Force Tracking Impedance Control of Robot-Tissue Interaction With a Hunt-Crosseley Model

Control of soft tissues and robot interaction force has a lot of application in rehabilitation, robotic surgery and so on. The objective of this paper is to regulate interaction force between robot and soft tissue by using impedance control. A Hunt-Crossley nonlinear model is used as a soft tissue model. So as to obtain an accurate force tracking by impedance control, a virtual reference trajectory is generated by means of online estimation of tissue parameters using smooth projection. The stability of overall closed-loop system is investigated via Lyapunov’s direct method. Because of using impedance control, the proposed control methodology can be used for both noncontact and contact phase of robot and tissue interaction. Finally, simulation results performed on a two-link rotary robot