High-Order Fully Actuated Control Approaches of Flexible Servo Systems Based on Singular Perturbation Theory

This work presents a high-order fully actuated (HOFA) control approach for flexible servo (FS) systems via singular perturbation (SP) method. The HOFA approach has the advantages of simplicity and intuition on the control design of FS systems due to its full-actuation feature, but suffers the high-order derivative problem of signals. To overcome this difficulty, this article separates the original system via the SP approach with two time-scale properties. By using the slow model, the state feedback control with dynamical compensator is designed via HOFA approach to obtain the desired tracking error dynamics. It not only avoids the high-order derivatives of signals but also improves the disturbance rejection. Based on the fast model, a simple active damping control is applied for the resonance suppression, aiming at obtaining larger control gains to further increase the control accuracy. SP theory is employed for stability analysis of the full system in the presence of uncertainties. Simulations and experiments are carried out to verify the effectiveness of the proposed approach.