Impedance control for biped modular reconfigurable robot with gait coordination under complex environmental contact

In this paper, an impedance control algorithm for biped modular reconfigurable robot (MRR) is proposed for steady walking. Base on Newton-Euler iterative method, the dynamic models of legs and hips are established respectively. Considering the contact state between environment and foot, a contact model is established. The desired trajectory is generated based on zero moment point method (ZMP). In the process of biped MRR movement, aiming at the problem of gait coordination in the single support phase (SSP) and the double support phase (DSP), the impedance coordination control algorithm is introduced, and the impedance controller for both legs is designed. The leg track the desired trajectory and achieve the purpose of stable walking. The stability of the impedance controller is proved by Lyapunov theory. Finally, the simulation results demonstrate the effectiveness of the proposed control method.