Analysis of a type of model reference-adaptive control system

A model reference-adaptive control system, in which the parameter-adjusting signals are derived from estimates of the partial derivatives of error with respect to those parameters, is analysed. Stability of both single- and multiparameter systems is investigated using the second method of Lyapunov. Limitations on the speed of adaptation of both single- and multiparameter systems are derived. A four-parameter system suitable for the pitch control of an aeroplane is simulated on an analogue computer and the theoretical predictions are confirmed.