Journal of the Robotics Society of Japan
Online ISSN : 1884-7145
Print ISSN : 0289-1824
ISSN-L : 0289-1824
Volume 39, Issue 1
Displaying 1-16 of 16 articles from this issue
On special issue
Innovative Technology
  • Tomoya Noake, Ryuji Kitamura, Saikhanbayar Uuganbayar, Hiroki Igarashi ...
    2021 Volume 39 Issue 1 Pages 71-77
    Published: 2021
    Released on J-STAGE: January 25, 2021

    We have developed a basic experimental device to assess the harm caused by a small UAV propeller and evaluate the performance of personal protective equipments required when the propeller comes into contact with the human body. By using the device, the collision experiments between small UAV propellers and the object that imitates the human body were carried out. According to the experiments with 15 inch propellers, though it is confrimed that the existing blade-registance gloves on EN388 reduce the harm of the collision, it is also demonstrated the highest blade-registance level of 5 in EN388 is not enough for the propeller collision protection. These experimental results indicate the need of further development of the personal protective equipments for UAV safety.

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  • Kouki Senoo, Tadashi Egami
    2021 Volume 39 Issue 1 Pages 78-86
    Published: 2021
    Released on J-STAGE: January 25, 2021

    We describe the development and control of an inverted-pendulum electric wheelchair that moves forward and backward and rotates according to changes in the user's center of gravity, without using hands. To rotate a conventional inverted-pendulum electric wheelchair, the user must manipulate a control handle. In the developed wheelchair, we removed the front auxiliary wheels from a conventional electric wheelchair and moved the main wheel axis to the chair's center of gravity. The wheelchair is propelled forward and backward by means of an accelerometer that monitors shifts in the user's center of gravity. Left–right rotation is controlled according to differences in air pressure between the right and left sides of an air cushion placed on the seat surface. Stable mobility that is independent of the user's weight is achieved by incorporating a robust control system that utilizes a disturbance observer. We also propose a method for preventing bias travel that achieves the same operability as running on a horizontal surface by changing the dead zone for right–left differences in air pressure.

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  • Takehiro Tsuruta, Mikita Miyaguchi, Ataru Fujii
    2021 Volume 39 Issue 1 Pages 87-97
    Published: 2021
    Released on J-STAGE: January 25, 2021

    We have developed fully automated mobile marking robot system. Until now there are no report about productivity using marking robot system at construction site in previous research. In this paper we proposed a highly efficient work planning method for improving efficiency for marking robot. Minimizing time required for moving all the marking positions leads to improvement of the work efficiency. Marking robot must move to all the marking positions and draw lines according to floor layout plan. First, we developed a method to reduce the number of moves by clustering several lines. Minimizing the time for moving all the marking positions is similar to traveling salesman problem (TSP). Second, we proposed the method to search the optimized moving path by solving the TSP taking into account the moving method of the marking robot. Finally we implemented proposed method to marking robot system and used it at construction site. We found that proposed method 24% improved working time than that without it.

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