This paper proposes a virtual chopsticks system using force feedback and object deformation with FEM (finite element model). The force feedback model is established by using a leverage based on the correct chopsticks handling mannar, and the force is applied to the index and middle finger. The object deformation is obtained in real-time by calculating inverse stiffness matrix beforehand.

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This paper describes design of a surface type haptic interface for presentation of hardness distribution in an elastic object. The haptic interface is composed of an elastic plate and a linear actuator array. It provides a spatially continuous surface on which users can effectively touch virtual objects using any part of their bare hand. The elastic plate is made of rubber and sponge. When the actuator pushes the plate, its hardness increases. The user feels as if hard object is submerged in a soft object. We analyze the performance of the device through measurements of rigidity and psychophysical tests.

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This paper proposes a new framework of a 3D workspace in which the "desk-top" of the personal computer (PC) and the real workspace are visually integrated together so that the user can refer and edit both digital and physical information seamlessly. Utilizing the mobility of the combination of wearable PC and head mounted display (HMD), PCs can be useful platforms for the office work. Employing a stereo pair of cameras installed on HMD, PC captures not only what the user sees but also 3D depth information in front of the user. Proposed system allows the user to handle virtual objects including web browsers, digital documents, images, 3D CG models in the same space with his/her own hand in intuitive manners without shifting the hand back and forth between a pen and a mouse.

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We propose a new method to display grasping and resultant force for multi finger object manipulation. In the method we eliminate the effect of the resultant force in the distances between fingers. We made an experiment to compare between conventional and proposed method.

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In human-scale virtual reality environment or augmented reality environment, force feedback plays important roll, as well as visual feedback. In such situation, force display requires large working volume and the ability to move easily. To satisfy these requirements , we've developed a non-grounded force display using gyro-moment effect. We measured various characteristics ,such as the threshold, the differential threshold. And we propose some techniques to indicate the information of territories or direction by using the force display. The effectiveness of this force display tested through some experiments and two applications.

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In this paper, we propose handy haptic devices which allow users seem-less manipulating multimedia data in an extended information environment. They are designed with the shape of every day tools, such as scissors, tweezers and syringe, which shapes denote their functional uses as proper affordances. In addition, the devices have haptic and thermo- feedback functions which display the quantity and freshness of information. We develop two types of handy haptic devices; a syringe device and tweezers device. Also, we realize extended information environments where users are able to access computerdata by those haptic devices without any conventional input devices; text editor among networked computers and sound control with a metaphor of liquid. The results of subject evaluations show that the proposed handy devices were easy to understand how to use and the notations of their haptic and thermo- feedbacks without any explanations in advance.

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The aim of this paper is to examine how the humans perceive the object weight related to size-weight link. A size-weight illusion was used to investigate the role of visual and haptic cues in producing of adapted force during holding objects. Flanagan et. al. reported that the size weight illusion is caused by independence of perceptual and sensorimotor predictions in the current paper. We used a string-based haptic interface 'SPIDAR' to build the size-weight illusion environments and measured the hand displacement as a parameter to represent the subject's expected weight during holding task. As a result, we found that the size-weight illusion disappeared when the differences between the peak values of the dropped hand positions of two objects vanished. This results indicates that this phenomenon comes from the mismatch between the expected weight and actual sensory feedback related to object weight.

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We have developed an eye pointer applicable in an immersive projection display, using gaze-tracking as an interface sensor. The eye pointer can make a pointing of virtual objects without hand's use in a 3D virtual space. The circular polarization stereoscopic vision enables us to use a gaze tracker in an immersive projection display. The eye pointer uses speed feature in eye movements, but has delay due to filtering process for a stable pointing. To evaluate the pointing performance, we made experiments to point at moving virtual objects, comparing the eye pointer with a joystick and a magnet stick pointer. The experimental result indicates the pointing of the eye pointer is quicker than that of the joystick, but inferior to that of the magnet stick, and the questionnaire result suggests that the eye pointer does not always give us good impression in terms of response instead of the quick pointing.

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This paper describes a method to extend the registration range ofa visionbased augmented reality (AR) system. We propose to use natural feature points contained in images captured by a pair of stereo cameras in conjunction with pre-defined fixed fiducial markers. The system also incorporates an inertial sensor to achieve a robust registration method which can handle user's fast head rotation and movement. The system first uses pre-defined fiducial markers to estimate a projection matrix between real and virtual world coordinate systems. At the same time, the system picks up and tracks a set of natural feature points from the initial image. As a user moves around in an AR environment, the initial markers fall out from the camera frame and natural features are then used to recover the projection matrix. Experiments for evaluating the feasibility of the proposed method are carried out and show the potential benefits of the method.

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In this paper, we describe an approach to generating the tetrahedral mesh model from the CT data for the purpose of haptic representation of the volume data by the spatial constraint based haptic rendering algorithm. In the approach we propose the idea of adaptive mesh generation to reduce the memory space consumption. Also, we introduced the idea of conditional node merging to obtain the model that is topologically more suitable for the haptic rendering. We quantitatively evaluated the performance of our approach; the adaptive mesh generation method reduced the memory consumption of the process to 1/2-1/9, and the conditional node merging had considerable merit in deducing the run-time computation time of the haptic rendering.

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Pyrotechnicians must determine many factors such as timing, music, and places in the production of a fireworks show. However it is difficult to work efficiently because the results of production can not be visually confirmed with ease in a real environment due to the cost and danger. This paper proposes a fireworks production support system that realizes an efficient work for fireworks production. In the proposed system, a user inputs information about fireworks types, launch positions and timing, and music. The fireworks show is simulated in real time by using input information, and is visualized in a panorama viewer and on an HMD (Head Mounted Display). The fireworks show can be produced efficiently with the low cost by using this system. The proposed system has been successfully demonstrated and evaluated by pyrotechnicians to show the validity of thesystem.

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The resent developments of the compact hardware have been realizing Wearable Computers. On the other hand, there are just a few studies of the input interface for wearable computers. However, most of those interfaces lack portability or are not comfortable in using it. This paper presents "Hand-Menu System", an innovative input interface for wearable computers, utilizing Augmented Reality techniques. This system gives the user a truly intuitive non-contact input interface with visual feedback and physical senses. This system lets a user to choose one of menu items superimposed on his five fingertips of a hand by simply touching it with a fingertip of the other hand.

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We intend to provide an engaging and exciting experience that demonstrates new force feedback technology for advanced VR applications. Our proposed force-feedback system(SPIDAR-G) will allow users to interact with virtual objects naturally by manipulating a grip located in the center of the device frame. In this paper, we explain a haptic device with 7 degrees of freedom (DOF) which can input translation, orientation and grasp measuring and reflect force by using the tension of 8 strings. We suggest the method to calculate translation, orientation and grasp and the method to display reflect force with 7 DOF. Finally, we refer the characteristic of this device.

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This paper gives a method to achieve haptic reproduction and real-time visualization of a beating heart for cardiac surgery simulation. The authors focus on time series dataset and produce a new framework for interactive feedback of active tissues. The framework provides both detection and response of collisions between a manipulator and a virtual heart. Physically based haptic feedback of cardiac motion is also simulated using a stress-pressure model, which is adapted to elastic objects filled with fluid. Time series datasets of a normal volunteer were applied to a simulation system with a force feedback device using real-time volume rendering. Finally, results of visual and haptic feedback and medical assessment show the achieved quality and performance of the developed system.

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