Selection of network parameters in wireless control of bilateral teleoperated manipulators

This paper describes how to establish performance charts for selection of network parameters for effective utilization of a bilateral teleoperated manipulator working under a wireless communication channel. The goal is to construct a set of charts that help researchers and engineers to select appropriate parameters of wireless network setup for a known configuration of environment obstruction. To achieve this goal, a teleoperated setup comprising a master haptic device, a slave manipulator dynamic simulator, and a communication channel emulated using the network simulator version 2 (NS2) simulator is first developed. Next, performance indices are defined to evaluate the quality of position tracking of the slave manipulator end-effector and force tracking of the master haptic. Three indices chosen in this paper are the integral of squared position and force errors, the integral of absolute position and force error, and the amplitude of position and force overshoot. Extensive experiments on the developed setup are then conducted to study effects of time-varying packet loss on the performance of the teleoperated system. The largest mean packet loss, at which the system exhibits satisfactory tracking, is then quantified. This packet loss is used as an indicator to define regions representing the quality of tracking. The effectiveness of the proposed technique is validated by testing a fully instrumented hydraulically actuated system under various real wireless channel scenarios.