Development of Quadruped Walking Robots and Their Gait Study
Hironori Adachi*, Noriho Koyachi*, Tatsuya Nakamura**
and Eiji Nakano***
*Mechanical Engineering Laboratory, 1-2 Narniki, Tsukuba, Ibaraki, 305 Japan
** Faculty of Engineering, Mie University, 1515 Kamihama, Tsu, Mie, 514 Japan
*** Graduate School of Information Science, Tohoku University, Aramaki Aza Aoba, Aoba-ku, Sendai, 980 Japan
This paper describes the quadruped walking robots developed at the Mechanical Engineering Laboratory and their gait analysis. Legged locomotion has the potential to adapt itself to changes in walking conditions, but also has problems such as complexity. To overcome these problems, a new link mechanism called ASTBALLEM is used for the legs of the robots, and highly rigid and easily controllable legs are constructed by using this mechanism. To make a legged robot walk stably, it is necessary to provide a suitable gait. In this paper, two kinds of gaits are considered. One is the periodic gait, and it is systematically classified by two parameters. By using this classification method, suitable gaits for static walking and dynamic walking are selected. The other is the adaptive gait. In order to realize their potentials, walking robots must sense the walking conditions and change their gaits. Two adaptive gait schemes are proposed in this paper. One is a gait which adapts to the position of the center of gravity, and the other is a gait for incline terrain. Both gaits use force sensor data for detecting changes in the walking conditions. All the gaits discussed in this paper are experimentally evaluated.