Finite-Time Trajectory Tracking Control for Overhead Crane Systems Subject to Unknown Disturbances

In this paper, a finite-time trajectory tracking control method for overhead crane systems with unknown disturbances is proposed. The controller is designed in the framework of observer-based control design, therefore, it works well even in the presence of internal and external disturbances. Prior knowledge of the system parameters, including the payload mass, the trolley mass, the cable length, and the friction-related coefficients, is not required for the designed controller. Moreover, the proposed controller can prove the state convergence on the sliding surface without any approximations to the original dynamic equations. More precisely, to estimate unknown disturbances, a terminal sliding mode observer is designed. And then, a finite-time trajectory tracking controller is synthesized by using the estimated information. As shown by Lyapunov techniques, the designed controller guarantees the finite-time tracking result. The simulation results are provided to illustrate the superior control performance and strong robustness of the proposed finite-time trajectory tracking control method.