Design Optimization of Musculoskeletal Humanoids Maximizing the Redundancy to Compensate for Muscle Rupture

Abstract

The redundant muscle arrangement allowing for variable stiffness control is one of the most important advantages of musculoskeletal humanoids. In this study, we focus on one feature of the redundancy, which enables the humanoid to keep moving even if one of its muscles breaks, an advantage that has not been dealt with in many studies. In order to make the most of this advantage, the design of muscle arrangement is optimized by considering the maximization of minimum available torque that can be exerted when one muscle breaks. This method is applied to the elbow of a musculoskeletal humanoid Musashi with simulations, the design policy is extracted from the optimization results, and its effectiveness is confirmed with the actual robot.