Design of adaptive sliding mode controllers for perturbed nonlinear systems with partial unmeasurable states and state constraints

A sliding mode control (SMC) strategy is proposed in this paper for a class of perturbed nonlinear systems with unmeasurable states and state constraints to deal the tracking problems. First all, partial observer designed solving problems due states. The estimation errors will approach zero finite time. Secondly, based on barrier Lyapunov function, one designs surface function an adaptive controller ensure that have ability track desired signals. Moreover, error capable converging time without violating given state’s constraints. Perturbation estimator mechanisms are also utilized so there no need know upper bounds perturbations perturbation advance. Finally, numerical example practical application provided demonstrate effectiveness applicability strategy.