Design of Adaptive SOSM Controller Subject to Disturbances With Unknown Magnitudes

The work is dedicated to handling the issue of a new adaptive second-order sliding mode (ASOSM) controller design for a class of nonlinear systems subject to disturbances and nonlinear control gains with unknown magnitudes. Significantly, the proposed controller involves two adaptive parameters, which are generated from a dual-layer adaptive mechanism. The mechanism directs at the reestablishment of the upper bounds of the unknown disturbances and the handling of the nonlinear control gains. Through a combination of the mechanism and the finely renovated adding a power integrator technique, a novel design procedure is introduced to skillfully design an ASOSM controller. A rigorous Lyapunov analysis is afforded to evince the finite-time stability of the whole system. Finally, two illustrative examples are given to exhibit the effectiveness of the developed approach.