A study on a class of MRAC algorithms

A class of model reference adaptive control (MRAC) algorithms is investigated which has the special property that the Lyapunov function (and its associated time derivative) describing convergence are quadratic functions of both the position tracking error and the parameter estimation error. A nonlinear equation describing the class of algorithms that provide this type of adaptation is derived. One possible solution to this nonlinear equation is proposed which is stable and produces consistent parameter estimates.