Footstep planning for tripod gait in obstacle environment

The footstep planning for the hexapod robot in obstacle environment is proposed in this paper. The tripod gate is employed as the basic gate so that the footstep planning problem becomes the combinational problem of stepping one by one like a bipedal robot gate. The triangle shape can represent the tripod and its motion and its apexes indicate the footstep pattern and the landing position of the foot. A* algorithm solves the combination problem with cost function which consist of the number of stepping, the length from the goal, and the penalty of approaching obstacles and more unstable gait. Experiment with an actual robot shows the appropriate footstep in the obstacle environment.