LAUSR

Dutch roll motion is a type of aircraft lateral/directional oscillation, and its control problem has two main challenges. First, a multiple-input–multiple-output (MIMO) non-affine Dutch roll dynamics may result in nonzero equilibriums and unstable oscillations due to complex nonlinearities and disturbances. Second, the Dutch roll dynamical model is non-affine nonlinear, because it has nonlinear relationships not only with the state variables but also with the control inputs, which brings more difficulties to control it. Therefore, according to the analysis results of Dutch roll dynamics, a robust adaptive non-affine controller is designed to suppress the unstable oscillations with disturbances. Sliding mode method, fuzzy logic systems, and adaptive techniques are combined to construct the non-affine controller, without the need for the exact bound values of disturbances except for the theoretic proof. The simulation results show that the oscillations can be effectively suppressed using the proposed controller.