inear Adaptive Inverse Control

An unknown linear plant will track an input command signal if the plant is driven by a controller whose transfer function approximates the inverse of the plant transfer function. An adaptive inverse identification process can be used to obtain a stable controller, even if the plant is nonminimum phase. A model-reference version of this idea allows system dynamics to closely approximate desired reference-model dynamics. No direct feedback is used, except that the plant output is monitored and utilized by an adaptive algorithm to adjust the parameters of the controller. Although nonlinear plants do not have transfer functions, the same idea works well for nonlinear plants.