Output-Based Model Reference Adaptive Control of Satellite Manipulator

Abstract

The limited availability of energy resources in space implementations requires the use of low-power and low-capacity actuators in satellite manipulators. This constraint makes it necessary to employ the manipulator structure to be lightweight in order to maintain task performance; however, the resulting increase in structural flexibility makes position control and vibration suppression problems more challenging. This study aims to enhance system performance in the position control problem of a flexible-link satellite manipulator and evaluate control performance under the influence of flexible dynamics while suppressing vibrations indirectly. In this context, Cascade PID control and Model Reference Adaptive Control (MRAC) structures are comparatively investigated, and their performances are analyzed in a simulation environment. The results show that MRAC-based control structure achieves higher tracking accuracy and more effective vibration suppression under the presence of system uncertainties and flexible dynamics, while both control methods provide stable tracking performance. This study represents a comparative evaluation of MRAC-based and Cascade PID control methods for lightweight and flexible manipulator systems used in energy-constrained space missions, and it reveals that MRAC-based control strategies offer a robust and practical solution for such systems.