Stable Linear Bilateral Teleoperation System Employing an Impedance Control Via Estimated External Forces

We propose a new impedance control algorithm for delayed linear bilateral teleoperation systems. In the presented control strategy, with regard to a preferred impedance model for the master and slave robots, a special dynamic feature at the human and the master robot along with the slave robot and environment interface is proposed. In addition, external forces signals including operator and remote environmental forces are used in the controller to attain desired impedance model. A force estimation scheme is presented to remove measurement of external forces. Then, the desired impedance model is located into an appropriate sliding-mode control scheme to compensate the parameters uncertainties emerged by external force estimation errors. Then, the absolute stability criterion is used to investigate the stability of the closed-loop teleoperation system along with transparency. Consequently, the control strategy is implemented on ۱-DOF robotic system as the master and slave robots. Simulation results verify the effectiveness of the presented impedance controller by using estimated external forces.