Study on Dynamics Identification of the Foot Viscoelasticity of a Humanoid Robot

This paper describes the dynamics identification of the foot viscoelasticity of humanoid robots. It is important to know correctly dynamics parameters of link and joint which constitute a robot for its simulation and model based control. When walking, humanoids receive impulsive force at each step. Some humanoids have shock absorber and rubber bush in their soles. In simulation, accuracy of inertial parameters and viscoelastic parameters that compose robot model is important to simulate their motion accurately. We identify the viscoelastic parameters of HRP2 using the base-link dynamics and viscoelastic joint dynamics. We modeled the humanoid robot HRP2 sole rubber bush with a simple structure and identify the viscoelastic parameters with parallel model that is composed of elasticity and viscosity and offset torque. We finally validate the identified parameters with some additional motions. 