Adaptive regulation of high-order lower-triangular systems: an adding a power integrator technique

In this paper, a new adaptive control technique called adding a power integ rator is proposed, for a class of linearly parametrized high-order nonlinea r systems that are of a lower-triangular structure, but neither feedback li nearizable nor affine in the control input. Using the adaptive adding a pow er integrator technique as a basic design tool, we show how to explicitly c onstruct, in a recursive manner, a smooth adaptive controller that solves t he problem of adaptive regulation with global stability. The development of the adding a power integrator technique leads to a significant relaxation on the system nonlinearities such as feedback linearizability and affinenes s, which are known to be two standard hypotheses made in the existing nonli near adaptive control schemes. (C) 2000 Elsevier Science B.V. All rights re served.