Multivariable MRAC for aircraft with abrupt damages

This paper addresses the compensation of aircraft damages using the direct adaptive control approach. The dynamical modeling of aircraft with damages is first introduced, which demonstrates the complex dynamics when asymmetric mass distribution occurs as the result of damages. An approximate model is proposed under certain flight conditions, and its linearization is performed, which captures the key dynamic features of the aircraft under asymmetric damages. Multivariable model reference adaptive control (MRAC) scheme is demonstrated for control of aircraft in both healthy and post-damage situations, by adapting controller parameters autonomously after the damages occur, without the knowledge of the damage time instants, nor the damage structure and values. Relaxation of design conditions is illustrated by expanding the controller structure and re-designing the adaptive law, to further reduce the need of the post-damage system knowledge.