The authors have developed a tangible navigation interface to assist navigation in VR(Virtual Reality) space. The aim of this paper is to show our interface is effective on spatial perception. For this purpose, experiments to compare the tangible navigation interface and the game controller were conducted. The results showed that the tangible navigation interface is superior in spatial perception because; 1) a user can always be aware of the bird's-eye view of the VR space, and 2) somatic sensation of a user's arm helps him/her to memorize spatial orientation and distance.

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In order that the society to be in readiness for emergency such as severe earthquakes, it is important to introduce the capability of sharing the common pictures among the command and control systems of different organizations, and also it is essential to train the ability of awareness and decision making of commanders. This paper proposes a new method to develop distributed virtual environment for commander's decision making training systems in disaster operations. In this method, simulators are provided for each organization and each model which composes a real-world disaster simulation. Those simulators are integrated using the HLA (High Level Architecture), a standard interface for a distributed simulation. A prototype of the core software based on this scheme is implemented. Then, we demonstrate and confirm the applicability and efficiency of this scheme by introducing the evaluation result.

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This paper aims to study how to gain the consistency of the state in a DVE(Distributed Virtual Environment) with lag, under the condition of P2P (peer-to-peer) protocol. That is, how to reduce the difference in time of the DVE state information between terminals caused by lag and how to control the shared object in real-time online game is studied. Specifically, the mutualprediction protocol is used in P2P type of the DVE. By utilizing this function, each terminal can compute mutually the state of the local avatar predicted by the remote terminals. In addition, we introduce a concept called AtoZ (Allocated Topographical Zone) of an avatar in which a shared object can be accessed and controlled preferentially by each avatar, dynamically changing its geometrical property depending on the relative arrangement among the object and avatars. As an example of the application using this function, a real-time network air hockey is implemented, in order to evaluate the influence on the real-time interactivity by the protocol above is performed.

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This paper discusses a conference state estimation method that uses only biosignal processing; linguistic understanding is avoided. In conventional dialogue communication research, the physiological characteristic of "entrainment" between the participants has been already reported. We extend "entrainment" to introduce the concept of "resonance" to grasp the relationship between attendees. We then propose a method which estimates the conference state from "resonance". First, using a multimedia conference system, we record conference data including time-series records of heart rate. By observing and analyzing the conference data, we assess the "resonance" phenomenon among the talkers. Using the "resonance correlation matrix", a newly proposed index based on the correlation of the heart rate data, conference participative state can be successfully estimated.

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Recently many citizens have wanted to publish and share information about their points of interest in the real cities and regions through WWW. Web-based virtual space, which is constructed as a digital copy of the real world, is useful for such purposes. Several systems have enabled users to submit their subjective information about real world and make indirect interactions each other. In this paper, we discuss one extension of such virtual spaces, which is realized by spatial deformation. Our proposed virtual space enables users to create group-based cognitive maps. We discuss our basic concepts in detail. And we also show our prototype system, experimental uses and its applications.

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Aiming at a rich and useful communication system in our future daily life at home, we propose a novel communication concept in which people can mutually share their intention and emotion through their spontaneous behavior. Since our new scheme "ComAdaptor" can adapt to and offset the differences in the structures of each room, we can create mutual real space sharing communication systems that allow users in remote locations to communicate as though they entered the other party's room in accordance with the room layout. In a simple experimental system, body motions were successfully adapted and transmitted between two structurally different rooms. The successful experiment confirmed the validity and high potential of the proposed concept.

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We have developed the multi-user communication platform called "PalmPlaza". This paper describes some problems of 3D virtual spaces and the PalmPlaza system which used various web technologies. And we experiment the contents creation easiness for public end-user and evaluate this system.

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This paper proposes a new haptic device to display the softness of elastic objects. The fingertip contact area and the reaction force were controlled simultaneously to display the fingertip sinking into soft materials. The contact area was controlled pneumatically by controlling the air pressure between the rubber membrane and the end-effecter of a force display. The psychophysical experiment clarified that the contact area spread in addition to the reaction force provides the more accurate softness sensation.

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Using virtual routes that were projected in CAVE having 5 screens, we examined memory of distances and orientations between a start point and a goal point. Subjects estimated only distances on linear routes, and both distances and orientations on curved routes. The moving distance, speed and density of surrounding objects affected the distance estimations and the only moving distance affected the orientation estimations. Especially, the interaction of distance estimation between moving distance and density of surrounding objects was characteristic result that there were overestimations in short distance with high object density. In addition, we examined the effect of having knowledge for a goal point from the beginnings of the trials, and showed that the knowledge affected the effect of density. We inferred two memory strategies by using static information and by using dynamic information to account for these data.

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