[Elenco soci]

Vergnano Alberto

Professore Associato

Università degli Studi di Modena e Reggio Emilia

Sito istituzionale
SCOPUS ID: 26428570500
Orcid: 0000-0003-0999-8869

Pubblicazioni scientifiche

[1] Galati N., Gherardini F., Guaitoli C., Vergnano A., Simulation-Based Design of Reconfigurable Moulds for Injection Overmoulding, Lecture Notes in Mechanical Engineering, 1159-1171, (2023). Abstract

Abstract: The injection moulding process enables the production of complex shaped parts, thanks to the accurate kinematics and the tight tolerances of the mould. This process is suitable for large batch production, leading to reduced single part costs, but involves high initial investments. The life of a mould can be increased by exploiting reconfigurable cavity inserts. So, a design method has been conceived for reconfigurable injection moulds by integrating Design for Assembly and Computer Aided Engineering techniques. From the early phases of a systematic design approach, the simulation models are configured with the different geometries as requested by design specifications. The mould inserts are designed with standard features in order to be quickly changed. A case study on a reconfigurable mould for the overmoulding of polymer wheels to be produced in different sizes is presented. The simulations with Moldex3D software are finally compared with the experimental data from the actual production.

Keywords: Computer Aided Engineering | Design for Assembly | Injection Moulding | Reconfigurable mould

[2] Vergnano A., Salvati E., Magistrelli A., Brambilla E., Veronesi P., Leali F., A method for yield and cycle time improvements in Al alloy casting with enhanced conductivity steel for die construction, Manufacturing Review, 9, (2022). Abstract

Abstract: A die for Al alloy casting must be designed to achieve the expected quality levels. Moreover, the casting unit cost must be regarded as the objective function to be minimised. It can be expressed as a function of the quantity of materials and energy to be used, cycle time and equipment investment. This work compares the performance of the die with inserts manufactured using the usual 1.2343 steel with that of the innovative 1.2383. The latter is considered due to its enhanced thermal conductivity, despite being more expensive. Simulation experiments are designed to evaluate different die layouts. The quality design solutions are evaluated against the cost objective function in order to identify the optimal die choice. A case study on gravity die casting (GDC) of an AlSi7Mg0.3 engine head shows faster solidification dynamics when using 1.2383 instead of 1.2343 steel. This reduces the feeder volume, thus increasing the production yield and speeding up the cycle time with a leverage effect. The higher investment cost for the inserts is rapidly returned thanks to the reduction in variable costs. The Return On Investment (ROI) with the improved die in the new solution is short compared with the life of the die.

Keywords: Cost optimisation | Cycle time | Gravity die casting | Material selection | Process yield | Steel conductivity

[3] Vergnano A., Bergamini U., Bianchi D., Veronesi P., Spagnolo R., Leali F., Simulation and Experimental Validation of Secondary Dendrite Arm Spacing for AlSi7Mg0.3 Chassis Parts in Low Pressure Die Casting, Lecture Notes in Mechanical Engineering, 28-33, (2021). Abstract

Abstract: The structural properties of cast aluminum parts are strongly affected by the solidification in the production process. The solidification dynamics determines the Secondary Dendrite Arm Spacing (SDAS), directly affecting the structural strength of the alloy. Simulation techniques enable the integrated design of chassis parts and their production equipment. However, in order to effectively predict the SDAS formation, the simulation models need to be investigated and calibrated. The present research investigates the SDAS formation models and identifies a robust relation to be used in Design by Simulation phases for AlSi7Mg0.3 parts.

Keywords: Integrated design | Low pressure die casting | Secondary Dendrite Arm Spacing | Simulation

[4] Vergnano A., Piras A., Leali F., Modular Car Seat for Monitoring the Pressure Distribution on Regions of Pan and Backrest, Advances in Intelligent Systems and Computing, 1269 AISC, 9-14, (2021). Abstract

Abstract: Car driver and occupants monitoring is important for safety and comfort. The systems using vision sensors for monitoring the line of sight can be integrated with pressure sensors embedded in the seats to identify critical Out of Position conditions. A new modular car seat is here proposed to monitor the pressure distribution on different significant regions. The solution improves the limitations of existing technologies embedded in seats. The proportional and fast measurement enables online complex evaluations, while the layout reduces the risk of errors. The experiments proved the effectiveness of the prototype.

Keywords: Car seat pressure | Driver monitoring | Driver profiling | Intelligent vehicle | Modular car seat | Occupant classification | Safety system | Seat regions | Weight scale system

[5] Pedrazzi S., Vergnano A., Allesina G., Veronesi P., Leali F., Tartarini P., Muscio A., A simple test method for measurement of the interface thermal resistance of coated and uncoated metal surfaces, Journal of Physics: Conference Series, 1599(1), (2020). Abstract

Abstract: Molds for metal casting are often internally coated in order to minimize the interaction between the steel surface of the mold and the melted metal during its pouring and solidification. However, the added coating increases the thermal interface resistance during the cooling process and it can thus affect the process itself. For example, numerical predictions and experimental results are matched only if the interface resistance is even quintupled in the presence of the usual interface coating, compared to the uncoated mold. In order to have a reasonable estimate of the interface thermal resistance, an easy to use measurement approach has been tested. This consists of contacting a cold and a hot samples of metals with known thermal properties, one at ambient temperature and the other one much hotter. The temperatures of the two samples, assumed to be uniform in each sample, are measured by thermocouples placed inside the samples through a hole, and the interface resistance is calculated from the time evolution pattern of those temperatures during the thermal transient that follows the instant in which the samples have been contacted.

[6] Vergnano A., Gherardini F., Leali F., The systematic design of industrial products through design archetypes: An application on mechanical transmissions, Applied Sciences (Switzerland), 10(7), (2020). Abstract

Abstract: Engineering design is a knowledge intensive activity for both new and mature technical systems, such as mechanical transmissions. However, design knowledge is often transferred with conservative and unstructured approaches, although knowledge management would be of the utmost importance for modern industries. In this work, we introduce a design tool, called design archetype, for collecting and managing knowledge in systematic design processes. The design archetype addresses input design requirements for different design concepts, therefore, improving awareness of the design process by interactively modifying the design solution due to different input requirements. Finally, the design archetype updates the parameters of a first embodiment computer-aided design model of the concept. A method for the development of design archetypes is presented and applied to two case studies of mechanical transmission subassemblies. The results demonstrate the effectiveness of a systematic design method based on design archetypes stored in the company database.

Keywords: CAD-based tool | Design archetype | Knowledge-based engineering | Mechanical transmissions | Systematic design method

[7] Tripi F., Toni R., Calogero A.L., Latessa P.M., Tempesta A., Toselli S., Grigoletto A., Varotti D., Campa F., Manzoni L., Vergnano A., Visual and motor capabilities of future car drivers, Advances in Intelligent Systems and Computing, 1131 AISC, 214-220, (2020). Abstract

Abstract: Driving safety is recognized as critical for young people by institutions, insurances and research. The ability to manage such a complex activity as driving is still developing through adolescence and in early adulthood. The present research investigates the human factors in the driver-car interaction. The experimental method assesses the visual-motor coordination capabilities of future drivers, also in relation to their life styles. The results show that a frequent but good quality physical activity improves visual-motor coordination.

Keywords: Broc String | Distance Rock test | Human factors | Motor Efficiency Test | Peripheral Wall Chart | Visual-Motor coordination

[8] Vergnano A., Gherardini F., Petruccioli A., Bonazzi E., Leali F., Robust Parameter Analysis of Compliant Part Models for Computer Aided Tolerancing, Lecture Notes in Mechanical Engineering, 241-254, (2020). Abstract

Abstract: Sheet metal parts are widely used in automotive, aerospace, ship and consumer goods industries. The final dimensions of a sheet metal assembly result from the parts deformation, which in turn is affected by many variations in material, thickness and single parts dimensions. The tolerance analysis on sheet metal assemblies improve the knowledge about the process. Advanced simulations enable the optimization of product features, GD&T scheme and assembly process. Moreover, Variational Models of both the product and the assembly system enable to assess the sources of 3D error propagation from the different contributors. However, the simulation results are very affected by the modelling approach of critical components, such as the Fixture Systems. The present paper firstly introduces a strategy to model the Fixture System and the assembly process for compliant parts. Then, a robust analysis of the variations in the model with respect to the modelling factors is performed by a Design of Experiments. A case study on an automotive fender is discussed. The results demonstrate that the modelling strategy of the clamping operation have the main effects, while the modelling of locators scheme, spot joints and FEM meshing are less important.

Keywords: 3D tolerances | Compliant parts | Computer Aided Tolerancing | Design method | Robust analysis

[9] Vergnano A., Muscio A., Leali F., Sensor Matrix Robustness for Monitoring the Interface Pressure Between Car Driver and Seat, Advances in Intelligent Systems and Computing, 1026, 229-235, (2020). Abstract

Abstract: An effective sensor system for monitoring the pressure distribution on a car seat would enable researches on Advanced Driver Assistance Systems (ADAS) and comfort of occupants. However, the irregularities of the seat shape or those of the occupant clothes challenge the robustness of such a sensor system. Moreover, the position identification of bodies of different percentiles by few pressure sensors is difficult. So, a higher resolution pressure pad has been developed. The number of sensors is significantly increased by means of a matrix scan strategy. Tests on the pressure pad with different occupants proves its robustness in scanning the contact area.

Keywords: Advanced Driver Assistance Systems | Car seat | Comfort | Driver monitoring | Pressure | Sensor matrix

[10] Vergnano A., Brambilla E., Bonfiglioli G., Efficiency and reliability of gravity die casting models for simulation based design, Lecture Notes in Mechanical Engineering, 3-12, (2019). Abstract

Abstract: Simulation of Gravity Die Casting (GDC) requires coupling different models for fluid dynamics, heat transfer and solidification, together with material physics properties. Very long calculation times are required since several heating and production cycles have to be run. The simplification of the simulation models is critical to have results in times suitable for the design process. The present work discusses the solidification and heat transfer physics with simplification hypotheses. A simulation approach skipping the pouring model for the heating cycles is introduced. A realistic case study on an engine head GDC is presented to evaluate four possible simulation sequences. The results show that including the heating cycles in the simulation is advisable. The simplified sequences reproduce the temperature field of the die with sufficient accuracy. The proposed simulation approach results in considerable time saving with respect to the actual simulations and even in accuracy improvements.

Keywords: Gravity die casting | Model efficiency | Model reliability | Process simulation | Simulation based design

[11] Vergnano A., Pegreffi F., Leali F., Correlation of driver head posture and trapezius muscle activity as comfort assessment of car seat, Advances in Intelligent Systems and Computing, 903, 241-247, (2019). Abstract

Abstract: Car design must very care comfort and driving pleasure. Nonetheless, the design choices are tested with subjective evaluations. In the present research, an objective measurement equipment for driving comfort assessment is proposed. The muscles activity of the driver in different maneuvers is considered the gauge of her/his feeling with the car. The activity of trapezius muscles of both shoulders is monitored by electromyography (EMG), through electrodes applied to her/his skin. The driver posture is monitored with a robust device for head tracking, using two 9-axis orientation sensors, including gyroscope. Real driving experiments are performed both with a luxury SUV and a high-end car. As expected, the first resulted more comfortable. The proposed equipment proved to be effective in assessing the driving comfort for different seat designs and car layouts.

Keywords: Comfort | Driveability | Electromyography | Head tracking

[12] Vergnano A., Leali F., Out of position driver monitoring from seat pressure in dynamic maneuvers, Advances in Intelligent Systems and Computing, 903, 76-81, (2019). Abstract

Abstract: An airbag system is designed to reduce the accident outcome on the car occupants. The airbags deployment against manikins is severely tested according to international regulations. The accident scenarios with Out of Position (OP) occupants are critical since they can be hardly expected during design. The airbag deployment in these scenarios can be improved by developing adaptive strategies, provided that the Airbag Control Unit must be aware of the actual occupant position. The present research investigates a sensor system to monitor the occupants in an interactive Human-Car system. The driver position is monitored by pressure sensors, while an accelerometer enables to compensate for acceleration and noise. Real driving experiments in dynamic conditions are reported. The results prove that three OP conditions are effectively identified.

Keywords: Driver monitoring | Driving experiment | Intelligent vehicle | Out of position | Safety system

[13] Vergnano A., Leali F., Monitoring Driver Posture Through Sensorized Seat, Advances in Intelligent Systems and Computing, 876, 744-749, (2019). Abstract

Abstract: Future intelligent vehicles will be capable to monitor driver distraction while autonomous driving. However, in case of system fault, the intelligent vehicle must also manage an adaptive strategy for the Airbag Control Unit, since the airbag deployment against an Out of Position occupant can be additionally harmful. Thus, the present research work investigates a possibility to monitor the driver position as a robust information to an intelligent vehicle. A seat is sensorized with a map of pressure sensors. The system layout and setup are discussed in details. Signal processing strategy and real driving experiments are reported.

Keywords: Car seat | Driving experiment | Intelligent sensor | Intelligent vehicle | Pressure sensor | Safety system

[14] Vergnano A., Berselli G., Pellicciari M., Interactive simulation-based-training tools for manufacturing systems operators: an industrial case study, International Journal on Interactive Design and Manufacturing, 11(4), 785-797, (2017). Abstract

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

[15] Vergnano A., Berselli G., Pellicciari M., Parametric virtual concepts in the early design of mechanical systems: a case study application, International Journal on Interactive Design and Manufacturing, 11(2), 331-340, (2017). Abstract

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

[16] Peroni M., Vergnano A., Leali F., Brentegani A., Design archetype of gears for knowledge based engineering, Lecture Notes in Mechanical Engineering, 0, 1131-1140, (2017). Abstract

Abstract: An engineering design process consists of a sequence of creative, innovative and routine design tasks. Routine tasks address well-known procedures and add limited value to the technical improvement of a product, even if they may require a lot of work. In order to focus designers work on added value tasks, the present work aims at supporting a routine task with a Design Archetype (DA). A DA captures, stores and reuses the design knowledge with a tool embedded in a CAD software. The DA algorithms drive the designer in selecting the most effective design concept to deliver the project requirements and then embody the concept through configuring a CAD model. Finally, a case study on the definition of a DA tool for gear design demonstrates the effectiveness of the DA tool.

Keywords: Computer Aided Design | Design Archetype | Design automation | Design knowledge | Engineering design

[17] Panari D., Renzi C., Vergnano A., Bonazzi E., Leali F., Integrated design method for optimal tolerance stack evaluation for top class automotive chassis, Lecture Notes in Mechanical Engineering, 2017, (2017). Abstract

Abstract: The tolerances of welded chassis are usually defined and adjusted in very expensive trials and errors on the shop floor. Computer Aided Tolerancing (CAT) tools are capable to optimize the tolerances of given product and process. However, the optimization is limited since the manufacturing process is already mostly defined by the early choices of product design. Therefore, we propose an integrated design method that considers the assembly operations before the detail design of the chassis and the concept design of the fixture system. The method consists in four phases, namely functional analysis in the CAD environment, as-sembly sequence modelling in the CAT tool, Design Of Simulation Experiment on the stack of the tolerance ranges and finally optimization of the tolerances. A case study on a car chassis demonstrates the effectiveness of the method. The method enables to selectively assign tight tolerances only on the main contributors in the stack, while generally requiring cheaper assembly operations. Moreover, a virtual fixture system is the input for the assembly equipment design as on optimized set of specifications, thus potentially reducing the number of trials and errors on the shop floor.

Keywords: 3D tolerancing | Car chassis | Computer aided tolerancing | Design op-timization | Tolerance allocation

[18] Bonazzi E., Colombini E., Panari D., Vergnano A., Leali F., Veronesi P., Numerical Simulation and Experimental Validation of MIG Welding of T-Joints of Thin Aluminum Plates for Top Class Vehicles, Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science, 48(1), 379-388, (2017). Abstract

Abstract: The integration of experiments with numerical simulations can efficiently support a quick evaluation of the welded joint. In this work, the MIG welding operation on aluminum T-joint thin plate has been studied by the integration of both simulation and experiments. The aim of the paper is to enlarge the global database, to promote the use of thin aluminum sheets in automotive body industries and to provide new data. Since the welding of aluminum thin plates is difficult to control due to high speed of the heat source and high heat flows during heating and cooling, a simulation model could be considered an effective design tool to predict the real phenomena. This integrated approach enables new evaluation possibilities on MIG-welded thin aluminum T-joints, as correspondence between the extension of the microstructural zones and the simulation parameters, material hardness, transient 3D temperature distribution on the surface and inside the material, stresses, strains, and deformations. The results of the mechanical simulations are comparable with the experimental measurements along the welding path, especially considering the variability of the process. The results could well predict the welding-induced distortion, which together with local heating during welding must be anticipated and subsequently minimized and counterbalance.

[19] Leali F., Vergnano A., Pini F., Pellicciari M., Berselli G., A workcell calibration method for enhancing accuracy in robot machining of aerospace parts, International Journal of Advanced Manufacturing Technology, 85(1-4), 47-55, (2016). Abstract

Abstract: Industrial robotics provides high flexibility and reconfigurability supported by a user-friendly programming, but still lacks in accuracy. An effective workcell calibration reduces errors in robot manufacturing and enables robot machining applications. A novel workcell calibration method is embedded in an integrated design framework for an in-depth exploitation of CAD-based simulations and offline programming. The method is composed of two steps: first calibration of the workpiece-independent equipment in the workcell layout and final automated online calibration of workpiece-dependent equipment. The method is finally applied to a changeable robotic workcell for finishing aluminium cast housings for aerospace gear transmissions characterised by complex shapes and by close dimensional and geometrical specifications. Experimental results prove the method effectiveness in enhancing accuracy in robot machining.

Keywords: Aerospace industry | Industrial robotics | Integrated design | Workcell calibration

[20] Vergnano A., Renzi C., Leali F., Redesign for environment of wooden packaging for bulk recycling and recovery, ARPN Journal of Engineering and Applied Sciences, 11(1), 528-535, (2016). Abstract

Abstract: Society increasingly demands for effective waste management policies to make industries more environmentally sustainable. Organizations are even issuing directives to drive choices about these policies. In particular, modern industries produce a lot of packaging, which soon become waste, even before product usage. Research can face the problem with improvements in recycling and recovery processes. However, even if recycling and recovery would enable waste to have still a value, most costs and benefits are determined at the design stage. Therefore, Design for Environment criteria must be adopted in the design tasks, from the early conceptual design when the main design solutions are defined. The design criteria to assess possible design choices must consider all the environmental impacts of packaging over its lifecycle. The present work focuses on Redesign for Environment of packaging solutions. Following a systematic design process, we use different criteria to evaluate the effects of design solutions on packaging, since waste can be seen just as one of the main phases of packaging life. To this purpose, we adopt the stages of the waste hierarchy set by the EU Waste Framework Directive 2008/98/EC as design evaluation criteria. The waste hierarchy sets a priority order for five life cycle stages that a packaging can go through. The stages of the hierarchy can be differently weighted according to the costs and benefits they involve. The proposed Design for Environment method based on the waste hierarchy criteria is finally applied in the redesign of an industrial case study. The packaging solution as foldable wooden crates were chosen for their capability to already comply with the first stages of the hierarchy, that is reducing waste with high customization to customer requirements and crate reuse. Hence, the case study improved the next stages with easing the wood recycle and recovery processes.

Keywords: Design for environment | Foldable wooden crates | Packaging | Recovery | Recycling | Waste hierarchy

[21] Pellicciari M., Vergnano A., Berselli G., Hardware-in-the-Loop Mechatronic Virtual Prototyping of a high-speed capsule filling machine, MESA 2014 - 10th IEEE/ASME International Conference on Mechatronic and Embedded Systems and Applications, Conference Proceedings, (2014). Abstract

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.

Keywords: Hardware-in-the-Loop | Intelligent Manufacturing | Mechatronic Design | Virtual Prototyping

[22] Vergnano A., Pellicciari M., Berselli G., Hardware in the loop simulation-based training for automated manufacturing systems operators, FAIM 2014 - Proceedings of the 24th International Conference on Flexible Automation and Intelligent Manufacturing: Capturing Competitive Advantage via Advanced Manufacturing and Enterprise Transformation, 873-880, (2014). Abstract

Abstract: Simulation-Based-Training (SBT) allows to train the operators of complex machinery within a safe virtual environment by means of effective lifelike learning experiences. SBT has been efficiently used in medical, aerospace and military fields and it may provide a competitive advantage also for the training of operators in mechatronic plants. In fact, at the current state of the art, human-machine interaction still heavily impacts on the final performances of automated plants. Since the fast-evolving process dynamics of the machinery is controlled and supervised by complex software logics, the main challenge for effective and valid SBT concerns the development of a real-time simulation, where the control system responsiveness is fully reproduced. This paper deals with a novel SBT workbench used for steel plants operator training, discussing the real-time simulation architecture developed for the purpose. Following a hybrid process simulation approach, real-time control Hardware-In-the-Loop technology assures seamless and accurate reproduction of the real plant, also achieving the desired Man-in-the-Loop practice for the operator interaction. A conceptual architecture for a virtual interactive prototype is proposed, including controllers and interfaces for trainer and trainees. A case study on an electric arc furnace is implemented within a Virtual Commissioning tool, analyzing its capabilities and limitations.

[23] Vergnano A., Marsala M., Costantino A., Balugani F., Efficient simulation of single degree of freedom servomechanisms for automatic machines, Applied Mechanics and Materials, 365-366, 921-925, (2013). Abstract

Abstract: An automatic manufacturing system design must be optimized with a simulation including all the interacting devices. The simulation should be controlled by the real control system with a hardware in the loop approach. So the techniques for modeling the mechanisms must be effective for the model to be run without violating the real-time protocol. This paper reports a method to model the motor load by means of a reduced moment of inertia, where all the part downstream from the motor output shaft is transformed in function of the only one mechanism degree of freedom. The resulting model behaves as the real nonlinear mechanism, but it is computationally efficient since it is not ruled by the multibody 3D CAD mathematics. © (2013) Trans Tech Pudlications, Switzerland.

Keywords: Co-simulation | Digital product design | Virtual prototyping

[24] Leali F., Pellicciari M., Pini F., Vergnano A., Berselli G., A calibration method for the integrated design of finishing robotic workcells in the aerospace industry, Communications in Computer and Information Science, 371, 37-48, (2013). Abstract

Abstract: Industrial robotics provides high flexibility and reconfigurability, cost effectiveness and user friendly programming for many applications but still lacks in accuracy. An effective workcell calibration reduces the errors in robotic manufacturing and contributes to extend the use of industrial robots to perform high quality finishing of complex parts in the aerospace industry. A novel workcell calibration method is embedded in an integrated design framework for an in-depth exploitation of CAD-based simulation and offline programming. The method is composed of two steps: a first offline calibration of the workpiece-independent elements in the workcell layout and a final automated online calibration of workpiece-dependent elements. The method is finally applied to a robotic workcell for finishing aluminum housings of aerospace gear transmissions, characterized by complex and non-repetitive shapes, and by severe dimensional and geometrical accuracy demands. Experimental results demonstrate enhanced performances of the robotic workcell and improved final quality of the housings. © Springer-Verlag Berlin Heidelberg 2013.

Keywords: Aerospace industry | Industrial robotics | Integrated design | Workcell calibration

[25] Leali F., Pellicciari M., Pini F., Berselli G., Vergnano A., An offline programming method for the robotic Deburring of aerospace components, Communications in Computer and Information Science, 371, 1-13, (2013). Abstract

Abstract: Deburring of aerospace components is a complex task in case of large single pieces designed and optimized to deliver many mechanical functions. A constant high quality requires accurate 3D surface contouring operations with engineered tool compliance and cutting power. Moreover, aeronautic cast part production is characterized by small lot sizes with high variability of geometries and defects. Despite robots are conceived to provide the necessary flexibility, reconfigurability and efficiency, most robotic workcells are very limited by too long programming and setup times, especially at changeover. The paper reports a design method dealing with the integrated development of process and production system, and analyzes and compares a CAD-based and a digitizer-based offline programming strategy. The deburring of gear transmission housings for aerospace applications serves as a severe test field. The strategies are compared by the involved costs and times, learning easiness, production downtimes and machining accuracy. The results show how the reconfigurability of the system together with the exploitation of offline programming tools improves the robotic deburring process. © Springer-Verlag Berlin Heidelberg 2013.

Keywords: CAD-based tools | Digitizers | Industrial robotics | Integrated design | Offline programming

[26] Pellicciari M., Berselli G., Leali F., Vergnano A., A method for reducing the energy consumption of pick-and-place industrial robots, Mechatronics, 23(3), 326-334, (2013). Abstract

Abstract: The interest in novel methods and tools for opt imizing the energy consumption in robotic systems is cur- rently increasing. From an industrial point of view,it is desirable to develop energy saving strategies also applicable to established manufacturing systems with no need for either hardware substitu tion or further investme nts. Within this scenario,the present paper reports amethod for reducing the total energy con- sumption of pick-and-place manipulators for given TCP position profiles.Firstly,electromechanical mod- els of both serial and parallel manipulators are derive d.Then,the energy-optimal trajectories are calculated, by means of constant time scaling,starting from pre-scheduled trajectories comp atible with the actuation limits. In this manner,the robot work cycle can be energetically optimized also when the TCP position profiles have been already definedon the basis of technological constraints and/or design choices aimed at guarante eing manufacturing process efficacy/robustness.The effectiveness of the pro- posed procedure is finallyevaluated on two simulation case studies. Copyright © 2013 Published by Elsevier Ltd. All rights reserved.

Keywords: Electromechanical modeling | Energy efficiency | Robotic manufacturing | Virtual prototyping

[27] Wigstrom O., Lennartson B., Vergnano A., Breitholtz C., High-level scheduling of energy optimal trajectories, IEEE Transactions on Automation Science and Engineering, 10(1), 57-64, (2013). Abstract

Abstract: The reduction of energy consumption is today addressed with great effort in manufacturing industry. In this paper, we improve upon a previously presented method for robotic system scheduling. By applying dynamic programming to existing trajectories, we generate new energy optimal trajectories that follow the same path but in a different execution time frame. With this new method, it is possible to solve the optimization problem for a range of execution times for the individual operations, based on one simulation only. The minimum energy trajectories can then be used to derive a globally energy optimal schedule. A case study of a cell comprised of four six-link manipulators is presented, in which energy optimal dynamic time scaling is compared to linear time scaling. The results show that a significant decrease in energy consumption can be achieved for any given cycle time. © 2004-2012 IEEE.

Keywords: Optimization methods | scheduling | trajectory

[28] Meike D., Pellicciari M., Berselli G., Vergnano A., Ribickis L., Increasing the energy efficiency of multi-robot production lines in the automotive industry, IEEE International Conference on Automation Science and Engineering, 700-705, (2012). Abstract

Abstract: This paper quantitatively reports about potential energy savings on robotic assembly lines for the automotive industry. The key aspect of the proposed approach is that both cell production rate and robot hardware limitations are considered as strict constraints, so that no plant revision is needed. The methodology relies on: a) calculation of energy-optimal trajectories, by means of time scaling, concerning the robots' motion from the last process point to the home positions; b) reduction of the energy consumption via earlier release of the actuator brake when the robots are kept stationary. Simulation results are presented, which are based on the production timing characteristics measured on a real plant. © 2012 IEEE.

Keywords: Energy Efficiency | Industrial Robots | Production Planning | Trajectory Scaling

[29] Vergnano A., Thorstensson C., Lennartson B., Falkman P., Pellicciari M., Leali F., Biller S., Modeling and optimization of energy consumption in cooperative multi-robot systems, IEEE Transactions on Automation Science and Engineering, 9(2), 423-428, (2012). Abstract

Abstract: Reduction of energy consumption is important for reaching a sustainable future. This paper presents a novel method for optimizing the energy consumption of robotic manufacturing systems. The method embeds detailed evaluations of robots' energy consumptions into a scheduling model of the overall system. The energy consumption for each operation is modeled and parameterized as function of the operation execution time, and the energy-optimal schedule is derived by solving a mixed-integer nonlinear programming problem. The objective function for the optimization problem is then the total energy consumption for the overall system. A case study of a sample robotic manufacturing system and an experiment on an industrial robot are presented. They show that there exists a real possibility for a significant reduction of the energy consumption in comparison to state-of-the-art scheduling approaches. © 2012 IEEE.

Keywords: Energy optimization | mathematical programming | robot cells | scheduling and coordination | system modeling and simulation

[30] Andrisano A.O., Leali F., Pellicciari M., Pini F., Vergnano A., Hybrid Reconfigurable System design and optimization through virtual prototyping and digital manufacturing tools, International Journal on Interactive Design and Manufacturing, 6(1), 17-27, (2012). Abstract

Abstract: Engineering changeability-oriented and cost-driven approaches are needed by enterprises to design and optimize manufacturing and assembly systems for the demanding production requirements of the present industrial scenario. The integrated design of Reconfigurable Systems addresses tailored flexibility through modularity, integrability of resources, product and process customization, and system convertibility and diagnosability. The cooperation of robot and humans in hybrid environments offers a good trade-off between changeability, high quality and low costs, by exploiting the human dexterity and cognitive proactivity, together with robotic accuracy and performances. Virtual prototyping methods and digital manufacturing solutions are now mature and effective enough to play a strategic role within the hybrid reconfigurable system (H-RS) design and optimization process. The present research work proposes an engineering method to design and optimize H-RSs, by using virtual prototyping and digital manufacturing as a strategic support for the analysis and synthesis of the technical solutions, especially those related to human-robot cooperation. An industrial case study on a hybrid reconfigurable assembly system of a top class car aluminum chassis is finally presented. © 2011 Springer-Verlag.

Keywords: Automotive industry | Digital manufacturing | Hybrid reconfigurable system | Virtual prototyping

[31] Pellicciari M., Berselli G., Leali F., Vergnano A., A minimal touch approach for optimizing energy efficiency in pick-and-place manipulators, IEEE 15th International Conference on Advanced Robotics: New Boundaries for Robotics, ICAR 2011, 100-105, (2011). Abstract

Abstract: The interest in novel engineering methods and tools for optimizing the energy consumption in robotic systems is currently increasing. In particular, from an industry point of view, it is desirable to develop energy saving strategies applicable also to established manufacturing systems, being liable of small possibilities for adjustments. Within this scenario, an engineering method is reported for reducing the total energy consumption of pick-and-place manipulators for given end-effector trajectory. Firstly, an electromechanical model of parallel/serial manipulators is derived. Then, an energy-optimal trajectory is calculated, by means of time scaling, starting from a pre-scheduled trajectory performed at maximum speed (i.e. compatible with actuators limitations). A simulation case study finally shows the effectiveness of the proposed procedure. © 2011 IEEE.

Keywords: energy efficiency | Pick-and-place manipulators

[32] Pellicciari M., Berselli G., Leali F., Vergnano A., Lennartson B., Object-oriented modeling of industrial manipulators with application to energy optimal trajectory scaling, Proceedings of the ASME Design Engineering Technical Conference, 5(PARTS A AND B), 997-1006, (2011). Abstract

Abstract: The development of safe, energy efficient mechatronic systems is currently changing standard paradigms in the design and control of industrial manipulators. In particular, most optimization strategies require the improvement or the substitution of different system components. On the other hand, from an industry point of view, it would be desirable to develop energy saving methods applicable also to established manufacturing systems being liable of small possibilities for adjustments. Within this scenario, an engineering method is reported for optimizing the energy consumption of serial manipulators for a given operation. An object-oriented modeling technique, based on bond graph, is used to derive the robot electromechanical dynamics. The system power flow is then highlighted and parameterized as a function of the total execution times. Finally, a case study is reported show- ing the possibility to reduce the operation energy consumption when allowed by scheduling or manufacturing constraints. Copyright © 2011 by ASME.

[33] Vergnano A., Thorstensson C., Lennartson B., Falkman P., Pellicciari M., Yuan C., Biller S., Leali F., Embedding detailed robot energy optimization into high-level scheduling, 2010 IEEE International Conference on Automation Science and Engineering, CASE 2010, 386-392, (2010). Abstract

Abstract: Reduction of energy consumption is important for reaching a sustainable future. This paper presents a novel method for optimizing the energy consumption of robotic manufacturing systems. The method embeds detailed evaluations of robots' energy consumptions into a scheduling model of the overall system. The energy consumption for each operation is modelled and parameterized as function of the operation execution time, and the energy-optimal schedule is derived by solving a mixed-integer nonlinear programming problem. The objective function for the optimization problem is then the total energy consumption for the overall system. A case study of a sample robotic manufacturing system is presented. It shows that there exists a possibility for a significant reduction of the energy consumption, in comparison to state-of-the-art scheduling approaches. © 2010 IEEE.

[34] Pellicciari M., Andrisano A.O., Leali F., Vergnano A., Engineering method for adaptive manufacturing systems design, International Journal on Interactive Design and Manufacturing, 3(2), 81-91, (2009). Abstract

Abstract: Adaptive manufacturing systems achieve intelligence and adaptation capabilities through the close interaction between mechanics, electronics, control and software engineering. Mechatronic design of intelligent manufacturing behaviours is of paramount importance for the final performances of complex systems and requires deep integration between mechanical and control engineering. Virtual Commissioning environments offer engineers new opportunities for the design of complex intelligent behaviours and for the enhancement of the performance of adaptive manufacturing systems. This paper discloses a systematic design method focused on interdisciplinary behavioural simulations: Virtual Commissioning tools are used to virtually explore new solution spaces for an effective mechatronic optimization. The results, achieved by applying the method in reengineering a module of an automotive sensor manufacturing line, are finally presented. © 2009 Springer-Verlag.

Keywords: Computer aided engineering | Mechatronic design | Virtual commissioning