A MODEL-BASED SLIDING MODE CONTROLLER FOR ROBOT MANIPULATORS

摘要

A generalized model-based sliding mode controller for robot trajectory tracking is proposed, which incorporates the full-order, nonlinear, uncertain actuator dynamics in control law design. The problem of chattering is alleviated by replacing the discontinuous sliding mode control in the vicinity of the sliding mode by a high-gain, continuous controller, resulting in dual mode control. Independent joint control, offline feedforward control, and online feedforward control laws are derived. Simulation results are presented for the first three links of the PUMA 560 arm to illustrate their effectiveness. The proposed nonadaptive control technique exhibits robustness to parametric uncertainties and payload variations and provides a trade-off between simplicity of implementation and precision of tracking.