Transparency improvement in a bilateral motion-scaling control using Kalman-filter-based disturbance observer

Abstract

This paper proposes a new wideband bilateral motion-scaling control to apply in the small size robot system. The scaling Hadamard matrix is applied to reduce or magnify the force and position response of bilateral motion-scaling control. The technique to estimate the action/reaction forces of master-slave robot is designed using Kalman-filter based disturbance observer (KFDOB). Optical encoder and acceleration signals were fused to estimate contact forces occurring during an experiment. With the bilateral motion-scaling control and KFDOB, we can control the small scale master-slave robot with high precision. Comparative experiments show the KFDOB and its multi-sensor fusion to provide performance superior to that of previously disturbance observer. As seen in the experimental results, it is clear that high transparency and good perception of the environmental stiffness with the response of the master-slave robot can be achieve successfully. An additional result of FFT analysis which guarantees noise compensation is also presented.