Load Distributed Whole-body Motion Generation Method for Humanoids by Minimizing Average Joint Torque Ratio

In this paper, we propose a load distributed whole-body motion generation method for a humanoid robot whose limbs are constrained to environments. To minimize a load over the posture sequence, rst, we optimize each key frame posture by searching neighboring postures by using a load evaluation functions. Then, we determine parameters of the whole-body internal force for changing force distribution between arms and legs and whole-body joint torque ratio. We show a method to decrease search space for internal force parameters under symmetric posture assumptions. To evaluate developed methods, numerical experiments for least-loaded and most-loaded standing up from a chair motions and real-world experiments using a HRP-2 humanoid robot are presented.