Modular backstepping design of an estimation-based sliding mode controller for uncertain nonlinear plants

A partially recursive backstepping-like procedure to design estimation-based controllers for uncertain nonlinear systems is presented. Its motivation relies on the intent of reducing the computational load of the n-steps backstepping design by exploiting the promising features of second order sliding mode control. The proposed approach exhibits modularity, in the sense that the controller is proved to guarantee input-to-state stability regardless of the choice of the parameter estimation mechanism