Transactions of the Virtual Reality Society of Japan
Online ISSN : 2423-9593
Print ISSN : 1344-011X
ISSN-L : 1344-011X
Volume 10 , Issue 2
Showing 1-20 articles out of 20 articles from the selected issue
  • Type: Cover
    2005 Volume 10 Issue 2 Pages Cover1-
    Published: June 30, 2005
    Released: February 01, 2017
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  • Type: Index
    2005 Volume 10 Issue 2 Pages Toc1-
    Published: June 30, 2005
    Released: February 01, 2017
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  • Hiroo Iwata, Masahiko Inami
    Type: Article
    2005 Volume 10 Issue 2 Pages 143-
    Published: June 30, 2005
    Released: February 01, 2017
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  • Jun Shimamura, Kenichi Arakawa
    Type: Article
    2005 Volume 10 Issue 2 Pages 145-153
    Published: June 30, 2005
    Released: February 01, 2017
    JOURNALS FREE ACCESS
    This paper describes a novel approach to the construction of a projector-based augmented reality environment. The approach is based on capturing the dynamic changes of surfaces and projecting the images within a large real environment using a system that includes a laser range finder and a projector, whose optical axes are integrated by mirrors. The proposed method offers two distinct advances: (1) robust 3-D viewpoint detection from consecutive range images, and (2) fast compensated image generation and presentation with view frustum clipping to measured surfaces. A prototype system is shown to confirm the feasibility of the method; it generates compensated images to suit the user's viewpoint that are then projected within dynamic real environment, in real-time.
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  • Yasuhiro Mukaigawa, Hirobumi Nagai, Yuichi Ohta
    Type: Article
    2005 Volume 10 Issue 2 Pages 155-162
    Published: June 30, 2005
    Released: February 01, 2017
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    We introduce SpaceRelighter, a projector-based mixed reality system that records illumination in a real scene and reproduces it at a later time by projecting a light pattern onto the scene. Users can see a virtually illuminated real scene without having to wear special devices such as a head-mounted display. Because the virtual illumination and real scene are merged in a real 3-D environment and not on a 2-D display, users have a better sense of reality. We first explain the principle of estimating light patterns by photometric and geometric conversions. We then describe an extended method for reducing the problem of occlusion by using multiple cameras and multiple projectors. We constructed a prototype system including two cameras and two projectors to confirm that illumination can be reproduced using projectors.
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  • Ryuho Hayashi, Fumitaka Nakaizumi, Hiroaki Yano, Hiroo Iwata
    Type: Article
    2005 Volume 10 Issue 2 Pages 163-171
    Published: June 30, 2005
    Released: February 01, 2017
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    We developed a spherical immersive projection display, a new model of EV(EnspheredVision). This display consists of spherical screen, plane mirror, convex mirror, six projectors and mechanical shutter. Multiple projector enables to improve the image resolution and brightness as compared with the former EV. Observer can watch the 360 degree panoramic stereo image using liquid crystal shutter glasses.
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  • Hitoshi Ban, Hideo Saito
    Type: Article
    2005 Volume 10 Issue 2 Pages 173-182
    Published: June 30, 2005
    Released: February 01, 2017
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    In this paper, we propose a vision-based method for hand written pattern input and display system that enable a user to input the pattern by handwriting with the white rectangle board on hand and to make it display on the white board utilizing a video projector and two cameras which are installed above the user. This system consists of two cameras and a video projector which are geometrically related by the weak calibration, and projects the handwriting operation result of the user on the white board and the move result of the handwritten pattern compared with movement of the white board. Because homography of the white board captured by both cameras and fundamental matrix between the projector and cameras are only used, distinction of handwriting operation and position at the time of handwriting pattern projection become possible with weak calibration of the camera and the projector, which is easily performed by simple operation. For demonstrating the validity of the proposed system, we show that the user can write pattern on a board with arbitrary pose and position, while the pattern is displayed on the board in real-time.
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  • Wataru Hashimoto, Kyouhei Yoshida
    Type: Article
    2005 Volume 10 Issue 2 Pages 183-189
    Published: June 30, 2005
    Released: February 01, 2017
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    Immersive display is the device that can provide an immersive viewing experience by surrounding around user. The typical problem of the display is that the device occupies huge space and it is hard to move the whole environment. This paper proposes an transportable immersive display. Our environment uses existing walls as screen. In order to avoid the focus problem when the projector image displays on non-planer surface, we utilizes a convex mirror to increase the length of the projector's focal depth. In addition, the mirror helps the projecter's image to spread the wide area. This paper also reports the distortion correction method of the projected image on the various shapes of the wall.
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  • Hideyuki Ando, Tomohiro Amemiya, Taro Maeda
    Type: Article
    2005 Volume 10 Issue 2 Pages 191-199
    Published: June 30, 2005
    Released: February 01, 2017
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    The Wearable Scanning Laser Projector (WSLP) is a novel head-mounted display for augmented reality (AR). WSLP specializes the movement of a narrow display area to a wide real environmental area. AR systems commonly uses optical see-through head-mounted displays (HMD). With such HMDs, because the images are projected at a specific focal length, it is difficult to observe both the object and the corresponding images at the same time when they exist at different depths. In the WSLP, the center of the mirrors scanning the laser beam can be aligned conjugate to the center of the wearer's eye. As a result, the light spot of the beam is always observed at any depth. With the WSLP, information can be shared with nearby friends and colleagues who are not wearing similar devices.
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  • Daisuke Kondo, Toshiyuki Goto, Makoto Kouno, Ryugo Kijima, Yuzo Takaha ...
    Type: Article
    2005 Volume 10 Issue 2 Pages 201-208
    Published: June 30, 2005
    Released: February 01, 2017
    JOURNALS FREE ACCESS
    Human anatomical models are often used by medical students to master the human body's structure. Medical students can learn the position, size and shape of complex inner organs exactly by handling and examining the parts of a human anatomical model. The purpose of this study is to construct a virtual anatomical model using a screen in the shape of a human figure on which images of inner organs are represented by projection, and can be handled directly by the user's hand and examined. For this purpose, a method so called as "Duality Rendering" is introduced to compensate the distortion when the image is projected on the arbitrary surface. The nature of this free-form projection display is examined in terms of the relation between the sensor error and the remaining amount of image distortion for pragmatic use in the anatomy education.
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  • Naoto Ono, Hiroaki Yano, Hiroo Iwata
    Type: Article
    2005 Volume 10 Issue 2 Pages 209-215
    Published: June 30, 2005
    Released: February 01, 2017
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    This paper describes image projection to the volumetric haptic display. The volumetric haptic display can represent a physical characteristic of 3-D virtual objects, such as shape and elasticity, as a real object in the real world. We try to project image around this 3-D object with using projector and create integrated environment that contains haptic information and visual sense, but there are two problems. One is distortion of the image on the screen, and the other is that the image has been projected on the user's hand during interaction. These problems destroy the feeling of unity in the haptic information and visual sense. To solve them, we approached distortion collection method using simulator and image extraction method using rotary mechanical shutter. Experimental result shows that these methods enable more natural projection.
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  • Takayuki Uchida, Tomohiro Yendo, Naoki Kawakami, Susumu Tachi
    Type: Article
    2005 Volume 10 Issue 2 Pages 217-220
    Published: June 30, 2005
    Released: February 01, 2017
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    The Retro-reflective Projection Technology, which projects a virtual object on the screen of retro-reflective material, is suggested as the method to fuse the real world and the virtual world visually. This method enables the screen to be considered as the metaphor of the virtual object and the virtual object to be operated intuitively by detecting the 3-dimensional coordinates of a screen. However the number and shape of screens are restrained in the conventional position detection techniques. We solved this problem by position measurement using the image recognition with the marker. Its marker is made of the material that is transparent for the visible light but absorbs the infrared light so that it doesn't spoil the function for screen.
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  • Daisuke Wakatsuki, Ikuo Ishii, Akira Takahashi
    Type: Article
    2005 Volume 10 Issue 2 Pages 221-229
    Published: June 30, 2005
    Released: February 01, 2017
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    This paper describes an object shape resolution control method in consideration of an allowable shape error caused by apparent movement in order to achieve an effective representation of a detailed object shape. The resolution is controlled by allowable contour error and allowable brightness error due to the movement of the appearance of the object independently in addition to traditional resolution control methods by static shape recognition characteristics of observers. The experiments with our method show better results in processing time for drawing, in physical quality of object images and in subjective quality evaluation in comparison with previous methods.
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  • Yoshio Suzuki, Yuriko Takeshima, Nobuaki Ohno, Koji Koyamada
    Type: Article
    2005 Volume 10 Issue 2 Pages 231-239
    Published: June 30, 2005
    Released: February 01, 2017
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    A volume rendering is widely used for intuitively understanding 3-dimensionaly distribution of physical quantities. When the quantities have a nest-like distribution, however, the inside distribution cannot be observed. As one of the solution, an immersive virtual reality (VR) system is useful, since the researcher can immersively observe the distribution by using such a system. However, a plane slice sampling method conventionally used in the volume rendering has a problem that the quality of visualized images deteriorates especially in the immersive VR system. To resolve the problem, a spherical surface sampling method is applied to the volume rendering in the immersive VR system. The quality of image and the display speed are compared between these two methods.
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  • Tetsuya Yokoyama, Toshio Yamada, Hideki Tanahashi, Haruhisa Kawasaki
    Type: Article
    2005 Volume 10 Issue 2 Pages 241-247
    Published: June 30, 2005
    Released: February 01, 2017
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    We propose a new method that is enable to deform a soft object with Finite Element Method in real-time processing. The proposed method has a feature that the object is constraint in a contact point. When the contact point is changed, the inverse matrix of the rigid one is also changed. Since the calculation amount of the inverse matrix is O(n^3), the real-time processing is impossible. In the proposed technique, the calculation amount is reduced to O(n). So in the experiments, we checked its usefulness.
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  • Hiroaki Shigemasu, Takao Sato
    Type: Article
    2005 Volume 10 Issue 2 Pages 249-256
    Published: June 30, 2005
    Released: February 01, 2017
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    Objects and people in stereograms typically appear flat as if they were cardboard cut-outs. This is still true when the angular size of objects in the stereograms is the same as those of original scene. Howard and Rogers (1995) suggested that the phenomenon occurs because stereo pictures are viewed at a much shorter distance than the original scene. We investigated this phenomenon in relation to this scaling problem and the results showed that although it causes a significant depth reduction, the scaling from viewing distance does not fully explain the phenomenon. However, when the disparity between object and background were added, the object appeared flatter. These results suggest a new aspect for the explanation of cardboard cut-out phenomenon.
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  • Toshiyuki Kimura, Kazuhiko Kakehi, Kazuya Takeda, Fumitada Itakura
    Type: Article
    2005 Volume 10 Issue 2 Pages 257-266
    Published: June 30, 2005
    Released: February 01, 2017
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    It is important to evaluate the effect of the number of channel signals in the sound field auralization system based on wave field synthesis. Although the effect of the number of channel signals on the physical accuracy of wave fronts was investigated, the effect of the number of channel signals on sound field perception was not evaluated. In this paper, two subjective assessments were performed for evaluating the effect of the number of channel signals on directional perception and spatial impression. The results of the two subjective assessments showed that there was no perceptual difference of the directional perception and spatial impression even if the wave fronts were reproduced in the very low frequency range.
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  • Type: Appendix
    2005 Volume 10 Issue 2 Pages 267-269
    Published: June 30, 2005
    Released: February 01, 2017
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  • Type: Appendix
    2005 Volume 10 Issue 2 Pages App1-
    Published: June 30, 2005
    Released: February 01, 2017
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  • Type: Cover
    2005 Volume 10 Issue 2 Pages Cover2-
    Published: June 30, 2005
    Released: February 01, 2017
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