Adaptive impedance control of a haptic teleoperation system for improved transparency

An adaptive impedance force control model of a haptic device for teleoperation is analyzed. A new force control model of the haptic device is constructed to investigate the dynamic effects of the user hand. Movements of the user hand may work as a force disturbance to the haptic force control system so that it is difficult to realize a good transparency. A model reference adaptive control (MRAC) is proposed to improve the transparency of the haptic device. A third order reference model with relative degree one is selected to satisfy requirements of rise time, settling time and overshoots. Experiments show that the force tracking performances are improved while force disturbances from the user hand are well compensated.