Product design is an iterative process that involves, among other things, evaluation. In addition to the intended functionality of the product, its affective properties (or “Kansei”) have emerged as important evaluation criteria for the successful marketing of the product. Affective properties refer to consumers' psychological feelings about a product, and they can be mapped into perceptual design elements for possible design modification toward higher customer satisfaction. Affective properties of products in design can partially be assessed using the near photorealistic graphic rendering feature of the desktop computer-aided design tools, or rapid prototyping tools that can produce physical mock-ups. Recently, immersive virtual reality systems have been suggested as an ideal platform for affective analysis of an evolving design because of, among other things, the natural style of interaction they offer when examining the product, such as the use of direct and proprioceptive interaction, head tracking and first-person viewpoint, and multimodality. In this paper, the effects of tactile augmentation and self-body visualization on the evaluation of the affective property are investigated by comparing three types of virtual environments for evaluating the affective properties of mobile phones. Each virtual environment offers different degrees of tactile and self-body realism. The effectiveness of these virtual environments is evaluated, compared to a control condition: the affective assessment of using the real product. The experiment has shown that the virtual affective evaluation results from the three systems correlated very highly with that of the real product, and no statistically significant differences could be found among the three systems. This finding indicates that tactile augmentation and the high-fidelity self-body visualization had no effect on the evaluation of the affective property. Nevertheless, the experimental results have indicated the importance of enhanced interaction with tactile augmentation for evaluating the property of texture, and have shown that VR systems have the potential for use as affective evaluation platforms.

The problem of teleoperating a mobile robot using shared autonomy is addressed: An onboard controller performs close-range obstacle avoidance while the operator uses the manipulandum of a haptic probe to designate the desired speed and rate of turn. Sensors on the robot are used to measure obstacle-range information. A strategy to convert such range information into forces is described, which are reflected to the operator's hand via the haptic probe. This haptic information provides feedback to the operator in addition to imagery from a front-facing camera mounted on the mobile robot. Extensive experiments with a user population both in virtual and in real environments show that this added haptic feedback significantly improves operator performance, as well as presence, in several ways (reduced collisions, increased minimum distance between the robot and obstacles, etc.) without a significant increase in navigation time.

The use of virtual-reality technology in the areas of rehabilitation and therapy continues to grow, with encouraging results being reported for applications that address human physical, cognitive, and psychological functioning. This article presents a SWOT (Strengths, Weaknesses, Opportunities, and Threats) analysis for the field of VR rehabilitation and therapy. The SWOT analysis is a commonly employed framework in the business world for analyzing the factors that influence a company's competitive position in the marketplace with an eye to the future. However, the SWOT framework can also be usefully applied outside of the pure business domain. A quick check on the Internet will turn up SWOT analyses for urban-renewal projects, career planning, website design, youth sports programs, and evaluation of academic research centers, and it becomes obvious that it can be usefully applied to assess and guide any organized human endeavor designed to accomplish a mission. It is hoped that this structured examination of the factors relevant to the current and future status of VR rehabilitation will provide a good overview of the key issues and concerns that are relevant for understanding and advancing this vital application area.

Although much research work has focused on identifying different factors that affect presence, it is still not clear how to effectively combine these results to create a content with high presence with respect to a given hardware set-up and limited computing resources. This paper proposes a concept of level of presence (LOP) in which we attempt to select a set of presence elements and their levels to maximize their “contribution” toward the overall presence subject to system resources. Such an optimization scheme would require a reasonable characterization of the computational costs and a sufficient knowledge of the relative and collective merits of various presence elements. We made an attempt to apply the LOP concept to VR system design for a particular application, a virtual fish tank. The purpose of this study is to assess the usefulness of the LOP concept and introduce science into content creation. We selected two important presence elements—the field of view (FOV) and the simulation level of detail (SLOD)—and quantified their costs in terms of the required computation time. Next, we ran a simple experiment to quantify the relative benefits of those two presence factors. For this application, it was found that providing more lifelike simulation, for instance, incurred needlessly expensive computations compared to the amount of increased benefits. Based on the result, the virtual fish tank was configured with the appropriate FOV and SLOD for maximum presence under different conditions, such as the preferred frame rate and total number of objects. We discuss the merits of such a presence-driven VR system development approach.

The development and maintenance of a virtual reality (VR) system requires indepth knowledge and understanding in many different disciplines. Three major features that distinguish VR systems are real-time performance while maintaining acceptable realism and presence, objects with two clearly distinct yet inter-related aspects like geometry/structure and function/behavior, and the still experimental nature of multi-modal interaction design. Until now, little attention has been paid to methods and tools for the structured development of VR software that addresses these features. Many VR application development projects proceed by modeling needed objects on conventional CAD systems, then programming the system using simulation packages. Usually, these activities are carried out without much planning, which may be acceptable for only small-scale or noncritical demonstration systems. However, for VR to be taken seriously as a media technology, a structural approach to developing VR applications is required for the construction of large-scale VR worlds, and this will undoubtedly involve and require complex resource management, abstractions for basic system/object functionalities and interaction tasks, and integration and easy plug-ins of different input and output methods. In this paper, we assembled a comprehensive structured methodology for building VR systems, called CLEVR (C oncurrent and LE vel by Level Development of VR System ), which combines several conventional and new concepts. For instance, we employ concepts such as the simultaneous consideration of form, function, and behavior, hierarchical modeling and top-down creation of LODs (levels of detail), incremental execution and performance tuning, user task and interaction modeling, and compositional reuse of VR objects. The basic underlying modeling approach is to design VR objects (and the scenes they compose) hierarchically and incrementally, considering their realism, presence, behavioral correctness, performance, and even usability in a spiral manner. To support this modeling strategy, we developed a collection of computeraided tools called P-VoT (P OSTECH -V irtual reality system devel o pment T ool ). We demonstrate our approach by illustrating a step-by-step design of a virtual ship simulator using the CLEVR/P-VoT, and demonstrate the effectiveness of our method in terms of the quality (performance and correctness) of the resulting software and reduced effort in its development and maintenance.

Training is usually regarded as one of the most natural application areas of virtual reality (VR). To date, most VR-based training systems have been situation based, but this paper examines the utility of VR for a different class of training: learning to execute exact motions, which are often required in sports and the arts. In this paper, we propose an interaction method, called Just Follow Me ( JFM ), that uses an intuitive “ghost” metaphor and a first-person viewpoint for effective motion training. Using the ghost metaphor (GM), JFM visualizes the motion of the trainer in real time as a ghost (initially superimposed on the trainee) that emerges from one's own body. The trainee who observes the motion from the first-person viewpoint “follows” the ghostly master as closely as possible to learn the motion. Our basic hypothesis is that such a VR system can help a student learn motion effectively and quickly, comparably to the indirect real-world teaching methods. Our evaluation results show that JFM produces training and transfer effects as good as—and, in certain situations, better than—in the real world. We believe that this is due to the more direct and correct transfer of proprioceptive information from the trainer to the trainee.