Transactions of the Virtual Reality Society of Japan
Online ISSN : 2423-9593
Print ISSN : 1344-011X
ISSN-L : 1344-011X
Volume 22 , Issue 4
Showing 1-13 articles out of 13 articles from the selected issue
  • Sho Tatsuno, Tomohiko Hayakawa, Masatoshi Ishikawa
    2017 Volume 22 Issue 4 Pages 447-455
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    A supporting training system using a haptic device is considered to contribute more to motion learning than other stimuli that stimulate the human somatosensory system. However, the apparatus required for haptic stimulation is large, although the output is small. Electrical stimulation has been gaining attention in the field of human interfaces in recent years as a potential solution to this problem. Electrical stimulation is superior to existing haptic interfaces in that a large output can be generated using a few batteries, which can drive muscles to contract. Therefore, in this study, we developed a training system using electrical stimulation. This system teaches the amount of the rotation of arms, which is difficult to achieve by means of other haptic stimuli. We confirmed that the form in the rotation direction was successfully modified by using this system. The form was improved by 32% through electrical stimulation during training, and the form correction was achieved via the somatosensory system, which is difficult with the existing method. In addition, we verified that the skill was memorized in a short period of time and retained in the short term.

    Download PDF (14525K)
  • Hiroo Iwata, Yu-ta Kimura, Yuki Enzaki, Hiroaki Yano
    2017 Volume 22 Issue 4 Pages 457-465
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    The “Big Robot” has two legs with wheels, mounting the pilot at 5m height position. The robot goes forward according with the motion of the feet of the pilot. It is programed to make trajectory of head position of 5m giant. Thus, the pilot feels as if his/her body were extended to 5m giant. The biggest technical issue in large-scale robot is falling down to the ground. Thus, the base frame of BigRobot is made of steel and its linkages are made of CFRP. This structure enables low center of gravity and prevents from falling down. The Big Robot was exhibited at Ars Electronica Festival 2015, Tsukuba Media Art Festival 2015 and Emerging Technologies of SIGGRAPH 2016, that proved its effectiveness.

    Download PDF (7262K)
  • Kosuke Sato, Masahiro Ueda, Keita Watanabe, Shuichi Mizuno, Masayoshi ...
    2017 Volume 22 Issue 4 Pages 467-476
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    This paper presents a system that consists of three robots to imitate the motion of top volleyball blockers. In a volleyball match, in order to score by spiking, it is essential to improve the hitting percentage of each spiker. To increase the hitting percentage, iterative spiking training with actual blockers is required. Therefore, in this study, a block machine system was developed that can be continuously used in an actual practice field to improve attack practice. This robot performs high speed movement on 9 m rails that are arranged in parallel with the volleyball net. In addition, an application with a graphical user interface to enable a coach to manipulate these robots was developed. It enables the coach to control block motions and change the parameters such as the robots' positions and operation timing. Through practical use in the practice field, the effectiveness of this system was confirmed. In this paper, we describe the effectiveness to players through utilization of the system in actual practice. In addition, we clarify the improvement points exposed at that time, propose and construct a sensor system and describe its evaluation and future possibilities.

    Download PDF (32640K)
  • Takashi Kikuchi, Katsutoshi Masai, Maki Sugimoto, Bruce H. Thomas, Yut ...
    2017 Volume 22 Issue 4 Pages 477-483
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    In this paper, we propose EarTouch, a new sensing technology for ear-based input for controlling applications by slightly pulling the ear and detecting the deformation by an enhanced earphone device. It is envisioned that EarTouch will enable control of applications such as music players, navigation systems, and calendars as an “eyes-free” interface. As for the operation of EarTouch, the shape deformation of the ear is measured by optical sensors. Deformation of the skin caused by touching the ear with the fingers is recognized by attaching optical sensors to the earphone and measuring the distance from the earphone to the skin inside the ear. EarTouch supports recognition of multiple gestures by applying a support vector machine (SVM). EarTouch was validated through a set of user studies.

    Download PDF (2171K)
  • Masakazu Nakazawa, Hideki Koike
    2017 Volume 22 Issue 4 Pages 485-491
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    In this paper, we proposed a method to fix the point of views (POVs) of equirectangular format videos, which is captured by omnidirectional cameras embedded in a ball, to an arbitral direction even if the ball is rotating. Feature points are extracted from an entire omnidirectional image and the camera's pose is estimated by feature matching and the 5-point algorithm. The POV of the current frame is modified to the one of the initial frame by applying the product of estimated rotation matrices between all of adjacent frames up to the current. The proposed method is not limited to our ball prototypes and can be applied to any omnidirectional videos taken with different camera systems.

    Download PDF (11247K)
  • Yuji Sano, Koya Sato, Ryoichiro Shiraishi, Mai Otsuki
    2017 Volume 22 Issue 4 Pages 493-502
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    We focused on the effect that applying visual and haptic stimuli reduce the task load of situation awareness during a ball game, and we hypothesized that as a result, they also reduce the number of misplays. We developed the system which can provide the visual and haptic stimuli for supporting 3-on-3 soccer game in real-time; for visual stimuli, the position relationship of opponent players are shown, and for haptic stimuli, the position of opponent player who are in the out of view angle. Through the experiment we evaluated whether the visual and haptic stimuli can reduce the task load in a ball game. As a result, the proposed visual or haptic stimuli itself reduced the player's task load and improved the ball handling skill. On the other hand, we found that the combination of visual and haptic stimuli did not reduce the task load of player, and did not contribute to the reduction of misplay.

    Download PDF (16803K)
  • -How VR Changed The Hang Glider and Paraglider Popularization Activity-
    Takuya Nakayama, Yuji Suzuki, Takako Yoshida
    2017 Volume 22 Issue 4 Pages 503-512
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    Although the hang glider is well known, few people have experienced it since one has to drive to suburban flight areas to try it. Nowadays, conventional flight exhibitions that include towing enable beginners to drop in at flight experience events in urban open spaces, including central Tokyo. To boost this urban exhibition, we designed an indoor hang glider virtual reality system that is easy, stable, and offers some of the most exciting flight experiences that hang gliders can ever have, regardless of the weather conditions. This system enabled to propagate the fascination with the hang glider for many people at the event even in urban Tokyo.

    Download PDF (3385K)
  • Akimi Oyanagi, Ren Ohmura
    2017 Volume 22 Issue 4 Pages 513-522
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    Since body ownership illusion is expected to enhance an individual ability and positive psychological effect, any existing studies investigated the cause of the body ownership illusion on a human-like avatar. However, few studies have been focused on an avatar whose figure is a non-humanlike, such as a bird. If the illusion on a bird avatar can be controlled, the user's feeling of the presence in virtual reality world and flying experience are expected to be enhanced. Thus, we conducted some experiments to investigate factors to elicit a sense of body ownership over a bird avatar. We evaluated how features of a bird, such as flying action, short body, and sounds of flapping, affected the sense of body ownership. Our findings suggest that a motion synchronization between a participant's body and an avatars' one induce a sense of body ownership. Furthermore, appearance of a bird increases user's immersion in flying experience. Avatar's appearance affects a sense of body ownership over a non-humanlike avatar.

    Download PDF (2807K)
  • Fumihiko Nakamura, Katsuhiro Suzuki, Katsutoshi Masai, Yuta Itoh, Yuta ...
    2017 Volume 22 Issue 4 Pages 523-534
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    Facial occlusions caused by HMD (Head-Mounted Display) make capturing user's face hard. In this paper, we propose a technique to classify the mouth shapes into 6 classes using optical sensors embedded in HMD and give labels to training dataset by vowel recognition. We conducted an experiment with 5 subjects to compare recognition rates of machine learning in manual labeling and automated labeling conditions. The result shows that proposed method achieved an average of 99.9% classification accuracy in the manual labeling condition, and of 96.3% classification accuracy in the automated labeling condition.

    Download PDF (5229K)
  • Takahiro Uji, Yiting Zhang, Hiromasa Oku
    2017 Volume 22 Issue 4 Pages 535-543
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    Retroreflectors can reflect incident light to the light source, and they are often used as the optical marker for machine vision. Most of the conventional retroreflectors are made from glass or plastic, and they are not edible. Thus, it is difficult to apply them to foods or inner wall of digestive organs. This paper proposes edible retroreflector made from foodstuffs. A recipe of the edible retroreflector using kanten, which is traditional Japanese cooking ingredient to form a transparent jelly, is described. A prototype made from kanten showed retroreflective function from reflectance measurement experiment. Dynamic projection mapping on a Swiss roll was successfully demonstrated using the prototype as an optical marker.

    Download PDF (44207K)
  • Takuma Miwa, Hirohiko Kaneko
    2017 Volume 22 Issue 4 Pages 545-552
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    In this study, we investigated the effects of gravity direction on the perception of motion in depth. We measured the magnitude of the acceleration of approaching and receding object that appeared to move with a constant velocity using the method of constant stimuli. To manipulate gravity direction from the vestibular and somatosensory systems, we used three conditions of observer's body orientation: upright, supine, and prone states. The results showed that the deceleration of the approaching motion was greater when observed with the prone and supine states than with the upright state. Moreover, the greatest acceleration of the receding motion for perceiving constant velocity was the prone state, followed in order by the upright state and the prone state. We discuss the effects of risk by the moving object and of gravity direction in normal environment on the perception of moving object.

    Download PDF (2886K)
  • Takeharu Seno, Takaya Shimizu
    2017 Volume 22 Issue 4 Pages 553-556
    Published: 2017
    Released: December 31, 2017
    JOURNALS FREE ACCESS

    We examined whether vection strength could be modulated by the difference in the conditions of observing eyes, i.e. monocular or binocular observations and also, dominant eye or non-dominant eye observations. The eyepatch was used for making the monocular observation. The dominant eye was determined using the Miles Method. Eleven naïve volunteers and the second author participated in this experiment. Three vection measures (latency, duration and magnitude) were obtained. Obtained vection latency was significantly longer in the non-dominant-eye observing condition, although there were no significant differences in vection duration and magnitude. We can conclude that vection can be affected by the conditions of observing eyes.

    Download PDF (838K)
feedback
Top