Robust Prescribed Performance Control under Given Constraints for Systems with Relative Degree One

The problem of prescribed performance control under given constraints on the amplitude and rate of control signal is considered for dynamic systems with relative degree one in the presence of parametric uncertainty and external disturbances. Using the ideas of feedback design based on sat-function differentiable approximation and augmented perturbation estimation, a novel nonlinear robust control law is proposed, which, if the parameters are suitably chosen, provides a solution to the problem under consideration. The parameter calculation procedure is reduced to solving linear inequalities, which feasibility is proved analytically. Illustrative example corroborates theoretical results.