Robust Stabilization Technique for the Leader Steering Slung-Load System/Using Sliding Mode Control

A multi-lift transportation system, the leader steering slung-load system, is proposed as an alternative to increase the payload of small vehicles. This paper describes a robust stabilization technique for the system using sliding mode control (SMC). SMC is known as a straight-forward design method for the control of nonlinear systems with multi-inputs and multi-outputs (MIMO). The sliding surfaces based on measurable outputs are identified. The control inputs (the acceleration command for each vehicle) are designed. To tune the sliding mode control gains to match the outputs in a one-by-one manner, the control inputs are decomposed. Estimators of the nonmeasurable states are developed. Sliding mode control laws proven under the Lyapunov stability are designed. Finally, simulation results show that stable slung-load transportation can be accomplished using the method suggested.