Adaptive Pulse Output Feedback Controller Based on Second-Order Sliding Mode: Methodology and Application

This brief proposes an adaptive version of a second-order sliding mode (SOSM) controller with a gain for which switching variations are forced under some adequate conditions. The sampled controller requires no time derivative of the sliding variable but only the sign of the sliding variable. A practical SOSM is ensured in spite of bounded perturbations and uncertainties with unknown bounds. The gain adaptation law ensures obtaining a sufficient gain required for the convergence of the system. The methodological and experimental results are presented in this brief, the experimental part concerning the application of the proposed adaptive controller to the position control of an electropneumatic actuator.