Nonlinear minimum-time control with pre- and post-actuation

This article studies the time-optimal output transition problem to change the system output, from an initial value y(t) = y (for all time t ≤ 0) to a final value y(t) = y (for all time t ≥ T ), for invertible nonlinear systems. The main contribution of the article is to show that the use of preand post-actuation input outside the transition interval IT = [0, T ] can reduce the transition time T beyond the standard bang–bang-type inputs for optimal state transition. The advantage of using preand post-actuation is demonstrated with an illustrative nonlinear example. © 2011 Elsevier Ltd. All rights reserved.