
Rega Andrea
Assegnista
Università degli Studi di Napoli Federico II
andrea.rega@unina.it
SCOPUS ID: 57209912700
Orcid: 0000-0002-2819-6119
Pubblicazioni scientifiche
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.
Keywords: Human-robot collaboration | Industry 5.0 | Interactive prototyping | Workplace layout
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: In the paradigm of Industry 4.0, innovative workplaces characterized by Human-Robot Collaboration represent an important topic to improve productivity and adaptability of manufacturing plants. In this context, the design of a collaborative workplace is a challenging issue because of the high level of complexity due to multidisciplinary and non-homogeneity of its features, as well as the presence of human very close to the robot. This work faces with the complexity of collaborative workplace and proposes a structured framework to support strategic decisions in designing. It suggests a clusterization of factors and effects, based on five domains involved in collaborative workplace, in order to better consider the human safety and working conditions. Consequently, the main elements of a collaborative workplace are highlighted in a matrix decomposed in relevant features and main incident factors, and a multi-level designing workflow is described to report collaborative performances. The proposed approach manages connections among the elements by means of the graph theory in the form of an adjacency matrix in order to show and manage the complexity of the problem. A user interface named Smart Graph Interface was developed to read and manipulate the contents of the adjacency matrix. Main results are reported on an assembly and sealing of a refrigerator, to spread out principal outcomes in terms of applicability and robustness.
Keywords: Collaborative workplace design | Graph theory | Human-robot collaboration (HRC) | Multi-level designing | User interface
Abstract: Nowadays, the commercial translation of additive manufacturing technologies for scaffolds fabrication is still a challenge. The production methodology of 3D scaffolds for tissue regeneration is a complex and discontinuous process involving several stages, from the isolation of the stem cells to the dynamic cell culture in vitro. Even though in this scenario industries are increasingly implementing automated robotic systems, current technologies are not enough to realize a large industrial scale scaffold fabrication. Accordingly, a relevant improvement could raise from the implementation of a modern collaborative workplace in an existing production line, combining strength endurance and accuracy of cobots, with intelligence, flexibility, and adaptability of the human being. Such a solution overcomes limits related to the low level of process control, low productivity, and risk of contaminations. Therefore, the current work proposes a systematic approach to the design of a collaborative workplace for biomanufacturing of 3D scaffolds. Starting from an overview of basic concepts on scaffolds for tissue engineering and additive manufacturing, as well as from an analysis of automation solutions in cell culture applications, a design methodology section is reported. The paper provides a further insight into the potentials to upscale the scaffolds manufacturing process, taking advantage of the huge possibilities given from the Human-Robot Collaboration and gives evidence of critical features for workplace definition.
Keywords: Automatic layout generation | Biomanufacturing | Human-Robot Collaboration (HRC) | Workplace design
Abstract: The innovation-driven Industry 5.0 leads us to consider humanity in a prominent position as the center of the manufacturing field even more than Industry 4.0. This pushes us towards the hybridization of manufacturing plants promoting a full collaboration between humans and robots. However, there are currently very few workplaces where effective Human–Robot Collaboration takes place. Layout designing plays a key role in assuring safe and efficient Human–Robot Collaboration. The layout design, especially in the context of collaborative robotics, is a complex problem to face, since it is related to safety, ergonomics, and productivity aspects. In the current work, a Knowledge-Based Approach (KBA) is adopted to face the complexity of the layout design problem. The framework resulting from the KBA allows for developing a modeling paradigm that enables us to define a streamlined approach for the layout design. The proposed approach allows for placing resource within the workplace according to a defined optimization criterion, and also ensures compliance with various standards. This approach is applied to an industrial case study in order to prove its feasibility. A what-if analysis is performed by applying the proposed approach. Changing three control factors (i.e., minimum distance, robot speed, logistic space configuration) on three levels, in a Design of Experiments, 27 layout configurations of the same workplace are generated. Consequently, the inputs that most affect the layout design are identified by means of an Analysis of Variance (ANOVA). The results show that only one layout is eligible to be the best configuration, and only two out of three control factors are very significant for the designing of the HRC workplace layout. Hence, the proposed approach enables the designing of standard compliant and optimized HRC workplace layouts. Therefore, several alternatives of the layout for the same workplace can be easily generated and investigated in a systematic manner.
Keywords: Digital layout optimization | Human–robot collaboration (HRC) | Knowledge-based approach (KBA) | What-if analysis
Abstract: The concept of magnetic guidance has opened a wide range of perspectives in the field of tissue regeneration. Accordingly, the aim of the current research is to design magnetic responsive scaffolds for enhanced bone tissue regeneration. Specifically, magnetic nanocomposite scaffolds are additively manufactured using 3D fibre deposition technique. The mechanical and magnetic properties of the fabricated scaffolds are first assessed. The role of magnetic features on the biological performances is properly analyzed.
Keywords: bone tissue engineering | design for additive manufacturing | magnetic nanocomposite scaffolds | mechanical and functional properties
Abstract: Human–robot collaboration (HRC) solutions are replacing classic industrial robot due to the possibility of realizing more flexible production systems. Collaborative robot systems, named cobot, can work side by side with humans combining their strengths. However, obtaining an efficient HRC is not trivial; indeed, the potential advantages of the collaborative robotics increase as complexity increases. In this context, the main challenge is to design the layout of collaborative workplaces facing the facility layout problem and ensuring the safety of the human being. To move through the high number of safety standards could be very tiring and unproductive. Therefore, in this work a list of key elements, linked to reference norms and production needs, characterizing the collaborative workplace has been identified. Then, a graph-based approach has been used in order to organize and easily manage this information. The management by means graphs has facilitated the implementation of the acquired knowledge in a code, developed in Matlab environment. This code aims to help the designer in the layout organization of human–robot collaborative workplaces in standards compliance. The paper presents the optimization code, named Smart Positioner, and the operation is explained through a workflow diagram.
Keywords: Facility layout problem | Human–robot collaboration | Knowledge-based approach | Optimization criteria
Abstract: The measurement of geometric and dimensional variations in the context of large-sized products is a complex operation. One of the most efficient ways to identify deviations is by comparing the nominal object with a digitalisation of the real object through a reverse engineering process. The accurate digitalisation of large geometric models usually requires multiple acquisitions from different acquiring locations; the acquired point clouds must then be correctly aligned in the 3D digital environment. The identification of the exact scanning location is crucial to correctly realign point clouds and generate an accurate 3D CAD model. To achieve this, an acquisition method based on the use of a handling device is proposed that enhances reverse engineering scanning systems and is able to self-locate. The present paper tackles the device's locating problem by using sensor data fusion based on a Kalman filter. The method was first simulated in a MatLAB environment; a prototype was then designed and developed using low-cost hardware. Tests on the sensor data fusion have shown a locating accuracy better than that of each individual sensor. Despite the low-cost hardware, the results are encouraging and open to future improvements.
Keywords: Handling device | Large-scale metrology | Position measurement | Product design | Sensor data fusion
Abstract: Additive manufacturing represents a powerful tool for the direct fabrication of lightweight and porous structures with tuneable properties. In this study, a fused deposition modelling/3D fibre deposition technique was considered for designing 3D nanocomposite scaffolds with specific architectures and tailored biological, mechanical, and mass transport properties. 3D poly(ε-caprolactone) (PCL)/hydroxyapatite (HA) nanocomposite scaffolds were designed for bone tissue engineering. An optimisation design strategy for the additive manufacturing processes based on extrusion/injection methods was at first extended to the development of the PCL/HA scaffolds. Further insight into the effect of the process parameters on the mechanical properties and morphological features of the nanocomposite scaffolds was provided. The nanocomposite structures were analysed at different levels, and the possibility of designing 3D customised scaffolds for mandibular defect regeneration (i.e., symphysis and ramus) was also reported.
Keywords: Additive manufacturing | Design of Experiments | Nanocomposites | Reverse Engineering | Scaffold Design and Analysis
Abstract: This paper deals with collaborative robotics by highlighting the main issues linked to the interaction between humans and robots. A critical study of the standards in force on human-robot interaction and the current principles on workplace design for human-robot collaboration (HRC) are presented. The paper focuses on an anthropocentric paradigm in which the human becomes the core of the workplace in combination with the robot, and it presents a basis for designing workplaces through two key concepts: (i) the introduction of human and robot spaces as elementary spaces and (ii) the dynamic variations of the elementary spaces in shape, size and position. According to this paradigm, the limitations of a safety-based approach, introduced by the standards, are overcome by positioning the human and the robot inside the workplace and managing their interaction through the elementary spaces. The introduced concepts, in combination with the safety prescriptions, have been organised by means of a multi-level graph for driving the HRC design phase. The collaborative workplace is separated into sublevels. The main elements of a collaborative workplace are identified and their relationships presented by means of digraphs.
Keywords: Anthropocentric approach | Collaborative environment | Digraph | Graph theory | Human-robot collaboration
Abstract: The measurement of geometric deviations within large-size products is a challenging topic. One of the most applied technique compares the nominal product with the digitalization of real product obtained by a reverse engineering process. Digitalization of big geometric models is usually performed by means of multiple acquisitions from different scanning locations. Therefore, digitalization needs to correctly place the acquired point clouds in 3D digital environment. For this purpose, it is very important identifying the exact scanning location in order to correctly realign point clouds and generate an accurate 3D CAD model.The present paper faces the locating problem of a handling device for reverse engineering scanning systems. It proposes a locating method by using sensor data fusion based on Kalman filter, implemented in Matlab environment by using a low-cost equipment.
Keywords: Kalman filter | Position measurement | Product design | Prototypes | Reverse Engineering | Sensor data fusion
Abstract: The present paper deals with collaborative robotics and proposes to enable collaborative workstations by means of the critical study of the in-force standards on Human Robot Cooperation. The paper introduces the anthropocentric paradigm and presents a new basis for designing workstation composed by two key concepts: (i) human and robot spaces are elementary spaces able to generate all other spaces; (ii) dynamic variations of the elementary spaces in terms of shape, size and position occur. Moreover, dynamic positions of human and robot spaces enable collaborative operations in case of mobile robots.
Keywords: anthropocentric design | dynamic workspace | human-robot interaction | safety
Abstract: High accuracy digitalisation of geometric models, related to big size objects, usually is performed by means of multiple acquisitions from different scanning locations. It needs to correctly place the acquired point clouds in 3D digital environment. For this purpose, it is very important identifying the exact scanning location in order to correctly realign point clouds and automatically generate an accurate 3D CAD model. The present paper focuses on design and prototype of a mobile handling device for reverse engineering scanning systems, named Dedalo. It is able to locate itself using a sensor fusion method based on a Kalman Filter. The sensor equipment is composed by wheel encoders and an ultrasonic sensor for measuring the distance from a known reference. Although Dedalo is equipped with low-cost hardware, results have showed a location accuracy by 0,1% error/meter, better than each sensor accuracy.
Keywords: Kalman filter | Position measurement | Product design | Prototypes | Reverse Engineering | Sensor data fusion