This paper proposes the concept of the hybrid information space that integrates the information space seamlessly between the real world and the virtual world, and the prototype system was developed. In this system, the users can communicate with each other between the real world and the virtual world or they can achieve their work while going and coming between both worlds. This system was applied to relive travel experiences and to assist campus navigation, and the effectiveness of this system was evaluated.

Recently, PC clusters have been used to construct CAVE-like immersive projection displays. However, in order to improve the rendering performance of PC cluster-based CAVE systems, the number of node PCs should be increased in accordance with the number of screens that are included. In this research, a mechanism for dynamic load-balanced rendering in a PC cluster system incorporating an arbitrary number of nodes was developed. This system constructs the cluster system by using a chain connection-type compositor board, whereby load-balancing can be controlled dynamically in response to the movement of the virtual objects or of the user's viewpoint. This paper describes the implementation of this dynamic load-balanced rendering method and presents the results of an evaluation experiment.

In this study, a remote presentation system that can be used in the shared immersive virtual world was developed This system consists of several elemental technologies, such as the video avatar, a shared database, shared visualization tools and an i-mode interface, and can be used for both meeting-style and demonstration-style presentations. This system was applied to a presentation of collaborative research in the field of fluid dynamics analysis, and the effectiveness was evaluated.

When a 3D object is designed in a virtual world, it is essential that the designer can observe and manipulate the object directly in 3D space. The aim of our study is to develop a virtual workplace in which 3D virtual objects can be observed from various directions and can be touched directly by utilising force feedback. In this paper, we propose a 3D modelling system that consists of an inclined three-screen display and a force feedback device. Using this system, we propose a force feedback grid that extends the concept of 2D CAD manipulation to a grid that can be used in a 3D space, and which integrates with force feedback in order to support modelling in the 3D space. Finally, we report the results of an experiment that we conducted in order to verify the effectiveness of the force feedback grid.

Describes the design and implementation of an artificial force display for immersive projection displays (IPD) such as CAVE or CABIN. In order to give the user maximum freedom of motion in the large virtual space generated by an IPD, it is necessary to use a portable force display that is self-contained on the user's body. Therefore, we developed a wearable force display called HapticGEAR. It is a backpack-type device that transmits applied forces to the wearer by using a wire-tension mechanism. The device is designed such that it minimizes fatigue for the wearer and does not interrupt the user's motion and view. Also, we integrated the device into CABIN and experimentally evaluated both the accuracy it achieved in tracing objects and the displayed haptic sensation.

Immersive projection displays such as CABIN and COSMOS have been connected through a broadband network. This kind of network environment is expected to be used as a multimedia virtual laboratory. In particular, video avatar technology has been developed in order to realize high-presence communication in this multimedia virtual laboratory. A video avatar is a computer-synthesized 3D image created using live video. This method has the characteristics of being a natural, accurate and convenient communication tool. In this study, the communication capabilities of the video avatar were experimentally evaluated. In addition, the video avatar technology was applied to several communications applications, such as that of guiding colleagues and undertaking design work in networked immersive projection displays.

The immersive projection display, CABIN was connected to several similar displays via an ATM network. In order to share the virtual world with a high quality of presence, transmitting the user's figure is a key technology. In this study, a 2.5 D video avatar method was developed. The user's figure is captured by stereo cameras and it is superimposed on the shared virtual world as the 2.5 D video avatar. In addition, the pointing accuracy using the 2.5 D video avatar was experimentally evaluated.

We describe the design and the implementation of a force display for immersive projection displays. To give the user maximum freedom of motion in a large working space, it is necessary to use a portable force display that is grounded on the user's body. Therefore, we developed a portable (wearable) force display called HapticGEAR which makes use of the tension of wires grounded on the user's back. This device is designed to reduce user's fatigue and to have fewer influence on the user's motion and sight.