LPV-MRAC Method for Aircraft with Structural Damage

Abrupt structural damage poses significant challenges to the flight safety and flight quality of aircraft. In this paper, a direct model reference adaptive control (MRAC) method based on a linear parameter-varying (LPV) model is proposed to recover the control performance and flight quality of damaged aircraft. The design of the controller is based on a polytopic LPV model and the higher order singular value decomposition (HOSVD) model reduction method to reduce the computational cost of identifying the damaged aircraft model. The proposed controller also extends a previous MRAC method which assumes the input matrix is unchanged for different damage cases by identifying an uncertain input parameter online. The developed LPV-MRAC method is validated by simulation on NASA's generic transport model (GTM) with left wing tip loss damage and shown to be capable of compensating the damage effects and restoring the aircraft's control performance shortly after the damage. The flight quality of the closed-loop damaged aircraft is also evaluated by the C-star criterion and shown to be within Class I under the proposed controller.