Bilateral matched impedance teleoperation with application to excavator control

A bilateral teleoperation controller is presented in the article. The master and slave manipulators are controlled in impedance mode, with their target impedances adjusted in a dual manner to match high or low impedance environments. The adjustment rules presented use the relative sizes of forces and velocities to simply interpolate between low and high impedance controllers. The method was justified by the success of dual-hybrid teleoperation and is demonstrated to work using a simulator driven by a maglev force-feedback joystick. Experimental results using the same maglev force-feedback joystick to control an excavator are also presented, demonstrating through a typical leveling task that this method can work well in practice. The ratio of forces to velocities for deciding the master and slave impedances seems to be an effective method for dealing with extreme environment conditions, namely, free motion or hard constraint.