Computations and time-optimal controls

A new control method, the switching time computation (STC) method (Kaya, C. Y. and J. L. Noakes, Proc. 33rd IEEE Conf. on Decision and Control, Orlando, FL, 1994, pp. 3823-3824), is described in detail for single-input non-linear systems, and the mathematical reasoning behind it is explained. A concatenation of constant-input arcs is used to get from an initial point to the target, and an optimization procedure is employed to find the necessary time lengths of the arcs. General difficulties of the STC method in finding the necessary arc time lengths are emphasized and exemplified. The STC method is incorporated in a time-optimal bang-bang control (TOBC) algorithm. The results of the application of the TOBC algorithm to the van der Pol equation, a third-order non-linear system and a non-linear dynamical model of the F-8 aircraft are presented. The STC method is shown to be fast by making comparisons with a general optimal control software package.