paper, an engineering method for the power flow assessment of a position-controlled servo-mechanism is outlined. The considered system is composed of a permanent magnet synchronous motor coupled to a standard power converter, and directly connected to a slider crank mechanism. After the accurate description of a consistent power flow model, a sequential identification technique is discussed, which allows to determine the dynamic parameters of linkage, electric motor and electronic driver by means of non-invasive experimental measures. The proposed model allows to accurately predict the major sources of power loss within the system.
Keywords: Design of Experiments | Power flow assessment | Servo-actuated mechanism | Virtual prototyping
Abstract: At the current state-of-the-art, Robotic Deburring (RD) has been successfully adopted in many industrial applications, but it still needs improvements in terms offinal quality. In fact, the effectiveness of a RD process is highly influenced by the limited accuracyof the robot motions and by the unpredictable variety of burr size/shape. Tool compliance partially solves the problem, although dedicated engineering design tools are strictly needed, in order to identify those optimized parameters and RD strategies that allow achieving the best quality and cost-effectiveness. In this context, the present paper proposes a CAD-based Virtual Prototype (VP) of a pneumatic compliant spindle, suitable to assess the process efficiency in different case scenarios. The proposed VP is created by integrating a 3D multi-body model of the spindle mechanical structure with the behavioural model of the process forces, as adapted from previous literature. Numerical simulations are provided, concerning the prediction of both cutting forces and surface finishing accuracy.
Abstract: Abstract: The product design process is based on a sequence of phases where the concept of the shape of a product is typically represented through a digital 3D model of the shape, and often also by means of a corresponding physical prototype. The digital model allows designers to perform the visual evaluation of the shape, while the physical model is used to better evaluate the aesthetic characteristics of the product, i.e. its dimension and proportions, by touching and interacting with it. Design and evaluation activities are typical cyclical, repeated as many times as needed in order to reach the optimal and desired shape. This reiteration leads to an increase of the development time and, consequently, of the overall product development cost. The aim of this research work is to develop a novel system for the simultaneous visual and tactile rendering of product shapes, thus allowing designers to both touch and see new product shapes already during the product conceptual development phase. The proposed system for visual and tactile shape rendering consists in a Tactile Display able to represent in the real environment the shape of a product, which can be explored naturally through free hand interaction. The device is designed in order to be portable, low cost, modular and high performing in terms of types of shapes that can be represented. The developed Tactile Display can be effectively used if integrated with an Augmented Reality system, which allows the rendering of the visual shape on top of the tactile haptic strip. This allows a simultaneous representation of visual and tactile properties of a shape. By using the Tactile Display in the initial conceptual phases of product design, the designers will be able to change the shape of a product according to the tactile evaluation, before the development of the physical prototype. This feature will lead to a decrease of the number of physical prototypes needed, thereby reducing, both cost and overall time of the product development process.
Abstract: A methodology for integrating the CAD-CAE design of a chain drive system is presented by evaluating meshing angles. The methodology correlates the angles of engagement with transverse vibrations and the tensile force of the chain links, showing that the dynamic behaviour of a chain drive can be significantly improved by fine tuning the meshing angles. An objective parameter was introduced to evaluate divergence from correct meshing. Here the methodology is applied to optimize the timing chain system of a high power V12 quadruple overhead camshaft engine. The reliability of the method relies on multibody modelling all the components and accurate experimental tests. Correlating the experimental measurements provided exact modelling of the contact forces, exact evaluation of stiffness and damping values and precise dynamic modelling of the tensioners and guides. Finally, the dynamic performance of the two different primary stage chain drive layouts were compared.
Keywords: Chain stiffness | Contact force model | Meshing impact | Multibody dynamics | Tensioner | Transverse vibration
Abstract: The paper presents a lifecycle approach applied to the whole factory plant to characterize primary resource consumptions and environmental impacts for the different processes. The method is based on specific environmental models, defined for each process of a manufacturing plant. The goal is to provide a tangible support to guide decision-making strategies in order to move manufacturing towards sustainability. A case study of a washing machine factory plant has been analyzed to highlight the critical working areas in terms of environmental and energy loads and to support the identification of the corrective actions to increase the overall sustainability.
Keywords: Industrial metabolism | Life Cycle Assessment | Plant lifecycle
Abstract: This study presents an approach based on Design of Experiment (DoE) technique for the optimization of an energy recovery ventilator (ERV). This system is one of the efficient ways to enhance the thermo-hygrometric comfort without increase excessively the thermal load in domestic kitchen. However, there is a major concern, which energy recovery cannot trade off ERV's fan power consumption. The goal of this study is to obtain the information about the relation between factors and response in an empirical way. This approach integrates three different levels of analysis: the virtual prototyping, Design of Experiment (DoE) and rapid prototyping. The virtual analysis allows to define the principal parameterization of a simplified model and to simulate the performance of each configuration at working condition. The proposed approach investigates the effect of the defined parameters and noise factor on the experimental results. In particular, the applied method for DoE analysis is based on virtual experiments in according to the necessity to reduce time and costs during the early design phase. The optimum parameters configuration, which is defined by the previous step, is useful to define the geometry and the working condition of a reliable virtual model. The final level is the realization of a 3D ERV with a rapid prototyping printer. The obtained component is now evaluable at the test bench to investigate the air flow rate and the electric power consumption.
Keywords: Design of Experiments | Energy Recovery Ventilator | Rapid Prototyping | Virtual Prototyping
Abstract: Numerous companies all around the world are shifting from traditional products to product-service solutions, thanks to the increased 'intelligence' and ' connectivity' of modern products and the more deep integration among mechanics, electronics, Information and Commutation Technologies (ICT) and Internet of Things (IoT). Such Product-Service Systems (PSSs) are usually designed and developed by considering product and service as separated entities with the consequent increase of design and validation difficulties. In addition, a final physical prototype has to be realized to validate the overall solution. In this context, Virtual Prototyping can support PSS design to reduce process iterations and time to market. However, actual virtual prototypes are usually conceived for product validation, and are not so effective for PSS. The paper defines a set of requirements for PSS simulation on digital models, and defines a set of tools for successful PSS prototyping.
Abstract: This paper quantitatively reports about a practical method to improve both position accuracy and energy efficiency of Servo-Actuated Mechanisms (SAMs) for automated machinery. The method, which is readily applicable on existing systems, is based on the 'smart programming' of the actuator trajectory, which is optimized in order to lower the electric energy consumption, whenever possible, and to improve position accuracy along those portions of the motion law which are process relevant. Both energy demand and tracking precision are computed by means of a virtual prototype of the system. The optimization problem is tackled via a traditional Sequential-Quadratic-Programming algorithm, that varies the position of a series of virtual points subsequently interpolated by means of cubic splines. The optimal trajectory is then implemented on a physical prototype for validation purposes. Experimental data confirm the practical viability of the proposed methodology.
Keywords: Energy Efficiency | Position Accuracy | Trajectory Optimization | Virtual Prototyping
Abstract: Programmable servo-actuated mechanisms can enhance the flexibility and the reconfigurability of modern manufacturing systems. Differently from fully mechanical design solutions (such as mechanical cams) and especially in the case of high-dynamic motions, servomechanism performance depends on several interacting factors, namely electric motor and linkage dynamics, controller efficacy, and requested motion law. In particular, point-to-point (PTP) trajectories are usually designed in order to comply with technological constraints, imposed by the required interaction with the handled product, and to maximize some optimality criterion such as, for instance, energy efficiency or limited actuation torques. In this context, the present paper proposes a novel method for designing energy and peak-power optimal PTP motions. A standard optimization problem is solved by means of either cubic or quintic splines. Nonetheless, differently from previous approaches, the optimization cost functions are based on a virtual prototype of the system, which comprises behavioral models of power converter, controller, and electric motor coupled with the mechanical system. Results are then compared with experimental data obtained on a physical prototype. The comparison quantitatively shows that better-behaved PTP trajectories can be designed by including the dynamic contribution of each subsystem component.
Abstract: This paper deals with the design and implementation of a double wishbone front suspension for a vineyard-orchard tractor, developed in conjunction with a major tractor brand. To date, independent front suspensions are only found on commercial tractors over 150 kW. A front suspended axle is recognized as a popular option in improving tractor ride performance on larger vehicles. Despite their narrow track, vineyard-orchard tractors are required to have good lateral stability and stability on slopes (i.e. at least 28° rollover angle) and an extremely tight turning diameter for a 4WD vehicle (less than 7 m). The discussion is concered with retrofitting an existing vehicle with a double wishbone front suspension. This paper focuses on the layout and kinematic analysis phases of the design process. These were conducted in collaboration with the vehicle manufacturer to demonstrate suspension feasibility in terms of available space and correct kinematic layout. The final kinematic turning diameter obtained is about 6.4 m, with a ±65 mm suspension travel available. The roll centre height value is not very sensitive to steering (about -95 mm excursion in the Z axis from no-steer position to full steer).
Abstract: The present work describes the interactive prototype and the preliminary evaluation results of a tool dedicated to the light General Aviation pilot’s community. The tool’s interface has been developed through an Android tablet application and aims at supporting the pilots in the task of staying “well-clear” from the surrounding traffic by presenting them the long-term prediction of the flights. The initial results and the approach of a heuristic evaluation conducted with five experts coming from the fields of user-experience, aviation and automotive are discussed along with the improvements in the design of the user-interface focusing on the trajectory depictions.
Abstract: The object of this paper is the development of a decision support system involved in the bidding for invitations to tender in the railway field. The proposed methodology is based on the characterization of the whole train and its components, through several attributes according to a digital pattern approach. In particular some key components were chosen such as the traction motor, the bogie and the auxiliary equipment converter. The system measures the extent to which the products offered by the company fit the one required by the customer, comparing the homologous attributes. Such analysis is called 'adopt/adapt/innovate' (AAI). In this way it is possible to identify products already designed that fully or partly fit what required, obtaining huge benefits in terms of effectiveness and efficiency.
Keywords: Bid | Decision support system | Digital pattern | Digital portfolio | Virtual prototyping
Abstract: In the field of pharmaceutical processing, last generation automatic machines autonomously modify their behavior in order to achieve the best manufacturing quality and productivity despite ever changing process requirements. Mechatronics, as a synergistic integration of electro-mechanical equipment and software control logics, enables such adaptive self-optimizing behaviors. Unfortunately, due to the complex interactions between the different technologies, the final performance of these systems can be effectively validated and optimized only on a physical prototype, with limited possibilities to introduce possible design changes. Therefore, in order to enable validation/optimization of high performance machinery during engineering design stage, a mechatronic Virtual Prototyping (VP) technology is strongly needed. Within this context, the present work discusses a mechatronic VP method based on a Hardware-in-the-Loop, hybrid-process simulation approach, where interactive real-time simulations can effectively assess the real final performance under changing process scenarios. In particular, a case study concerning a high-speed automatic machines for pharmaceutical capsules filling is thoroughly discussed.
Abstract: Dielectric Elastomers (DEs) are deformable dielectrics, which are currently used as active materials in mechatronic transducers, such as actuators, sensors and generators. Nonetheless, at the present state of the art, the industrial exploitation of DE-based devices is still hampered by the irregular electro-mechanical behavior of the employed materials, also due to the unpredictable effects of environmental changes in real world applications. In many cases, DE transducers are still developed via trial-and-error procedures rather than through a well-structured design practice, one reason being the lack of experimental data along with reliable constitutive parameters of many potential DE materials. Therefore, in order to provide the practicing engineer with some essential information, an open-access database for DE materials has been recently created and presented in . Following the same direction, this paper addresses the temperature effect on the visco-hyperelastic behavior of two DE candidates, namely a natural rubber (ZRUNEK A1040) and a well-known acrylic elastomer (3M VHB 4905). Measurements are performed on pure shear specimens placed in a climactic chamber. Experimental stress-strain curves are then provided, which makes it possible to predict hyperelasticity, plasticity, viscosity, and Mullins effect as function of the environmental temperature. Properties of these commercial elastomeric membranes are finally entered in the database and made available to the research community.
Abstract: Nowadays, electric vehicles fill a relevant car market share. The Li-Ion batteries currently represent the best solution in term of environmental impact and performance. Thermal management for Li-Ion batteries is a very interesting topic, since high temperatures accelerate degradation rate of a cell and compromise its safety level. The battery thermal modeling can be quite challenging. The proposed approach describes a methodology to simulate different thermal management algorithms in order to obtain an uniform temperature distribution in a Li-Ion battery pack. A test case has been developed where the application of an thermal algorithm has been analyzed through CFD simulations.
Abstract: Virtual prototyping lacks of application in SME due to the costs of software systems and the necessity of skilled operators. The aim is to improve dripper emitters design process reducing costs. A knowledge base is presented to gather data on products behaviour in terms of experimental data and simulation results for a set of meaningful test cases. Input design parameters were linked to performance indices on the base of the correlations emerged in the analysis. Specifications for a new product can be used to extract similar cases and to define a possible solution in terms of a combination of them.
Keywords: Design of experiments | Drip emitters | Knowledge based engineering | Virtual prototyping
Abstract: Quality of life of various types of people can strongly benefit of a design process developed to take into account needs and requirements of end users. In this context the paper present a study on the cognitive and physical abilities of elderly persons, to design a friendly kitchen, that is considered one of the most complex home environment for the provided functionalities and involved human capabilities. A robust inclusive design approach is conceived to make simple and intuitive the interaction between humans and the systems installed in the kitchen environment. An investigation of virtual prototyping techniques is proposed to find the best Virtual Reality system to create a living lab to involve elderly in user-based assessment.
Abstract: A strong integration between different design tools is desirable to improve the work of engineers, reducing the number of errors and speeding up the design process. In this article, the authors present a strong integration between three-dimensional computer-aided design models and multidomain simulation applied to the design of a magnetomechanical energy harvester. A MATLAB framework controls a block-oriented Simulink model, drives the Finite Element Method Magnetic simulation and manages the updating of the Solid Works computer-aided design models of the device. The parameters involved in the different simulations and in the computer-aided design models are stored in a unique data file. Moreover, constructive drawings are automatically updated and are immediately suitable for tolerance and design constraint checks and also for the effective prototyping of the device. Constructed prototypes are immediately suitable to validate the performance predicted by the model.
Abstract: In the present study, the authors performed a dynamic analysis of the desmodromic timing system, where the valve lifter is realized by conjugate cams, using a methodology of modal synthesis to examine the effects of the deformability of the principal parts, and evaluating the deformations and vibrations of the components under various operating conditions. With this aim, a virtual 3D model and a multibody calculation program were used in a concentrated parameter model, requiring the choice of numerous parameters that greatly affect the results of the analysis. It was therefore important that, within the variability range of these parameters, the values adopted rendered the behavior of the analytical model as close as possible to that of the real system. Finally, the need to evaluate some of the more important aspects of the dynamic system (such as values of clearances, stiffnesses and damping at contacts, and stiffnesses and damping of shafts and belt) made it necessary to validate the model through comparison with experimental trials conducted to determine the valve motion and to measure the strain on the distribution belt.
Abstract: The ability to perform autonomous mission planning is considered one of the key enabling technologies for uninhabited aerial systems. Subsequently, a big effort is made in the development of algorithms capable of computing safe and efficient routes in terms of distance, time, and fuel. In this paper an innovative 3-D planning algorithm is presented. The algorithm is based on considering the uninhabited aerial systems representation of real world systems as objects moving in a virtual environment (terrain, obstacles, and no fly zones), which replicates the airspace. Original obstacle avoidance strategies have been conceived to generate mission plans that are consistent with flight rules and with the vehicle performance constraints. Simulation test results show that efficient routes are computed in a few seconds.
Abstract: The chapter deals with developing small and cheap autonomous underwater vehicles, AUV, entrusted of extended manoeuvrability for surveying and docking missions, requiring accurate path tracking and attitude control, capable of travelling at low speed, down to the proper depth, to accomplish the assigned tasks with reliable autonomy and without relevant impact on the surroundings. The to day available AUVs, generally, make use of several propellers, distributed around the body, to achieve the desired mobility with full attitude control. The solution requires the closure of multiple loops between sensors and actuators, highly cross-coupled and dependent on dynamics non-linearity and marine surroundings disturbances. The prospected solution considers a properly shaped vehicle, to grant minimal drag for lowering power consumption. A single rear propeller has in charge propulsion and manoeuvring. The propeller can be oriented around two axes, say, pitch (for heaving) and yaw (for veering); the screw (hydrodynamic) torque is balanced by variable tilt fins, either, by counter-rotating vanes. A three degrees of freedom parallel-kinematics robotic wrist provides the joint path-and-attitude selection and the twist off-set, by driving the propeller assembly through three independent actuations. The devised submarine wobble-free autonomous navigator, SWAN, is a considerable upgrading of the vectored thrust planning, due to the innovative robotic actuation, permitting the joint heave and veer setting up, with the total balancing of the screw effect around the vehicle axis. The attitude preservation is important figure, each time the AUV's mission requires the accurate angular positioning of the carried instrumentation. The solution makes use of a ductrestricted propeller, with externally driven pitch-and-yaw bending and twist to counter-act the screw torque by continuous rotation, either, by tilted fins. The balancing wile assures local hover or docking, accomplished by active duct counter-rotation, while steady surveying missions exploit the reactive mode, for optimal efficiency. The through-out discussion of the prospected innovative robotic actuation is given, with characterisation of the basic functional and structural features, with account of the on-duty properties and of the conditioning design specification. This way, the noteworthy SWAN's peculiarities emerge, to equip advanced AUVs. The vectored control strategies are also discussed in the chapter. To that purpose, different AUV moving modes (approach to desirable point of space, approach to desirable point of space with desirable orientation, moving on the desirable spatial trajectory, etc.) are taken into consideration. The related examples algorithms, which operate on the heave and the veer setting and on the twist compensation, are investigated, for each navigation mode, also discussing the manoeuvrability abilities of the enhanced vectored propeller actuation, with added autonomy for docking and hovering. The chapter intends to provide full design and development frames of the advanced SWAN solution. The results, obtained by modelling the competing navigation modes, are addressed to document the effectiveness of the innovative robotic actuation, and to show how to work out the duty-oriented solutions, with the resort to the special purpose parallel wrist, in driving the manoeuvring thrust.
Abstract: The main purpose of the present study was to optimize a prototype hexapod robot, called Gregor I, through reverse engineering techniques. The robot is based on experimental observations of the cockroach with regard to mechanical design and the locomotion control strategy. This paper reports on the design phase of a hexapod robot, where the basic geometry of the system is defined through solid modeling and improved through kinematic and dynamic studies, using multi-body software. The dynamic simulation environment made it possible to study the performance of the system under different working conditions. Guidelines for an optimization process of the hexapod structure were drawn from these analyzes, aimed at the improvement of specific characteristics: speed, payload and climbing capabilities. Finally, the robot model and the robot prototype were compared.
Abstract: Although the 3D shape recovery of a real object have been greatly improved in the last few years, modeling a complex virtual object by starting from the real prototype is still a very time-consuming activity. In this paper an originally conceived method and testing software to recover a CAD model from a real object is presented. The developed software tool joins a professional Computer-Aided Design (CAD) and a Mixed Reality (MR) tool in the same interface, enabling the operator to use standard CAD tools and features together with a camera, which provides external image streaming displayed in the workspace background. Moreover, a special programmed library performs a real-time calculation of camera position and other parameters with respect to standard markers in order to drive the CAD 3D virtual camera and align it to external world. In that way rendered virtual models may be superimposed to external images of reality grabbed by the video camera. Thus with MR-CAD tool the operator may easily recover a complex shape directly from the external views of a real object or may start the object re-design from the previous reconstructed geometry. Furthermore the interface is totally integrated in a CAD environment, both avoiding to work with unfamiliar new software and exploiting CAD geometry database and tools. Finally, MR-CAD can be considered a significant step ahead in the bi-directional interaction of virtual and real models, reducing also the gap between real prototypes and CAD data.
Abstract: Researchers in astrophysics and earth observation are still interested in balloon campaigns for making measurements outside the atmosphere. It is possible to trim a bit more from the ballooning costs by increasing the number of parts that can be reused, and by the careful design, the integration and the consolidation of a standard gondola apparatus (something like the mass production of cars). This paper will focus on one of the aspects capable of reducing costs, namely reusable power sources such as solar panels (SP) and fuel cells (FC) and how to protect them during the most difficult phases of the flight (take-off, landing). We will describe two possible ways of deploying and stowing a SP, and report the results of a thermal simulation aimed at ascertaining whether FC may be used in a stratospheric balloon environment.
Abstract: This paper presents a plug-in, named Cloth Assembler, implemented in the framework of the Italian PRIN Project (Research Project of National Interest) VI-CLOTH (Virtual CLOTHing). The base idea is to allow the designer to interactively define/the necessary information to assemble 2D panels on a virtual mannequin and to generate the 3D physical model in its initial configuration, initial step for the garment simulation process. Starting from 2D single pieces, ClothAssembler allows a user, as a virtual tailor, to specify assembly rules among cloth panels (e.g., cut lines, dart, and buttons), insert accessories, such as zips and hooks, and, finally specify finishings on single pieces and the presence of different textile multilayer, pockets, reinforcement lines, etc. The plug-in can be easily integrated with any commercial 2D CAD system and represents the connection element between 2D cloth world and 3D physics-based modelling and simulation systems. It has been validated with three real test-cases, a T-shirt, a denim skirt, and a pair of trousers.
 Bordegoni M., Cugini U.,
Create free-form digital shapes with hands, Proceedings - GRAPHITE 2005 - 3rd International Conference on Computer Graphics and Interactive Techniques in Australasia and Southeast Asia,
Abstract: Gestures, besides speech, represent the mostly used means of expression by humans. For what regards the product design field, designers have multiple ways for communicating their ideas and concepts. One of them concerns the model making activity, where designers make explicit their concepts by using some appropriate tools and specific hand movements on plastic material with the intent of obtaining a shape. Some studies have demonstrated that visual, tactile and kinesthetic feedbacks are equally important in the shape creation and evaluation process . The European project "Touch and Design" (T'nD) (www.kaemart.it/touch-and-design) proposes the implementation of an innovative virtual clay modeling system based on novel haptic interaction modality oriented to industrial designers. In order to develop an intuitive and easy-to-use system, a study of designers' hand modeling activities has been carried out by the project industrial partners supported by cognitive psychologists. The users' manual operators and tools have been translated into corresponding haptic tools and multimodal interaction modalities in the virtual free-form shape modeling system. The paper presents the project research activities and the results achieved so far. Copyright 2005 ACM.
Abstract: In this paper the authors will describe the work which the University of Florence and IFAC-CNR (Florence) have performed in order to design an innovative platform for High-latitude LDB flights based on multi-experiments and versatility concepts. In order to satisfy the functional requirements and difficult structural constraints in terms of stiffness, strength and weight, the authors will describe an innovative approach to designing the gondola using problem-solving techniques, virtual prototyping and topology optimization in a systematic way. By means of these tools, a set of optimized geometries has been tested, starting from the first implementation of the BarSPOrt experiment's platform. Some of these solutions will be described.
Abstract: In addition to stepping through the typical hardware parts of an Attitude Control System borne for stratospheric platform, the paper describes some fast position sensors. The use of two axis magnetometers at high latitude, even though with a lower accuracy, is analyzed. A high-accuracy motorized sun tracker based on a Position Sensitive Detector photodiode capable of driving the gondola in pointing or scanning mode in any given arbitrary anti-sun direction is also presented. Lastly, as an important part of the entire sensor development project, the paper describes a simulation of the thermal behavior of a pressurized cylinder in which electronic photosensitive devices and a CPU system are housed. To employ electronic device built within a commercial temperature range and intended to stay on the ground, it is extremely important to have a pressurized and conditioned environment in order to avoid a reduction in the performances of some ACS components.
Per qualunque informazione non esitare a
contattare la Segreteria ADM tramite le modalità
previste nella sezione Contatti.
Se vuoi diventare membro dell'Associazione ADM, visiona
la pagina "Diventa Socio".
Iscriviti e sarai informato su tutte le
novità riguardanti l'Associazione