Dental calculus, hardened plaque on the teeth, is a cause of periodontitis, or gum diseases in mouth. For dentists and dental hygienists, it is an important task to remove the calculi of patients. The task is called "tooth scaling" and the calculi just beside the gum and between the tooth and gum are always removed away by using a hand scaler. Since the scaling by a hand scaler requires skill, apprentice dentists and dental hygienists must be trained to get the skill. Unfortunately in the training environment, however, there are several problems such as difficulty in collecting teeth on which various type calculi are stuck, lack of cooperative patients, and so on. Then, the authors have been newly developed a simulator for the training by using a PHANToM and a video-see-through HMD. The training effectiveness has been evaluated by artificial calculus removal on model teeth. The experimental result shows the developed simulator is more effective than the conventional paint removing method.

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This paper deals with a remote instruction system by which an instructor trains a learner how to draw pictures or figures while conveying the sense of force through a network. In the system, we introduce media synchronization control with prediction as Quality of Service (QoS) control and examine the influences of network delay, delay jitter and packet loss on the quality of haptic media synchronization by subjective assessment. As a result, we show the effectiveness of the Virtual-Time Rendering (VTR) media synchronization algorithm with prediction. We also demonstrate that the Mean Opinion Score (MOS) value at the instructor's terminal is smaller than that at the learner's terminal. Furthermore, we show that the MOS value can be estimated with high accuracy from the summation of the network delay from an instructor's terminal to a learner's terminal and that in the opposite direction.

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This paper describes development of a bobsleigh ride simulator. It is expected to be used for training in the off-season. Virtual bobsleigh riding is realized by simulating a real course in Nagano City. High-speed gliding motion is generated by dynamic physical simulation under the condition of surface constraint. Scene images are projected onto a surround screen constructed of four large-screens. The motionbase system is controlled by six electric-motorized axes according to the result of gliding motion in realtime. A method for enhancing insufficient motion-feedback force is also presented for increasing real feeling.

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This paper proposes the safety-education VR contents to make subjects experience the state of cognition that causes accident easily. On the working environment, the accident is often caused by the failure of operation that is called as human error. One of the cause of these error is inappropriate attention management. The ability to manage a cognitive resource is called the metacognition, and the improvement of this ability is effective in prevention of accidents. For the improvement of the metacognition ability, it is important not only knowledge of accidents but also the reflection of state of cognition when the accident happens. We propose to use the illusion of body image that was caused by cross modality stimulation for experience of accidents. It is thought that approach to dangerous part can be reproduced by control of body image using that illusion. We examined the method of presenting cross modality stimulation for control of body image to develop the safety-education VR contents.

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Recent years there are many haptic devices in the world, though few working environments are archived. This is because the difficulty of composing these working environment. Examples of the difficulties are the target modeling, physical modeling and graphics creation based on modification of an object, etc. Then we propose a haptic recording and reproducing system for training that uses a very simple algorithm called "Haptic Video." We use a visual camera, force sensor, impedance-based environmental reproducing algorithm and a trajectory displaying method. By using this system the operator has to do all is to operate his ordinal operation. In reproducing phase the displaying information are calculated from recorded one and the operator can feel the environmental visual and haptic information as it is and can train himself about the recorded handwork skills.

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Virtual reality training systems focusing on practical use in industries have been developed. The systems are originally intended to cover premature as well as mature workers. For the purpose, these include human error inducing and scenario-based functions. The validity of the developed systems are investigated based the questionnaire completed by the practical engineers and the error rate analysis after experimental execution of systems. In addition, cerebral activity during virtual reality training system was preliminary measured using a near infrared spectroscopy imaging to discuss the validity in deep.

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As to a pedestrian with Global Positioning System, it has been hard to steadily acquire his bearing just using GPS. In this paper, a novel practical method is proposed to acquire his azimuth instantaneously with a new wearable user segment of GPS even in his stillness. This is able to be used as an ideal input for the position and the orientation of the user. A novel educational system is also proposed using this device. It assists a student who focuses on a certain azimuth range in his stillness, supposing his focus is on the constellations at the bearing in the sky, by inquiring him whether he would like to have educational stories including Greek Myths, history of sciences related to the constellations on his focus.

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In conventional medical education, residents train their skills via clinical experiences (OJT). Virtual reality (VR) based training simulator comes under the spotlight as a powerful tool to solve the problem. Exclusion is a surgical manipulation of pushing aside organ to make a hidden tissue visible or enlarge work space. Improper manipulation causes fatal damage. This study aims to develop VR based exclusion training simulator. Multiple-finger interaction method with an elastic object is developed and glove-type multi-finger haptic device is integrated to the system. The prototype equips interactive visualization of stress distribution under exclusion. The system enables real-time calculation of deformation, reaction force and stress. The result of trial training suggested that the display of stress distribution enable effective training. Subjective evaluation by medical doctors proved the effectiveness of the system for exclusion simulator.

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To become a surgeon, theoretical knowledge has to be combined with practice through extensive experience in variations of the text-book case. A number of simulators have been developed for surgical training over the past decade. This paper describes an approach based on recorded surgical simulation and its playback as Annotated Simulation Records (ASR). Process for making and using ASRs in training consists of recording and editing of recorded manipulation, annotation of success factors of the manipulation and finally replaying the ASR with visualized success factors. The ASR-based approach promotes surgical education by reducing constraints of time, space and number of people involved, as well as by offering the possibility of flexible learning strategies and integrated assessment of surgical skills. The ASRs are demonstrated in the case of force exertion, which is a fundamental part of surgical manipulation and nowadays modelled in simulators with haptic feedback. Visualization of force exertion can present future, present and past states of the example interaction, and present and past states of the user's interaction.

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The purpose of this paper is to elucidate the basic data for future study as estimated from the demonstration class. At first, we conducted a "needs based investigation" for teachers to examine the VR teaching materials available for educational purposes. The investigation contents dealt with "use of materials," "level of students to be taught" and "functional needs of the VR materials". We have made improvements in the portability and operability of the 3D VR system used for screen presentations based on the results of the "needs investigation." Following this, we brought the VR teaching materials, which we produced, to a senior high school and performed a teaching demonstration using the VR system. Furthermore, we performed a survey based on the subjective evaluations of both teachers and students who attended the demonstration. As a result, the VR teaching material we used left a positive impression on the students and teachers who were involved in our demonstration.

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We have proposed a novel translational force perception method for mobile and wearable displays. The method exploits the nonlinear relationship between perceived acceleration and physical acceleration to generate a force sensation. A prototype of the haptic display based on the method generates unidirectional force sensation using a crank-slider mechanism that physically generates bi-directional force. Two experiments were performed to clarify the perceptual characteristics when human held the force display in the air. The results indicate that the angular resolution with perceived force direction was significantly smaller with the force display that counteracted a swinging force generated by motion of linkages than with one that doubled it. In addition, the frequency, at which the force sensation was effectively induced when human held the display in the air, shift slightly lower than that when human held the display fixated on a linear slider. Our knowledge would be a criterion for designing smaller and lighter nongrounding force displays.

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Two haptic displays for virtual reality have recently been developed: one is an earth-grounded type, and the other a body-grounded type. There is now a great deal of research in this field, including work on a body-grounded type of device, a GyroCube, a moment-type display using a mechanical brake and a force display using a gyro moment. We have developed another kind of moment-type force display using a half-toroidal CVT (continuously variable transmission). In this paper, we report improvement the display weight and investigation of two dimensional display. And the human perception ability of direction has been confirmed by experiment.

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The Wearable Active Camera/Laser-Pointer (WACL) is a body-worn tool equipped with a camera/laser head capable of pan/tilt control to assist field workers in remote collaboration. A remote expert can freely observe the real workplace and directly point at targets with a laser spot. In our previous studies, however, it was found that advanced visual assist such as line drawings on images can support remote collaboration more adequately than a laser spot if the instructstor needs to explain in detail. In this paper we first compared two wearable displays, a Head-Mounted Display (HMD) and Chest-Worn Display (CWD), to explore which one is more suitable for providing workers wearing the WACL with the additional visual assist. Next we examined how effectively the laser spot of the WACL link the real world to the advanced visual assist on the HMD or CWD. Results show that the CWD is superior in preference to HMD and the combination of the laser spot and wearable display can enhance task performance and usability.

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This paper presents a novel projection-based mixed reality (MR) system for visually enhancing the temperature distribution of user's body and his/her immediate environment by projection of a thermal image of the scene. Users of this system, which we call ThermoReality, can intuitively understand the heat phenomena on real objects, since the temperature distributions are seamlessly exposed onto them. The authors aim to exhibit the proposed system in a kind of science museum and open it up to the public. In this exhibition, visitors enjoy learning about the heat phenomena in their activity spaces. The heat phenomena which are visualized in the system can surprise visitors since such phenomena cannot be imagined in their daily lives. The authors believe that the system would be a trigger for visitors to get interested in the heat phenomena and understand them in more scientific detail.

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