Output feedback stabilization of nonlinear feedforward systems using arbitrarily bounded control

In this paper, we consider the output feedback stabilization problem of a class of nonlinear feedforward (upper triangular) systems, of which the stabilization using an arbitrarily bounded controller has not been addressed previously. This stabilization is accomplished here via nested saturation linear control and dynamic compensator. The novelty in such an approach is that the maximum controller value can be set prior to designing the control, whereas in similar design schemes the maximum controller level is required to be sufficiently small.