Virtual reality approaches for immersive design

The current application of virtual reality (VR) systems in the design process is limited mostly to design review. The reason for this limitation is the different data formats used for CAD and VR visualization. To use the benefits of VR during the design process, solutions for immersive design, the model manipulation inside the VE based on CAD data, are required. There are different approaches allowing VR systems to work as an active development platform. Three examples introduce the realization of the integration of CAD and VR software at different levels by the online coupling of complete applications or by integration of CAD core functionalities in VR systems.     

VirDe: a new virtual reality design approach

Virtual reality (VR), even if it does not represent any more a novel technology, is one of the most powerful tool to help designers during the development of new projects. This is proved by very numerous research activities related to this field. In this research, we have studied a new way to approach the development of a product. We present the ongoing development of a system, called VirDe, acronym of virtual design, which can allow the designers to perform the whole design process, from the modelling phase to the finite element method (FEM) simulation analysis, in a virtual reality environment. This new method allows remarkable time and money saving in the overall product design process, but the most important contribution of VirDe is that, as far as we concerned, there is no known similar approach which has been studying the simultaneous combination of CAD, FEM and virtual environment (VE).     

A bi-directional interface for improved interaction with engineering models in virtual reality design reviews

Leveraging virtual reality (VR) technology to enhance engineering design reviews has been an area of significant interest for researchers since the advent of modern VR. The ability to interact meaningfully with 3D computer-aided engineering models in these VR design reviews is an important, though often neglected, capability due to the difficulty of performing data translation between native computer-aided design (CAD) data and VR compatible file formats. A bi-directional interface was developed between a VR design review environment and a commercial CAD package that streamlines the data translation process. Transmitting both geometric data and selected metadata from the CAD system enabled the development of enhanced model interaction tools in a VR design review application. User experiments were performed that compared the enhanced tools developed to a baseline toolset. Participants success using these toolsets was measured as they performed tasks related to design understanding and decision making, such as counting the number of gears in a gearbox or evaluating the feasibility of a proposed design change in a four-cylinder engine. The analysis of the data from these experiments showed a statistically significant improvement in participants ability to understand the geometry of the model correctly, confidently, and quickly, as well as in participants ability to correctly and confidently understand the implications of a proposed design change when using the Enhanced Toolset. We conclude that the bi-directional interface concept developed in this work can be extended to enable advanced interaction with a diversity of engineering data in VR.     

A comparative evaluation of human interaction for design and assembly of 3D CAD models in desktop and immersive environments

Computer aided design (CAD) systems have become today the basic tools used to design and develop products in the industry. In current CAD software most of the editing commands are issued with the aid of widgets and alphanumeric data input devices, while research community is proposing the use of virtual reality environments for CAD modelling. This paper presents an experimental study which compares the performance and usability of a multimodal immersive VR (virtual reality)-CAD system with a traditional CAD system. A comparative analysis was done for the modelling and the assembling process of 3D models. The results obtained from this investigation have shown that, in spite of the variety of interface devices in the virtual environment which provide a natural interaction to the user, the modelling time is about the same compared with a traditional desktop interface. The assembling time, however, is shown to be much smaller for multimodal system. Furthermore, the multimodal interface poses a higher physical stress factor, the hand movement distance being on average 1.6–2.3 times greater than the desktop interface for modelling process and assembling process, respectively. A post-experiment questionnaire shows that the multimodal system produce a great satisfaction for users in modelling and assembly processes.     

Interactive simulation of CAD models assemblies using virtual constraint guidance

In the context of virtual reality (VR) and of computed aided design (CAD), haptic simulations are used to perform assembly tasks between 3D objects. To ensure the good assembly of those objects, we propose a new method of interactive assembly that uses both kinematic constraints and guiding virtual fixtures. Modelling a haptic assembly task as a combination of mechanical joints, we focus on the guidance of objects and on the activation cues of kinematic constraints in physical simulation. In this article, we first outline the difficulties related to the haptic-assembly of CAD objects in VR simulation. Introducing the virtual constraint guidance (VCG), we present a new method for haptic guidance that decomposes a task in two independent steps: a guiding step which use geometries as virtual fixtures to position objects, and a functional step which use kinematic constraints to perform the assembly task. We finally present a complete application of our method on a peg-in-hole insertion task.     

Virtual reality aided design of parts and assemblies

Current virtual reality (VR) systems provide an enormous potential for enhancing the visualization of 3D-design drafts. Based on new navigation techniques the designer is able to interact, model in a more intuitive and efficient way. In our contribution we present a novel interaction metaphor that facilitates the synthesis of efficient virtual reality interaction and visualization techniques with modern feature based CAD systems. We present “NAVIMODE”, an alternative approach for navigation, manipulation and selection, to combine the advantages of VR and CAD systems. The design engineer has the chance to design in his/her habitual environment using the advantage of virtual reality concurrently.     

A new product design method based on virtual reality, gaming and scenarios

Through the years, many methods and tools have been developed that support designers in creating good products. Current trends, for example, are to use virtual reality (VR) simulation, gaming principles, and scenario based techniques during product design processes. Each of these methods and tools contributes to the potential effectiveness and efficiency of product design processes. However, in current practice, they are often applied in an ad-hoc manner. This paper presents a new product design method that integrates elements of a number of important trends in contemporary product design processes. Using VR simulation, gaming principles and scenarios, the new product design method gives non-designers (e.g. users, production engineers, marketing managers, maintenance workers) a proactive role in the design process. Within a dedicated design environment, all stakeholders are allowed to create their own designs and immediately test these in a wide variety of use scenarios. By letting stakeholders realistically interact with their personal creations, designers can quickly and reliably pinpoint their needs and preferences. At the same time, good designs are generated. The new product design method was applied to the design of a lane change support system; a system that supports the driver of a vehicle in performing lane change maneuvers. Using the design environment that was established for this case, the designer was able to get a consistent image of everyone's preferences as well as to draw a reliable conclusion about what would be a good design.     

Improving design validation of playground equipment in virtual reality

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.     

Turning virtual reality into reality: a checklist to ensure virtual reality studies of eating behavior and physical activity parallel the real world

Virtual reality (VR) provides a potentially powerful tool for researchers seeking to investigate eating and physical activity. Some unique conditions are necessary to ensure that the psychological processes that influence real eating behavior also influence behavior in VR environments. Accounting for these conditions is critical if VR-assisted research is to accurately reflect real-world situations. The current work discusses key considerations VR researchers must take into account to ensure similar psychological functioning in virtual and actual reality and does so by focusing on the process of spontaneous mental simulation. Spontaneous mental simulation is prevalent under real-world conditions but may be absent under VR conditions, potentially leading to differences in judgment and behavior between virtual and actual reality. For simulation to occur, the virtual environment must be perceived as being available for action. A useful chart is supplied as a reference to help researchers to investigate eating and physical activity more effectively.     

Virtual concepts and experiments to improve quality of train interiors

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.     

Product–process interface for manufacturing data management as a support for DFM and virtual manufacturing

In order to tackle a continuous improvement of virtual engineering, product modelling has to integrate more knowledge that refers to every decision taken during the product development process. Those decisions have to be related to the assessment of the whole product life cycle. This paper particularly addresses the domain of product’s industrialisation that aims at selecting the manufacturing processes. This selection must currently be done as soon as possible and has to be strongly linked with product definition and computer aided design (CAD) modelling. This work first presents some new results concerning a product–process interface to integrate manufacturing information in the product model and how it leads to the definition of the CAD model. Then this interface that also manages specific information coming from the manufacturing process (tolerances, stresses gradient...) is used to improve the whole manufacturing process plan simulation. This process plan has, indeed, to track every material transformation issued from each manufacturing operation.     

Design of an innovative assembly process of a modular train in virtual environment

In this paper we present an innovative assembly cycle of railway vehicles that can improve the manufacturing process. The study was carry out using virtual reality (VR) technologies in the VR Laboratory of the Competence Regional Centre for the qualification of transportation systems set up by Campania Regional Authority. Using the developed simulation environment we were able to evaluate different workplaces layout configurations of the train assembly cycle. The best workplace layout configuration was detected in order to minimize the lead time in the production line and optimize the automation level and human component for each workplace.     

Training older adults with virtual reality use to improve collision-avoidance behavior when walking through an aperture

Many older adults perform collision-avoidance behavior either insufficiently (i.e., frequent collision) or inefficiently (i.e., exaggerated behavior to ensure collision-avoidance). The present study examined whether a training system using virtual reality (VR) simulation enhanced older adults’ collision-avoidance behavior in response to a VR image of an aperture during real walking. Twenty-five (n = 13 intervention group and n = 12 control group) older individuals participated. During training, a VR image of walking through an aperture was projected onto a large screen. Participants in the intervention group tried to avoid virtual collision with the minimum body rotation required to walk on the spot through a variety of narrow apertures. Participants in the control group remained without body rotation while walking on the spot through a wide aperture. A comparison between pre-test and post-test performances in the real environment indicated that after the training, significantly smaller body rotation angles were observed in the intervention group. This suggests that the training led participants to modify their behavior to try to move efficiently during real walking. However, although not significant, collision rates also tended to be greater, suggesting that, at least for some participants, the modification required to avoid collision was too difficult. Transfer of the learned behavior using the VR environment to real walking is discussed.     

Interaction and evaluation tools for collaborative virtual environment

The design of the virtual environment (VE) has to take into account several factors including the input and output devices, the design of the interaction metaphor and the application domain. In addition to these considerations, the design of collaborative virtual environment (CVE) needs to take into account the collaborative aspect of the interaction metaphor. in one hand, the interaction metaphor must be designed to produce the most possible task performance. In the other hand, the influence of the interaction metaphor on the user’s experience (in terms of psychological and social considerations) constitutes an important research question. To address this research question, we presented a new user-centred method for Collaborative Virtual Environments in taking into account human factors. Our goal is to study the effect of 3D interaction metaphors in CVE on copresence, involvement, awareness and collaborative effort.     

An interactive design approach for nuclear fusion purposes: remote handling system for FAST divertor

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).     

Development of and Feedback on a Fully Automated Virtual Reality System for Online Training in Weight Management Skills

Virtual reality (VR) technology can provide a safe environment for observing, learning, and practicing use of behavioral weight management skills, which could be particularly useful in enhancing minimal contact online weight management programs. The Experience Success (ES) project developed a system for creating and deploying VR scenarios for online weight management skills training. Virtual environments populated with virtual actors allow users to experiment with implementing behavioral skills via a PC-based point and click interface. A culturally sensitive virtual coach guides the experience, including planning for real-world skill use. Thirty-seven overweight/obese women provided feedback on a test scenario focused on social eating situations. They reported that the scenario gave them greater skills, confidence, and commitment for controlling eating in social situations.     

User-centered design of a virtual reality exhibit for archaeological museums

Nowadays, the adoption of virtual reality (VR) exhibits is increasingly common both in large and small museums because of their capability to enhance the communication of the cultural contents and to provide an engaging and fun experience to its visitors. The paper describes a user-centered design (UCD) approach for the development of a VR exhibit for the interactive exploitation of archaeological artefacts. In particular, this approach has been carried out for the development of a virtual exhibit hosted at the “Museum of the Bruttians and the Sea” of Cetraro (Italy). The main goal was to enrich the museum with a playful and educational VR exhibit able to make the visitors enjoy an immersive and attractive experience, allowing them to observe 3D archaeological artefacts in their original context of finding. The paper deals with several technical issues commonly related to the design of virtual museum exhibits that rely on off-the-shelf technologies. The proposed solutions, based on an UCD approach, can be efficiently adopted as guidelines for the development of similar VR exhibits, especially when very low budget and little free space are unavoidable design requirements.     

Application of the CMII model to an integrated engineering and manufacturing development environment

In all product development cycles, the change process is one of the most critical elements which must be well controlled. This change process, which is comprised within the configuration management methodology, must be one of the key processes supported by an integrated product development environment which supports the concurrent development of design and manufacturing. The CMII business process model proposed by the Institute of Configuration Management is very well documented and has become a reference for modelling the change process within an enterprise. It was thus proposed to evaluate how this model can be implemented within a virtual product development laboratory at école Polytechnique de Montréal which integrates CAD, PDM and MPM technologies. MPM technologies support manufacturing engineers and process planners for the development and analysis of all manufacturing process information. The study has shown that the CMII business model is totally compatible with the methodologies and technologies supported in the laboratory, but that the existing technologies have to support more sophisticated workflow capabilities to support the CMII model. Moreover, the model was found to foster a highly collaborative product and manufacturing process development environment where both engineering and manufacturing information structures are kept synchronized in real time.     

Efficacy of stereoscopic visualization and six degrees of freedom interaction in preoperative planning of total hip replacement

The aim of this study was to assess the accuracy of a six-degrees-of-freedom application for pre-operative planning of total hip replacement in a virtual reality (VR) environment. A test was performed estimating the system inherent accuracy. The users can move objects in the VR environment with an intrinsic accuracy almost four orders of magnitude greater than the object dimension. A second unambiguous and relevant task was defined to assess the accuracy achievable with the interface in a specific planning task. The results were compared with those obtained with 2D interfaces for both the stem and the cup component. The RMSE was assumed as an indicator of the achievable accuracy. The accuracy of the immersive interface was comparable with that achievable with a standard mouse - monitor interface. The users were consistent using the VR interface, confirming the high usability of the new interface and the steep learning curve of users unfamiliar with the new environment. This study has demonstrated that the application of VR environment for pre-operative planning of total hip replacement may help to shorten the duration of the positioning and to yield consistent results even with first-time users.