A friction compensation in twin drive system

A method of friction compensation based on a twin drive system is discussed in the paper. The twin drive system in composed of two motors connected by a differential mechanism. Then the generated torque of the system is the torque difference between two motors. Also these motors are continuously driven to reduce the influence of static friction in each motor even if the system has a stationary motion. This is one of the remarkable points in the proposed approach of twin drive system. Furthermore the paper introduces virtual coordinates to construct the controller. The validity of the proposed system is confirmed by several experimental results.