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Mathematical modeling of hybrid soft robots is complicated by the description of the complex shape that they undergone when subject to actuation and external loads. It might be noticed that several approaches have been used so far in robotics, and the problem is not yet fully solved. This short paper aims at presenting an overview of modeling and simulation approaches for soft robots based on finite element methods. Benefits and perspectives of future directions are also discussed.

Water-cooled lithium-lead breeding blanket is considered a candidate option for European DEMO nuclear fusion reactor. ENEA and the linked third parties have proposed and are developing a multi-module blanket segment concept based on DEMO 2015 specifications. The layout of the module is based on horizontal (i.e. radial-toroidal) water-cooling tubes in the breeding zone, and on lithium lead flowing in radial-poloidal direction. This design choice is driven by the rationale to have a modular design, where a basic geometry is repeated along the poloidal direction. The modules are connected with a back supporting structure, designed to withstand thermal and mechanical loads due to normal operation and selected postulated accidents. Water and lithium lead manifolds are designed and integrated with a consistent primary heat transport system, based on a reliable pressurized water reactor operating experience, and the lithium lead system. Rationale and features of current status of water-cooled lithium-lead breeding blanket design are discussed and supported by thermo-mechanics, thermo-hydraulics and neutronics analyses. Open issues and areas of research and development needs are finally pointed out.

This paper presents a novel instant 3D whole body scanner for healthcare applications. It is based on photogrammetry, a digital technology which allows to reconstruct the surface of objects starting from multiple pictures. The motivation behind this work is the development of minimally invasive procedures for instant data acquisitions of anatomical structure. The scanner provides several features of interests in 3D body scanning technologies for the healthcare domains: (i) instant capture of human body models; (ii) magnitude of accuracy in the order of 1 mm; (iii) simplicity of use; (iv) possibility to scan using different settings; (v) possibility to reconstruct the texture. The system is built upon a modular and distributed architecture. In this paper we highlight its key concepts and the methodology which has led to the current product. We illustrate its potential through one of the most promising 3D scanning healthcare applications: the data acquisition and processing of human body models for the digital manufacturing process of prostheses and orthoses. We validate the overall system in terms of conformity with the the initial requirements.

The current trend in manufacturing is to obtain a flexible work cell in which human and robot can safely interact and collaborate. Virtual Reality (VR) represents an effective tool capable of simulating such complex systems with a high level of immersion. In order to take advantage of VR technologies to study Human-Robot Cooperation (HRC), a digital model of a redundant manipulator (KUKA LBR iiwa) has been developed starting with kinematic modeling and then coupled with the real robot. This approach allows simulating HRC in several scenarios, to reproduce the safe behavior on the real robot, as well as to train operators.

This study aims to develop an innovative approach based on a wearable inertial system, which enables objective evaluations on the of loss of ground contact in race-walking, in order to assist coaching and judging. The architecture of the system, its positioning on the human body and functional requirements were defined through a Kansei Engineering approach by using a significant sample of athletes, coaches and judges within the race-walking environment. The analysis of variance supports decisions concerning the optimal system architecture consisting of an inertial sensor positioned on the centre-of-mass of the subject and a control unit. The selected device was then validated in laboratory conditions by means of an integrated system, including dynamic (680 Hz) and kinematic (340 Hz) devices, which are more accurate than the inertial system (200 Hz). The experiment was carried out at the Fraunhofer JL IDEAS-MISEF at CESMA, Laboratory of Advanced Measures on Ergonomics and Shapes of the University of Naples Federico II where four elite race walkers performed 60 test-runs according to a well-defined experimental protocol. Results proved that the inertial system could improve the accuracy in detecting illegal steps. Through statistical classification, it was found that the proposed approach has achieved encouraging results in comparison with state of the art approaches and could be a good architecture to develop a valuable tool to assist experts. © 2016, Springer-Verlag France.

In this work we present a study for the experimental reconstruction of the human shoulder torque in the sagittal plane, since this is usually overloaded in industrial overhead tasks. To this end, we measure the three-dimensional motion of the human upper limb while performing selected movements using an optical motion capture system. Then, using a skeleton model implemented in one of the most common software for industrial ergonomic assessment, we reconstruct the shoulder angle and torque in the sagittal plane. A possible exploitation of this reconstruction strategy is presented for active compensation of this torque. The implementation of this simple strategy in a custom developed assistive device could augment human workers in performing repetitive jobs. © 2019 IEEE.

The musculoskeletal disorders represent one of the most common problems in industrial environment; they impact the health of workers and employees. In this work we present a preliminary study towards the use of biomechanical models for improving classic methods for ergonomic assessment in industry. To this end, we use OpenSim, a software for biomechanical simulation and analysis. With OpenSim, we reconstruct the human motion corresponding to the execution of industrial tasks, performed in laboratory settings. In particular, we compute the evolution over time of the joint angles that, according to a classic observation method for ergonomic assessment, are needed to evaluate the risks associated to the musculoskeletal disorders for the upper limb. © 2019 IEEE.

This paper investigates the thermal and fluid dynamic effects of a cold air jet generated by a Ranque-Hilsch vortex tube on the cutting tool of a milling machine. A simulation model that predicts the temperature field and the displacements of the tool due to the thermal effects was developed. Such a model can help to correct machining errors and improve cutting accuracy of air-cooled milling machines. Experimental results validated the model. Eventually, the post-processing of the computational fluid dynamics (CFD) data has been conducted in virtual reality.

This work focuses on an innovative training methodology based on the use of Virtual ergonomics and “serious games” in the field of occupational safety. Virtual Ergonomics was chosen as an effective and convincing tool for disseminating the culture of safety among the workers, while a “serious game” was developed to train operators on specific safety procedures and to verify their skills. The results of the experimentation in a real industrial case study showed that, compared to the traditional training methodology, multimedia contents and quantitative ergonomic analyses improve the level of attention and the awareness of the operators about their safety. On the other hand, Serious games turned out as promising tools to train the workers about safe operating procedures that are difficult to implement in a real working environment. © Springer Nature Switzerland AG 2019.

In this paper we present the design, prototyping and validation of a novel adjustable foot stretcher for indoor rowing training. The overall process is user-centered, in the sense that the athletes are directly involved in all the phases of the product development, from conceptual design to evaluation and validation. The conceptual design starts from well-known rowers needs. Accordingly, two design factors are selected to parametrize the prototype, namely the inter-axle spacing feet and the foot angle. The experimental evaluation and validation involve two phases, one based on a quantitative analysis of the performance, one based on subjective questionnaires submitted to the athletes. The performance-based analysis comprises the derivation of three pressure indices and one power transmission index. Indeed, the subjective analysis regards the users comfort and power transmission feelings. The results of both evaluations testify that an improvement in performance and comfort of the indoor rowing training session can be achieved.

The use of Augmented Reality (AR) technologies is the new challenge of management models born under the ""Industry 4.0"" paradigm. The aim of the work is to evaluate the usability of two types of AR devices (tablet and see-through) employed in the training and information activities of workers according to the ISO/IEC 9126 and ISO 9241 standards. Starting from the state of the art, evaluating market and competitors and developing different concepts of interfaces, a dedicated application was programmed and, then, the usability of such devices for the professional figures involved was evaluated through experimental tests. Two reference scenarios were defined, the Department of Industrial Engineering of University of Naples Federico II and INAIL (National Institute for Insurance against Accidents at Work) laboratories, an user interface was designed and developed, as an aid in the drafting of the document for risk evaluation and subsequent training of workers. The activity is part of the IDEE Project (Interactive Design for Ergonomics), born by the collaboration between Joint Lab IDEAS and Contarp-INAIL-Regional Management for Campania. The data analysis allowed to evaluate the goodness of the devices and the degree of satisfaction in their use on the basis of the sample of users who conducted the tests. The use of AR devices produces better results than paperwork in terms of efficiency and effectiveness, but not all devices produce appreciable results in terms of user satisfaction. Although AR technologies are mature, the tasks need to be carefully defined to avoid rejection phenomena. The strong expectation, that they generate in potential users, risks to remain disappointed today for some usability limits found in currently available devices. It is necessary to start testing in pilot applications in various industrial fields in order to capture in time and adequately support this opportunity of innovation in Italy.

The paper describes the activities of conceptual design of tools and procedures and the virtual simulation of the Remote Handling (RH) tasks provided in the maintenance of the systems present in the Access Cell (AC) of DONES (DEMO Oriented Neutron Source) facility. In particular, the RH maintenance of the Target Assembly (TA) is critical because of its position in the most severe region of neutron irradiation, the Test Cell (TC), where the material specimen are tested to understand the degradation of the materials properties throughout the reactor operational life. The main RH maintenance activity includes the replacement of the entire TA and the cleaning of the surfaces of connection in the TC. The cleaning operation is fundamental because it allows the removal of any lithium solid deposition from the surfaces: any further deposition on the surfaces could compromise the sealing of the TA. The RH is based on the idea of a reconfigurable modular chain of devices connected to the Access Cell Mast Crane (ACMC) located in the AC. To increase the modularity and to reduce the costs of the Remote Handling System (RHS), a telescopic boom is used equipped with a Gripper Change System (GCS) that allows the use of different end effectors. To perform the tasks, a Parallel Kinematic Manipulator (PKM) and a Robotic Arm (RA) are proposed, allowing the tools to move with more degree of freedom in the AC space. The modeling of the devices and the 3D kinematic simulations maintenance operations tasks were simulated and tested in virtual reality environment, aimed at developing and validating the implemented maintenance procedures, in collaboration with the IDEAinVR Laboratory of CREATE/University of Naples Federico II, and the research center at ENEA Brasimone, Italy. Copyright İ 2018 ASME

The Iterative and Participative Axiomatic Design Process (IPADeP) deals with the early conceptual design stage of complex mechanical assemblies. It provides a systematic approach based on the theory of Axiomatic Product Development Lifecycle and aims to minimize the risks related to the uncertainty and incompleteness of the requirements, considering that the requirements will be refined and completed during the process. IPADeP has an iterative nature and is focused on the experience of the people involved in the design process. The functional requirements and the design parameters are conceived through brainstorming sessions and the concept selection is performed involving several experts through a Multi Criteria Decision Making technique. IPADeP has been adopted as methodology to address the early conceptual design stage of a subsystem of the DEMOnstration fusion power plant: the divertor cassette-to-vacuum vessel locking system. A first iteration was performed, resulting in the selection of a "high level" rough solution. According with IPADeP this paper presents an improvement of this solution, performing a new iteration of the process, since the system is ripe to proceed with the decomposition and zigzagging to the second level and new requirements are coming in from the development of the interfaced systems. © 2015 The Authors. Published by Elsevier B.V.

This paper deals with pre-concept studies of DEMO divertor cassette-to-vacuum vessel locking system under the work program WP13-DAS-07-T06: Divertor Remote Maintenance System pre-concept study. An iterative design process, consistent with Systems Engineering guidelines and named Iterative and Participative Axiomatic Design Process (IPADeP), is used in this paper to propose new innovative solutions for divertor locking system, which can overcome the difficulties in applying the ITER principles to DEMO. The solutions conceived have been analysed from the structural point of view using the software Ansys and, eventually, evaluated using the methodology known as Fuzzy-Analytic Hierarchy Process. Due to the lack and the uncertainty of the requirements in this early conceptual design stage, the aim is to cover a first iteration of an iterative and incremental process to propose an innovative design concept to be developed in more details as the information will be completed.

This paper focuses on a preliminary structural analysis of the current concept design of DEMO vacuum vessel (VV). The VV structure is checked against a vertical load due to a Vertical Displacement Event in combination with the weight force of all components that the main vessel shall bear. Different configurations for the supports are considered. Results show that the greatest safety margins are reached when the tokamak is supported through the lower ports rather than the equatorial ports, though all analyzed configurations are compliant with RCC-MRx design rules.

Dip-Brazing is a metal-joining process in which two or more metal items are joined together using a low-temperature melting element as filler. In telecommunication field, this process is used to fabricate radar antenna systems. The process begins with the assembly of the parts constituting the antenna and the thin filler sheet used to join the parts. The mechanical deformations of the micro-pins of the parts allow to obtain a more compact mechanical assembly, before than the antenna system is subjected to an immersion cycle used for adjoining the parts. In this work, we present the design of the robotic cell to automate the assembly procedure in the aluminum dip-brazing of antenna in MBDA missile systems. In particular, we propose a robotic cell using two stations: i) assembly, using a SCARA manipulator; ii) riveting, using a three-axis cartesian robot designed for positioning a radial riveting unit. Motion control of the robots and scheduling of the operations is presented. Experiments simulated in a virtual environment show an almost perfect tracking of the designed trajectories. The standardization of the procedure as well as the reduction of its execution time is thus achieved for the industrial scenario.

Since 2014 preconceptual design activities for European DEMO divertor have been conducted as an integrated, interdisciplinary R&D effort in the framework of EUROfusion Consortium. Consisting of two subproject areas, ‘Cassette’ and ‘Target’, this divertor project has the objective to deliver a holistic preconceptual design concept together with the key technological solutions to materialize the design. In this paper, a brief overview on the recent results from the subproject ‘Cassette’ is presented. In this subproject, the overall cassette system is engineered based on the load analysis and specification. The preliminary studies covered multi-physical analyses of neutronic, thermal, hydraulic, electromagnetic and structural loads. In this paper, focus is put on the neutronics, thermohydraulics and electromagnetic analysis.

This paper presents the foundation of a new class of input shapers, designed using a predictive approach. The method is used to control the transient and residual vibrations in flexible nonlinear systems with time-varying parameters. The motivation is the development of simple algorithms and architectures for controlling the motion in flexible nonlinear systems with minimal modeling effort. The approach trains an artificial neural network to obtain closed-form expressions used for calculating, in real time, the amplitudes and the time locations of the impulses required by a common input — shaping technique. In this work we use this idea to design a command shaper for controlling the motion of the simplest flexible nonlinear system, an overhead crane with a suspended payload. We validate the approach using simulations and experiments. The benefits of such a control system will, in the end, enable using this method for controlling the motion of complex nonlinear systems, resulting in almost zero vibrations.

This paper presents eligere, a new open-source distributed software platform for group decision making in engineering design. It is based on the fuzzy analytical hierarchy process (fuzzy AHP), a multiple criteria decision making method used in group selection processes to rank a discrete set of alternatives with respect to some evaluation criteria. eligere is built following the paradigm of distributed cyber-physical systems. It provides several features of interest in group decision making problems: a web-application where experts express their opinion on the alternatives using the natural language, a fuzzy AHP calculation module for transforming qualitative into quantitative data, a database for collecting both the experts' answers and the results of the calculations. The resulting software platform is: distributed, interactive, multi-platform, multi-language and open-source. Eligere is a flexible cyber-physical information system useful in various multiple criteria decision making problems: in this paper we highlight its key concepts and illustrate its potential through a case study, i.e., the optimum selection of design alternatives in a robotic product design.

This paper is based on the remote maintenance system project (WPRM) for the demonstration fusion power reactor (DEMO). Following ITER, DEMO aims to confirm the capability of generating several hundred of MW of net electricity by 2050. The main objective of these activities is to develop an efficient and reliable remote handling (RH) system for replacing the divertor cassettes. This paper presents the preliminary results of the concept design of the divertor RH system. The proposed divertor mover is a hydraulic telescopic boom driven from the transportation cask through the maintenance tunnel of the reactor. The boom is divided in three sections of 4 m each, and it is driving an end-effector in order to perform the scheduled operations of maintenance inside the vacuum vessel. Two alternative design of the end effector to grip and manipulate the divertor cassette are also presented in this work. Both the concepts are hydraulically actuated, basing on the ITER previous studies. The divertor cassette end-effector consists of a lifting arm linked to the divertor mover, a tilting plate, a cantilever arm and a hook-plate. The main objective of this paper is to illustrate the feasibility of DEMO divertor remote maintenance operations.

This paper presents a nonlinear finite element formalism for modelling the dynamics of flexible manipulators using the special Euclidean group SE(3) framework. The method is based on a local description of the motion variables, and results in a singularity — free formulation which exhibits important advantages regarding numerical implementation. The motivation behind this work is the development of a new class of model — based control systems which may predict and thus avoid the deformations of a real flexible mechanism. Finite element methods based on the geometrically exact beam theory have been proven to be the most accurate to account for flexibility: in this paper we highlight the key aspects of this formulation deriving the equations of motion of a flexible constrained manipulator and we illustrate its potential in robotics through a simple case study, the dynamic analysis of a two-link manipulator, simulating different model assumptions in order to emphasize its real physical behavior as flexible mechanism.

The paper deals with the design issues concerning the remote maintenance of divertors in fusion advanced studies torus (FAST), a satellite tokamak acting as a test bed for the study and the develop of innovative technologies oriented to ITER and DEMO programs, pilot examples of the feasibility of energy production from nuclear fusion on the Earth. FAST remote handling (RH) solutions are provided according to an "interactive design review" philosophy based on virtual prototyping techniques. Assuming an ITER configuration as start point, it foresees an iterative process of design review, carried out in virtual reality (VR) environment and oriented to obtain a sort of best solution from the RH point of view. Any iteration includes the analysis of the current solution and the proposal of new and alternative ones, based on the requirements fulfillment and the improvement of critical points highlighted. In such a way, and this is the main novelty introduced by the paper, the interactive design review in a VR collaborative environment becomes the tool able to put in cooperation and in positive competition various and different competences, required by a multidisciplinary problem as the realization of nuclear fusion machine, in order to reach a shared solution. A first preliminary FAST RH solution is hereinafter presented, accompanied by the design of a compatible support system, due to the strict relationship between the divertor maintenance and the support configuration. The work was carried out via the collaboration of the "Divertor Test Platform 2" (DTP2) team, in charge of ITER divertor RH tests and located in VTT's Labs of Tampere (Finland), and the IDEAinVR team of CREATE Consortium, with competence in interactive design and VR simulations and located in the Virtual Reality Lab of University of Naples Federico II (Italy). © 2013 Springer-Verlag France.

This paper presents the role of distributed information systems in enhancing multiple criteria decision making problems. This goal is achieved showing the architecture and implementation of ELIGERE, a distributed software platform designed to rank a discrete set of alternatives with respect to multiple evaluation criteria. ELIGERE distributed architecture provides several features of interest in group decision making: a web-based interface where experts express their opinion, a remote computational module implementing a multiple criteria decision making method (fuzzy AHP) for ranking the alternatives, a database for collecting both the answer of the experts and the results of the calculations from the computational module. The motivation behind this work is to speed up the concept selection in product design. An illustrative example, the concept selection of a sensored platform for mobile robots, shows how the distributed architecture of ELIGERE results in an enhancement of the concept selection, in terms of both time and experts' interactive experience.

Aim of this study was to validate an inertial system able to detect the loss of ground contact (LOGC) in race-walking through outdoor tests in real training conditions. An inertial sensor was placed at L5/S1 of the vertebral column of a Italian national team athlete to acquire timing measurements of the LOGC. Data were encoded by a well-defined protocol. After a preliminary laboratory study, the athlete performed outdoor-field-tests at different velocities. A specific e-bike with a high-speed camera allowed to acquire a video and to validate sensor measurements. Results indicate that the inertial system can improve the accuracy in detecting the visible LOGC.

This paper describes a new motion analysis protocol for race-walking. The protocol has been tested under laboratory conditions on a real athlete of the Italian national race-walking team. The experimental setup included a motion capture system and a force platform to record both kinematic and dynamic aspects of the athletic action. Thus, any infringement of the rules can be detected, based on the measure of knee flexion-extension and the loss of ground contact. The biomechanical efficiency can be determined from the joint angles and the temporal components of gait. The results of experiments show that the protocol can be a valuable tool to assist athletes and trainers in improving race-walking technique.

The aim of the paper is to address an innovative methodology for assessing the usability of a product. This methodology is particularly suitable for designing products that provide their main functions through their control interfaces. In particular, this case study relates to the usability assessment of two control devices for a wheelchair-mounted robot manipulator to assist physically disabled people. The study focuses on defining a synthetic usability index on the basis of two currently used methods: the multi criteria decision analysis and the Saaty’s analytic hierarchy process. Several virtual reality (VR)-based experiments have been conducted, set up in accordance with a cross-array experimental plan, that adequately caters for both control and noise factors. Quantitative measures and subjective user evaluations have been collected to maximize the effectiveness, the efficiency and the satisfaction perceived by users while using the product. Compared to the literature on the subject, the proposed approach provides both more flexibility in defining quantitative indexes and more adequate results, even when involving only a small sample of users in the participatory design session. The use of VR technologies for the collection of the experimental data has been essential in terms of safety, costs and repeatability of the tests, as well as of the robustness with respect to noise factors.

The present paper deals with the manufacturing process of a railway carriage. In the first part of the paper, the authors focus on a “virtual railway factory” that uses a very innovative assembly cycle, if compared to the traditional manufacturing processes in the railway field. The case study refers to a railway carriage consisting of four modules, that are singularly set up of furnishings and other systems in dedicated workplaces. On one hand, the virtual simulation has highlighted several critical aspects to be improved, in order to achieve a greater feasibility and to reduce time and cost. On the other hand, the designers have been able to evaluate the movements of the parts and the assembly sequences of the components, by considering each geometric, functional and technological constraint and also some safety requirements. The second part of the paper deals with the simulation of the assembling operations and the analysis of tolerance chains, which have been performed through a Computer Aided Tolerancing system. In particular, the precision requirements have been also evaluated and we have compared the accumulation of dimensional and geometric deviations when using both rivets and traditional welds to fasten the modules.

In contexts in which mechanized harvesting is limited, such as in the northwestern Black Sea region of Turkey, it is important to improve timber harvesting productivity while preserving operators' safety and reducing environmental damage. This study aims to introduce a methodology in which the harvesting process is simulated with discrete-event simulation (DES) software in order to identify bottlenecks. An alternative process is compared to the original within the DES software, carrying out further steps oriented to the generation of new innovative product concepts. As a case study, the design of an innovative skidding winch is proposed. The development of the product was focused towards customer satisfaction by collecting customer requirements and identifying quality characteristics with a quality function deployment approach. Contradictions identified in the design phase were solved using the TRIZ contradiction toolkit, generating different product concepts. Inventive solutions provided by TRIZ were designed within parametric CAD software. The concepts were compared in a virtual environment, eventually selecting an optimal solution. The results showed that, with the concept adopted, it is possible to achieve a substantial increase in productivity, from 121% to 133%, in terms of kilograms of logs per hour deposited on the landing.

This paper deals with the development of a Knowledge Based Engineering (KBE) methodology for supporting a manufacturing company, in particular railway manufacturers, in their analyses for reusing existing products in new projects. The proposed methodology is based on the development of a Decision Support System (DSS) and the use of an analysis, called Adopt/Adapt/Innovate (AAI), aimed at identifying products already designed that fully or partly fit what required by new bids. The DSS is built within a PLM software and part of the research concentrated on comparing the PLM suites available in the market searching for the best tool able to act the role of a centralized management dashboard for knowledge reuse. DSS and AAI analysis are the base for future research activities for obtaining a KBE system that automatically models complex railway products starting from the customer requirements, drastically reducing the time to market.Copyright © 2015 by ASME

The main objective of this work was to design an innovative skidding winch aimed to improve timber harvesting productivity, operators’ safety, and reduce environmental damage in contexts in which mechanized harvesting is limited. The study area is the north-western Black Sea region of Turkey. In the proposed methodology, the harvesting process was simulated with Discrete Event Simulation (DES) software in order to identify bottlenecks. An alternative process was compared with the original one within the DES software itself in order to validate further steps oriented to generate new innovative product concepts. The development of the product was focused towards customer satisfaction, collecting customer requirements and identifying quality characteristics with a Quality Function Deployment approach. Contradictions identified in the design phase were solved using the TRIZ contradiction toolkit, generating different product concepts. Inventive solutions provided by TRIZ were designed within parametric CAD software. The concepts were compared in virtual environment with focus on ergonomics, selecting an optimal solution. The results show that with the concept adopted is possible to achieve a substantial increase in productivity, from 121% to 133%, in terms of kilograms of logs per hour deposited on the landing. Moreover, the final concept allows for ergonomic loading operations and reduces environmental damage to soil and vegetation.Copyright © 2015 by ASME

Divertor is a crucial component in Tokamaks, aiming to exhaust the heat power and particles fluxes coming from the plasma during discharges. This paper focuses on the optimization process of FAST divertor, aimed at achieving required thermo-mechanical capabilities and the remote handling (RH) compatibility. Divertor RH system final layout has been chosen between different concept solutions proposed and analyzed within the principles of Theory of Inventive Problem Solving (TRIZ). The design was aided by kinematic simulations performed using Digital Mock-Up capabilities of Catia software. Considerable electromagnetic (EM) analysis efforts and top-down CAD approach enabled the design of a final and consistent concept, starting from a very first dimensioning for EM loads. In the final version here presented, the divertor cassette supports a set of tungsten (W) actively cooled tiles which compose the inner and outer vertical targets, facing the plasma and exhausting the main part of heat flux. W-tiles are assembled together considering a minimum gap tolerance (0.1-0.5 mm) to be mandatorily respected. Cooling channels have been re-dimensioned to optimize the geometry and the layout of coolant volume inside the cassette has been modified as well to enhance the general efficiency. © 2015 Elsevier B.V. All rights reserved.

The present paper proposes a structured Product Development Lifecycle (PDL) model to deal with the concept design stage of complex assemblies. The proposed method provides a systematic approach to design, aimed to improve requirements management, project management and communication among stakeholders as well as to avoid project failures reducing project development time. This research also provides suggestions and recommendations for utilizing different analysis, synthesis and assessment methodologies along with the proposed approach. The process developed, named Iterative and Participative Axiomatic Design Process (IPADeP), is consistent with ISO/IEC 15288: 2008 – “Systems and software engineering”, and INCOSE Systems engineering handbook. It is an iterative and incremental design process, participative and requirements driven, based on the theory of Axiomatic Product Development Lifecycle (APDL). IPADeP provides a systematic methodology in which, starting from a set of experts’ assumptions, a number of conceptual solutions are generated, analysed and evaluated. Based on the results obtained, new iterations can be performed for each level of decomposition while product requirements are refined. In this paper, we applied IPADeP to the initial phase of conceptual design activities for DEMO divertor-to-vacuum vessel locking system in order to propose new innovative solutions.

The Fusion Advanced Study Torus (FAST) has been proposed as a high magnetic field, compact size tokamak providing a flexible integrated environment to study physics and technology issues in ITER and DEMO relevant conditions. FAST has a quite large natural toroidal field ripple (around 1.5%) due to its compactness and to the number of access ports: this ripple must be lowered to an acceptable level to allow safe operations and a good confinement quality. An Active Ripple Compensating System (ARCS) has been designed, based on a set of poloidal coils placed between the plasma chamber and the Toroidal Field Coils (TFCs). These ARCS coils will be fed with adjustable currents, opposite in direction respect to the TFC currents, and will allow lowering the ripple up to zero and beyond. The CAD model of FAST including the ARCS coils has been completed and preliminary electromagnetic and thermal analyses have been carried out. Moreover, a Feedback Active Control System (FACS) composed of two arrays of in-vessel saddle coils has been designed to allow safe high plasma current, low safety factor operation and to mitigate possibly large ELMs effects in FAST. These FACS coils will be fed by a feedback system to control MHD modes: a first engineering assessment of the current requirements has been carried out. © 2013 Euratom-ENEA Association sulla Fusione.

This paper focuses on a structured methodology that uses virtual reality (VR) and digital human modeling (DHM) to study maintenance procedures of industrial products. VR technologies help to highlight the most critical aspects of maintenance operations, while DHM tools allow detailing working sequences. Data coming from these analyses are then used to draw up a multimedia maintenance manual based on digital video animations, audio comments, explanatory images and written recommendations. Information is available to maintenance personnel directly on the working site through portable electronic devices. Further, web-based multimedia manuals can be updated on-line and help to shorten learning time and maintenance downtimes.

The ISO 9001: 2000 requires the phase of design validation in order to demonstrate that the design output are able to satisfy specified or forecasted user requirements; for this reason, generally, physical prototype are realized in order to evaluate real product performances and their correlation with simulated ones. In this paper, the use of virtual inspection probes to validate playground equipment design is studied, pointing out limits and defining the optimal test strategies. Through the use of Robust Design techniques the authors show that the combined use of real time shadows and positional sound feedback allows to reduce the percentage of wrong inspections in the validation phase of playground equipment design. The authors develop an inspection probe simulation tool in virtual immersive environment. In particular, this tool ensures the collision detection through visual and sound feedback and increases the realism of the immersive environment. Finally, an experimental session, using a physical prototype of playground equipment, is carried out in order to compare these results with the ones coming out from the VR experiments. For a standard entrapment test, the authors assess the dependences of false and missed alarm by the diameter of the openings to evaluate and establish an acceptability threshold for the usability of the virtual probes.

This paper deals with an application of virtual simulation within the manufacturing process of a high-speed train. This project was born from a need to reorganize the train assembly line of a rail transport engineering company. Nowadays, manufacturing firms need to improve productivity in terms of higher throughput, shorter lead time, low work-in-process and high resource utilization. Today, the use of a Discrete Event Simulation (DES) tool is common for supporting engineers in reaching these targets, representing a valid help in what-if analyses and in the measurement or validation of a solution. In this work, differently from the common use, it has been developed a virtual model whose function is not to measure and/or validate a solution of a problem, but to generate a solution that will be nearly to the optimum. This paper describes DES tools, the methodology used in this work, the case-study and the obtained results.

In this work we apply an innovative participative design approach for the quality evaluation of virtual prototypes of new industrial products (i.e. concept designs), by adopting statistical procedures and carrying out tests in an immersive VR environment. This methodology has been fully exploited through a case study concerning the choice of the optimal design for the interiors of a new regional train. Following this approach, the optimal concept design is defined at the end of a process consisting of five phases: identification of the quality elements of the concept design, classification of the quality elements, generation and quality evaluation of product concepts and, finally, definition of the optimal concept. According to the applied methodology after the identification of the customer’s needs, a structured set of quality elements has been defined and, successively, classified according to Kano’s theory. Following the approach of conjoint analysis, the design factors have been combined according to an experimental plan to form product virtual concepts. During the concepts generation phase we have explored those product architectures that integrate design characteristics correlated to the set of quality elements. The concepts have been created according to comfort, ergonomic and safety criteria. In particular we have considered the ergonomics of places and furniture dimensions, through the use of virtual manikins. The evaluation of the quality of the different concepts has been carried out in the VR laboratory (named “VRTest”) of the Competence Centre for the Qualification of Transportation Systems founded by Regione Campania according to an original statistical procedure and has involved a group of experts in train’s interiors design and a group of common users of regional trains.Copyright © 2012 by ASME

Nowadays, economical, technical and ergonomic factors have a great importance on the design of the agricultural tractors. The paper illustrates the use and the management of heterogeneous product information (manual measurements and drafts, 2D drawings, technical documentation, photos), advanced CAD modeling tools and digital human models, for the redesign and the ergonomic optimization of an agricultural tractor’s driver cab. The project development has been organized using a top–down approach in a collaborative environment. At first, a manual measurement with gauges allowed to realize a technical draft of the whole agricultural tractor and of each component part of the driver cab. Then a main skeleton has been created in Catia V5 environment in order to specify all the datum elements necessary to model each sub-assembly of the tractor. Cabin, platform, engine, tires, seat, dashboard and controls have been organized separately and modeled considering the details related to the manual measurements and to the technical standards. Once obtained the 3D CAD model of the tractor, an opportune questionnaire was prepared and a test campaign was carried out with real operators in order to define the more critical control devices within the driver cab, as regards to usability and ergonomic issues. An “Ergonomics’ Evaluation Index” (EEI) was defined taking into account the posture angles of the operator and the Rapid Upper Limb Assessment analysis tool available in the “Ergonomics Design & Analysis” module of Catia V5 based on the use of a digital human model. The index was validated comparing the results of tests carried out using virtual manikins of different percentiles performing a specific driving task, with the results of tests carried out by real operators, of the same percentiles, performing the same driving task. Critical values of the EEI obtained during some driving tasks in virtual environment, suggested to modify the shape and the position of some control devices in order to optimize the ergonomics of the driver cab. The adoption of the top-down modeling based approach allowed each change on a singular component part to be automatically propagated on the whole assembly, making easy the changes on the virtual prototype.Copyright © 2012 by ASME

An algorithm for both human-like motion generation and joint torques computation for digital humans is addressed in this paper. This goal has been achieved using techniques derived from robotics. In particular, the so-called augmented Jacobian has been used to solve the inverse kinematics problem with a single closed loop inverse kinematics algorithm. Furthermore, a position control for the center of mass of the kinematic chain, and for its projection on the support plane (center of pressure), has been implemented to achieve easy posture control. Thus, the inverse kinematics can be solved taking into account the static balance of the digital human. Moreover, the proposed algorithm allows simulating quite complex tasks, which involve the motion of the whole body, by means of only few task-related control points arbitrary located on the whole kinematic chain. The resulting movements are quite natural even for complex tasks as can be seen on the simulation experiments reported which show the effectiveness of the proposed approach. Finally, the joint torques can be computed thanks to the kinetostatics duality: the results are in accordance with biomechanical analyses.

The preventive knowledge of serviceability times is a critical factor for the quantification of after-sales services costs of a vehicle. Predetermined motion time system are frequently used to set labor rates in industry by quantifying the amount of time required to perform specific tasks. The first such system is known as Methods-time measurement (MTM). Several variants of MTM have been developed differing from each other on their level of focus. Among them MTM-UAS is suitable for processes that average around 1–3 min. However experimental tests carried out by the authors in Elasis (Research Center of FIAT Group) demonstrate that MTM-UAS is not the optimal approach to measure serviceability times. The reason is that it doesn’t take into account ergonomic factors. In the present paper the authors propose to correct the MTM-UAS method including in the task analysis the study of human postures and efforts. The proposed approach allows to estimate with an “acceptable” error the time needed to perform maintenance tasks since the first phases of product design, by working on Digital Mock-up and human models in virtual environment. As a byproduct of that analysis, it is possible to obtain a list of maintenance times in order to preventively set after-sales service costs.

Robots designed to operate in everyday domains have to move in environments designed for the humans. Therefore, they will often have a humanoid kinematic structure. Simple and efficient kinematic models are needed for motion control of this class of robots. An algorithm is presented to solve the inverse kinematics problem in the presence of a number of control points arbitrarily located on the whole robot body, using an augmented Jacobian approach and including posture control. Simulation experiments are reported, showing the effectiveness of the proposed approach.

The paper represents the contribution to the PUODARSI (Product User-Oriented Development based on Augmented Reality and Interactive Simulation) research project in the development of a design environment which integrates modeling tools and CAE simulation capabilities. Typically, aerodynamic and mechanical performances of the object shape are in contrast with the stylistic requirements. Integrated tools and numerical simulations are then needed to support designers during the conceptualization of a new shape or when re-designing a product. This work combines Reverse Engineering methodologies and CAE tools to easily analyze the interaction between the aerodynamic behavior and the stress-strain state, due to viscous and pressure loads, of a physical object. A friendly interactive tool, based on MatLAB® and linked to Comsol Multiphysics®, was developed to drive user during the simulation and the visualization of results.

The paper aims at providing a methodological contribution to the concept design of train interior in order to improve the quality perceived by users in compliance with railway standards. Indeed, the combined use of advanced CAD tools, experimental statistical methods and Virtual Reality tools allows developing, selecting and experimentally evaluating new concepts. The design cycle starts both from designers’ proposal and the identification of user’s needs; then, it makes use of datum-based CAD models in order to generate virtual concepts that satisfy railway standards; the cycle proceeds with the immersive evaluation of virtual prototypes, performed by potential and expert users in Virtual Reality. The identification of the optimal concept closes the design process. This procedure can be iterated in order to improve the quality of train interiors, evaluated thanks to the user’s involvement in the design cycle. In this work a case study on seat design of a regional train is presented, developed at the Virtual Reality laboratory, named VRTest, of the Regional Centre for the qualification of transportation systems set up by Campania Regional Authority.

The VR technology can be considered the most powerful tool introduced into the design process in order to realise immersive and interactive experience in the virtual world. Since earliest applications, both in the industrial engineering and civil architecture fields, the VR environment has anticipated, for the first time, the interaction of designers with new concepts at the first stages of the design process. The simulated interaction has enabled design team to be timely conscious of design faults and to provide project improvements or to develop innovative learning platform for highly specialised operators. The combination of direct 3D-interaction, 3D-visualization and 3D-devices makes, in prospective, VR an ideal medium for all “designing” tasks, from the conceptual phase to the detailed design phase. The positive results obtained from the first applications of VR technologies in automotive field have confirmed, to the industrial world, how these tools can be useful, potentially and in practice, to improve the quality of new industrial products and to develop new methodologies and new training procedures. Design for virtual styling, usability, ergonomics, maintainability, mechanical assembly/disassembly and crashworthiness, and ‘learning by virtual doing’ approach are significant examples. While in the classical design paradigm the design team explicitly takes into account the object and implicitly the user, in the VR environment the design team can simulate the interaction between the systemand real users as awhole. This is a crucial point. The design team has assumed, designing in

The present work deals with the re-designing of a locomotive, according to in force European standards, in the field of active and passive safety. The paper illustrates the use and the management of heterogeneous product information (2D drawings, technical documentation, photos), Virtual Reality tools and digital human models, for the re-designing of a locomotive, using a collaborative approach with a total absence of the reference digital models. The project development has been organised using a top–down approach in a collaborative environment. Finally, by means of the digital prototype of locomotive, a series of aesthetic, functional and ergonomic analyses, in virtual environment, has been performed.

The paper deals with the development of a methodology for studying, in a virtual environment, the ergonomics of a work cell in an automotive manufacturing system. The methodology is based on the use of digital human models and virtual reality techniques in order to simulate, in a virtual environment, human performances during the execution of assembly operations. The objective is to define the optimum combination of those geometry features that influence human postures during assembly operation in a work cell. In the demanding global marketplace, ensuring that human factors are comprehensively addressed is becoming an increasingly important aspect of design. Manufacturers have to design work cells that conform to all relevant Health and Safety standards. The proposed methodology can assist the designer to evaluate the performance of workers in a workplace before it has been realized. The paper presents an analysis of a case study proposed by COMAU, a global supplier of industrial automation systems for the automotive manufacturing sector and a global provider of full maintenance services. The study and all the virtual simulations have been carried out in the Virtual Reality Laboratory of the Competence Regional Center for the qualification of transportation systems (CRdC “Trasporti” - www.centrodicompetenzatrasporti.unina. it), which was founded by the Campania region with the aim of delivering advanced services and introducing new technologies into local companies operating in the field of transport.

The early identification of the optimal concept is a critical task of the design process in order to increase the chances of satisfying customers. The challenging aspect of the approach proposed in this work relies in the quality evaluation of virtual prototypes of new industrial products (i.e. concept designs) by adopting a statistical procedure previously applied to service industries. Following this approach, the optimal concept design is defined at the end of a process consisting of five phases: identification of the quality elements of the concept design, classification of the quality elements, generation and quality evaluation of product concepts and, finally, definition of the optimal concept. Currently, virtual reality (VR) environment offers the opportunity to evaluate the characteristics of different virtual prototypes by involving experts and/or customers, overcoming the need for several physical prototypes. On the other side, the dynamics of simulation and the stereoscopic visualization in VR environment provides a more realistic and impressive interaction with virtual prototypes than in CAD environment. The proposed methodology is fully exploited through two case studies: the choice of the optimal design for a traditional Neapolitan coffee maker, addressed by the Italian designer Riccardo Dalisi, and for a subassembly of a new minicar.