Comparison of nonlinear control design techniques on a model of the Caltech ducted fan

In this paper we compare different nonlinear control design methods by appl ying them to the planar model of a ducted fan engine. The methods used rang e from Jacobian linearization of the nonlinear plant and designing an LQR c ontroller, to using model predictive control and linear parameter varying m ethods. The controller design can be divided into two steps. The first step requires the derivation of a control Lyapunov function (CLF), while the se cond involves using an existing CLF to generate a controller. The main prem ise of this paper is that by combining the best of these two phases, it is possible to find controllers that achieve superior performance when compare d to those that apply each phase independently. All of the results are comp ared to the optimal solution which is approximated by solving a trajectory optimization problem with a sufficiently large time horizon. (C) 2001 Publi shed by Elsevier Science Ltd.