|LPV Modeling and Tracking Control of Dissimilar Redundant Actuation System for Civil Aircraft
Salman Ijaz*, Mirza Tariq Hamayun, Haris Anwar, Lin Yan, and Mingkuo Li
International Journal of Control, Automation, and Systems, vol. 17, no. 3, pp.705-715, 2019
Abstract : "Dissimilar redundant actuation systems (DRAS) are in practice in advanced aircraft in order to increase
reliability and to resolve the actuator failure issue due to common cause. This paper addresses the problem of
force fighting that occurs due to dynamics mismatch of two dissimilar actuators in DRAS and provides a method to
achieve precise tracking of aircraft control surface. The nonlinear system dynamics are first transformed into linear
parameter varying (LPV) form using recursive least square (RLS) method. The LPV observer based controller is
then designed to synchronize the positions of dissimilar actuators in DRAS and to drive the control surface smoothly.
By applying linear matrix inequalities (LMIs), parameter dependent Lyapunov function (PDLF) is obtained to
achieve global stability and to compute the controller and observer gains. To test controller according to real
flight condition, an external disturbance signal that acts as air load is applied at the control surface input. Several
simulations on the nonlinear system validate the dominant performance of proposed controller as compared to the
existing methods in literature."
"Dissimilar redundant actuation system, force fighting, linear matrix inequality, linear parameter varying, optimization."