A Hybrid ZMP-CPG Based Walk Engine for Biped Robots

Abstract

Developing an optimized omnidirectional walking for biped robots is a challenging task due to their complex dynamics and kinematics. This paper proposes a hierarchical walk engine structure to generate fast and stable walking. In particular, this structure provides a closed-loop CPG-based omnidirectional walking that takes into account two human-inspired push recovery strategies. In addition, this structure is fully parametric and allows using a policy search algorithm to find the optimum parameters for the walking. To show the performance of the proposed structure, a set of experiments on a simulated NAO robot has been carried out. Experimental results demonstrate that the proposed structure is able to generate fast and stable omnidirectional walking. The maximum speed of forward walking that we have achieved was 59 cm/s.