Safe tracking control of Euler-Lagrangian systems based on a novel adaptive super-twisting algorithm

In this paper, a novel adaptive second-order sliding mode controller is designed for Euler-Lagrangian systems with hard safety constraints. Different from the conventional sliding mode controllers, the proposed method provides adaptive controller parameters, such that the robustness of the controller is ensured without bringing up chattering. The controller also guarantees strict compliance to hard state-dependent inequality constraints. The asymptotic convergence of the tracking errors of the proposed controller is proven by a direct Lyapunov method. Finally, the proposed controller is validated by numerical simulation on a three-degreeof- freedom robot platform. The results confirm that the controller ensures strict constraint compliance and precise trajectory tracking, which reveals its potential applicability to the safe control of mechatronic systems.