Robust Interference Suppression and Tracking Control of Underactuated Systems Based on Equivalent Input Disturbance

Aiming at the anti-sway control of underactuation System, a new control technique is proposed in this paper to achieve the high precision trajectory tracking and good robust disturbance rejection of an underactuated system. Using homeomorphic coordinate transformation to transform the original system into a newer system with simpler structure. Then, the linear and nonlinear parts of the new system are separated, and the non-linear part is regarded as the virtual disturbance of the linear part. By constructing the no-error internal model disturbance compensator, the optimal non-static disturbance rejection problem with persistent disturbance is transformed into the optimal control problem of the perturbed augmented system makes the closed-loop system obtain good tracking characteristics and interference suppression characteristics. Finally, through the homomorphism of coordinate transformation, the original underactuation System is controlled. By applying it to a two degree of freedom underactuated crane, the numerical simulation results show that the improved equivalent input disturbance control strategy can achieve high precision tracking location and robust disturbance rejection of crane, and it can effectively improve the efficiency of crane.