Motion control of a quadruped robot in unknown rough terrains using 3D spring damper leg model

This paper presents a simple method to control the motion of a quadruped robot in unknown rough terrains using a full dynamic model. First, using typical stiffness control method, the four legs´ behavior is approximated to 3D spring damper systems. By this way, we can easily derive the dynamic equations of motion in Cartesian space. Based on these equations, a control strategy is proposed to obtain the asymptotical stability of the system. In addition, a reflex signal is also introduced to control the rotational disturbance of the robot body. Finally, dynamic simulation of a quadruped walking robot is performed on several unknown rough terrains to verify the proposed method.