Abstract-In this paper, we propose a novel and coherent framework for fast footstep planning for legged robots on a flat ground with 3D obstacle avoidance. We use swept volume approximations computed offline in order to considerably reduce the time spent in collision checking during the online planning phase, in which an RRT variant is used to find collision-free sequences of half-steps (produced by a specific walking pattern generator). Then, an original homotopy is used to smooth the sequences into natural motions avoiding gently the obstacles. The results are experimentally validated on the robot HRP-2.

Abstract-In this paper, we illustrate experimentally an original real-time replanning scheme and architecture for humanoid robot reactive walking. Based on a dense set of actions, our approach uses a large panel of the humanoid robot capabilities and is particularly well suited for 3D collision avoidance. Indeed A-* approaches becomes difficult in such situation, thus the method demonstrated here relies on RRT. Combined with an approximation of the volume swept by the robot legs while walking, our method is able to cope with 3D obstacles while maintaining real-time computation. We experimentally validate our approach on the robot HRP-2.