Tracking approach of double pendulum cranes with variable rope lengths using sliding mode technique

Cranes are widely employed for transportation in many industrial fields. However, strong couplings and high nonlinearities increase difficulty of designing effective control methods for crane systems. Additionally, complex environments may bring uncertainties and unfavorable factors for the control problem. In this paper, we design an effective tracking approach for double pendulum cranes considering variable rope lengths problem by using sliding mode technique, to further improve the robustness and achieve the control objectives of accurate tracking, while effective suppression for double pendulum swing is also ensured. We design a proper sliding mode surface containing all state variables, which effectively suppresses swing angles of the payload and the hook. Then, the time delay estimator technique is used to estimate parameter uncertainty-related terms and the estimation errors are effectively tackled by using sliding mode technique. The effectiveness is rigorously proved by Lyapunov stability theory. At last, comprehensive simulations are implemented to show the proper performance.& COPY; 2022 ISA. Published by Elsevier Ltd. All rights reserved.

Automated summary

In this paper, an effective tracking approach for double pendulum cranes is designed using sliding mode technique to improve robustness and achieve accurate tracking objectives while suppressing double pendulum swing. The approach includes a proper sliding mode surface to suppress swing angles, as well as a time delay estimator technique to handle parameter uncertainty-related terms. The effectiveness of the approach is rigorously proved by Lyapunov stability theory, and comprehensive simulations are implemented to demonstrate its performance.