Variable Structure Adaptive Control of Wing-Rock Motion of Slender Delta Wings

Based on the variable structure model reference adaptive control theory, a new control system for the control of wing-rock motion of slender delta wings, using only roll angle measurement, is designed. For the derivation of the control law, it is assumed that the aerodynamic parameters and the structure of the aerodynamic nonlinear functions in the model are unknown. Moreover, it is assumed that disturbance input due to wind gust is present in the system. It is shown that, in the closed-loop system designed using bounds on uncertain functions, the roll angle tracks given reference trajectory, and the wing-rock motion is suppressed. Digital simulation results show that the closed-loop system has good transient behavior and robustness to the uncertainties and disturbance input