Robust integral sliding mode control of tower cranes

Abstract

In this study, integral sliding mode control is proposed for tower cranes to ensure precise tracking of the desired position while reducing the oscillations of the payload. The nonlinear robust controller is designed based on high fidelity nonlinear dynamical model, unlike the decoupled or linearized models used in the literature. The advantage of this approach is reducing the model uncertainties resulting in a lower control effort demand that would be required by the sliding mode controller. Moreover, the stability of the under-actuated tower crane system is analyzed using Lyapunov theory to guarantee the practical stability of error dynamics. Experimental results of the proposed control approach are compared with conventional sliding mode control to show its effectiveness and robustness against real system uncertainties.