Dynamics and control of flexible manipulators using variable-speed control moment gyros

In this paper, the variable-speed control moment gyros (VS-CMGs) are adopted as actuators for vibration suppression of space flexible manipulators. They are directly mounted on the flexible links of the manipulator. Such system can be viewed as a flexible multibody system in chain topology actuated by both joint motors and VS-CMGs. We first develop a general approach for establishing the system equations of motion through Kane’s method. Then, two controllers are designed for trajectory tracking and vibration suppression of the flexible manipulator: one is an inverse dynamics control, whereas the other is based on the singular perturbation method. The proposed two control strategies are applied to a free-flying platform with a flexible manipulator. Numerical results show that the VS-CMGs can significantly suppress the induced vibration of the flexible links during the large angle maneuver.