Stability and transparency of adaptive controller based four-channel bilateral control system with communication delay

Bilateral teleoperation has a wide range of application such as deep-sea operation, space mission, etc. However, the presence of communication delay between master robot and slave robot significantly degrades transparency and stability. Although adaptive controller based four-channel bilateral control is one of the approach to achieve high transparency against communication delay, stability of the adaptive controller based system has not been analyzed yet. The adaptive controller changes the controller gain depending on the stiffness of contact objects. Therefore, this paper analyzes stability and transparency of adaptive controller based four-channel bilateral control system with communication delay. The validity of analysis is confirmed by experiments.