Bilateral Impedance Control For Telemanipulators

Abstract

The research investigates a new method of control for telemanipulators called bilateral impedance control. This new method differs from previous ap"roaches in that interaction forces are used as the communication signals betWeen the master and slave rooots. The main advantage of bilateral impedance control is that it permits the arbitrary specification of desired system performance characteristics. Performance c!'n be described by a set of three independent parameters that relate the robot forces and positions. nis set of parameters may includ.: the force ratio, the position ratio,.lid the robot impedances. The s)stem stability is analyzed with the Nyquist Criterion to obtain two conditions that are sufficient to guarantee closed-loop stabilit)'. This control architecture is implemented on a telemanipulator having seven degrees of freedom. The theoretical predictions for performance and stability are experimentally verified.