Sensor location effect on flexible robot control

Abstract

The effect of sensors collocated and noncollocated with robot actuators is simulated using a control strategy for a flexible robot. A 12.6 m /spl times/ 12.6 m square trajectory is tracked with a Jacobian transpose control law. Results are initially obtained for nonadaptive control then for fuzzy logic system (FLS) adaptive control. Sensors collocated with joint actuators do not capture flexure and nonminimum phase response while a noncollocated sensor captures inherent nonminimum phase response causing control action delays. Time delay in the feedback loop simulates nonminimum phase response and time delay in the feed forward control loop provides correction. Results demonstrate minimal correction of nonminimum phase response for nonadaptive control but significantly improved results with FLS adaptive control for collocated and noncollocated sensors.