考虑足地作用的足式机器人环境表征与路径规划

During the walking of a legged robot, the interactions between its end of feet and the terrain strongly affect the traversability of the robot. Foot-terrain interaction is closely related to the geometry of the terrain surface and the physical characteristics of it. Therefore, path planning based on geometric map alone is difficult to meet the demand of avoiding non-geometric hazards such as soft sand in the wild. To solve this problem, an environment model including geometric and physical characteristics is proposed in consideration of foot-terrain interaction for path planning of legged robots. By simplifying and unifying the foot-terrain interaction model under soft and rigid terrain, parameterized indexes characterizing the normal softness and tangential friction characteristics of the terrain are proposed, and a more comprehensive environment model is constructed by combining geometric characteristics and the proposed physical characteristics. Comprehensively considering the ground geometric and physical characteristics affecting the robot's traversability, the optimization target of path planning is reconstructed and the optimal path is planned for legged robots with graph search algorithm. Simulation and experiments with the hexapod robot Elspider verified that the proposed method can effectively avoid non-geometric hazards and plan a safer and more reliable path to traverse.