Robust adaptive control of a slewing active structure

In this paper ne present a hybrid adaptive control for rigid body slewing and constant amplitude feedback control for residual vibration suppression for a slewing active structure. This system consists of 1) a single-axis servo DC motor and encoder for rigid motion, slewing and 2) a graphite/epoxy composite smart link with embedded strain sensors/actuators for active vibration suppression. The results of this study include the theoretical development and preliminary experimental results. The hybrid control algorithm uses; the output sensor data from the encoder and strain sensor along with filters to derive velocity information to compute the control for the motor and strain actuators. Near-minimum time maneuvers based on an equivalent rigid structure are used to slew the flexible active structure. The tip mass was varied so that the robustness of the control system could be evaluated. Experimental slewing studies were performed to compare the benefits of using active rather than passive structures. The experimental results show a reduction in residual vibration and settling time for the active structure case.