Adaptive Gait for Large Rough Terrain of a Leg-Wheel Robot (Fourth Report: Step-Over Gait)
Shuro Nakajima and Eiji Nakano
The Department of Advanced Robotics, Chiba Institute of Technology
2-17-1 Tsudanuma, Narashino, Chiba 275-0016, Japan
A leg-wheel robot has mechanically separated four legs and two wheels, and it performs high mobility and stability on rough terrains. The adaptive gait for large rough terrains of the leg-wheel robot is composed of three gait strategies. In this paper, the step-over gait, which is one part of the adaptive gait, is described. The proposed method is evaluated by simulations and experiments. The point of the flow of the step-over gait is described. When the body reaches an obstacle, it does not come to advance easily. In this case, the robot can not always understand the height of the obstacle, since its forefeet sometimes do not touch it. Therefore, the robot raises its body as possible as it can, and gets over the obstacle. After getting over it, the body is lowered until it touches the ground. The system judges whether the body touches the ground by the information on load sharing ratio of legs.
This paper is the full translation from the transactions of JSME Vol.72, No.721.
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