Supervised switching control of a deployable manipulator system

This paper presents a supervisory system for controller switching as applied to ground-based and space-based deployable manipulator systems. First, a finite family of candidate controllers is established so that the manipulator system performs satisfactorily under the control of one of the controllers, in the possible presence of model uncertainties, unknown parameters, time variance, nonlinearities, and variable operating conditions. A supervisory unit in the system monitors the performance of the manipulator. Based on this, a decision-making logic unit selects an appropriate controller from the family, and activates it while deactivating the currently active controller, so as to ensure proper performance. Capabilities of instantaneous switching and gradual switching using a switching function and a switching compensator are incorporated into the system. The performance of the supervised switching control system is evaluated through computer simulation of an innovative manipulator system consisting of a combination of revolute and prismatic degrees of freedom and joint and link flexibilities.