A Robust Adaptive Nonlinear Control Design

An adaptive control design procedure for a class of nonlinear systems with both parametric uncertainty and unknown nonlinearities is presented. The unknown nonlinearities lie within some "bounding functions" which are assumed to be partially known. The key assumption is that the uncertain terms satisfy a "triangularity condition." As illustrated by examples, the proposed design procedure expands the class of nonlinear systems for which global adaptive stabilization methods can be applied. The overall adaptive scheme is shown to guarantee global uniform ultimate boundedness.