Model-based vibration suppression control for an articulated robot

This paper deals with a control technique of eliminating the transient vibration with respect to a waist axis of an articulated robot. This control technique is based on a model-based control using a time-varying control model in order to establish the damping effect at the mechanical part. The control model is composed of reduced-order electrical and mechanical parts. Parameters of the control model are set to follow the change of the natural frequency of the robot arm. This model estimates a load speed converted to the motor shaft. The difference between the estimated load speed and the motor speed is calculated dynamically, and is added to the velocity command to suppress the transient vibration. Simulations and experiments show satisfactory control results to reduce the transient vibration at the end-effector.