Robust Control of Free-floating Space Flexible Manipulator in Joint Space

The robust control and active vibration control for free-floating space flexible manipulator with parameter uncertainties are studied. The dynamic equations of the system are developed by using the Lagrangian assumed modes methods, it is verified that the dynamic equation can be linearly dependent on a group of inertial parameters. Based on the results and under the assumption of two-time scale, singular perturbation model of the space flexible manipulator system is obtained. The fast subsystem controller will damp out the vibration of the flexible link using optimal Linear Quadratic Regulator (LQR) method. The slow subsystem robust controller dominates the trajectory tracking in joint space. In particular, the control scheme doesn’t require measuring the position, velocity nor acceleration of the base. The numerical simulation is carried out, which confirms the controller proposed is feasible and effective. Keywords—space flexible manipulator, robust control, active vibration control, singular perturbation approach, joint space