Locomotion control of a biped robot through a feedback CPG network

Abstract

This paper proposes a locomotion control system for biped robots by using a network of Central Pattern Generators (CPGs) implemented with Matsuoka’s oscillators. The proposed control system is able to control the system behaviour with a few parameters by using simple rhythmical signals. A network topology is proposed in order to control the generation of trajectories for a biped robot in the joint-space both in the sagittal and coronal planes. The feedback signals are directly fed into the network for controlling the robot’s posture and resetting the phase of the locomotion pattern in order to prevent the robot from falling down whenever a risk situation arises. A Genetic Algorithm is used to find optimal parameters for the system in open-loop. The system behaviour in closed-loop has been studied and analysed through extensive simulations. Finally, a real NAO humanoid robot has been used in order to validate the proposed control scheme.