A simple redesign of model reference adaptive control with actuator failures

A simple design method of model reference adaptive control for processes with unknown actuator failures of the freezing or lock-in-place type, is developed in the present manuscript. It is shown that the proposed design procedure can be applied to high relative degree cases without complicated control structures, and that global boundedness of the systems is assured for arbitrary failure patterns. The output errors converge to residual regions whose magnitudes can be made arbitrarily small by choosing design parameters in the high-gain observers.