Enhancing prescribed performance of tracking control using monotone tube boundaries

In this paper, we study the performance enhancement of tracking control for a class of nonlinear systems with prescribed performance, by employing a novel pair of prescribed monotone tube boundary functions. Compared to the standard prescribed performance approach, the key merit relies on the capability to assign some quantitative indices (e.g., overshoot, accuracy and convergence time) – which are widely required in industry – in terms of the novel links between these indices and the proposed boundary functions. We provide a constructive solution to achieve the pre-assigned performance, which is characterized by forward invariance and boundedness of the closed loop.