Fuzzy Adaptive Output Feedback Tracking Control of VTOL Aircraft With Uncertain Input Coupling and Input-Dependent Disturbances

Abstract

This paper proposes fuzzy adaptive output feedback tracking control method for VTOL (vertical takeoff and landing) aircraft. Since uncertainties exist in the input coupling parameter due to its dependence on the physical parameters and also unknown disturbances can occur in the form of input-dependent accelerations in dynamics, these should be compensated at the same time. To this end, the dynamics with input-dependent disturbances are first rigorously derived based on the general form of acceleration disturbance vector in VTOL system. Second, the nonlinear velocity observer is designed to estimate the velocity information not available in the actual situation such that the output feedback tracking control can be achieved even in the presence of uncertain input coupling and disturbances, which is not possible in the case of previous works. Third, fuzzy adaptive observer is designed to estimate both unknown input coupling coefficient and input-dependent disturbances. Finally, the fuzzy adaptive output tracking controller is designed based on the nonlinear velocity observer and the fuzzy adaptive observer. The trajectory tracking errors can be guaranteed to be globally ultimately bounded and their ultimate bounds can be adjusted appropriately. Both stability analysis and simulation results demonstrate the effectiveness of the proposed method against uncertainties and disturbances in VTOL system. Index Terms-Fuzzy adaptive output feedback tracking control, VTOL aircraft, unknown coupling coefficient, acceleration disturbance, fuzzy adaptive observer.

Co-design of output feedback laws and event-triggering conditions for theL2-stabilization of linear systems

“…where x c ∈ R nc is the controller state,ŷ ∈ R ny is the most recently transmitted value of the output measurement y to the controller, and d u ∈ R nu is a vector of noises affecting the control input, e.g., additive torque disturbance in robotic systems [7] or acceleration disturbances on the control input in the vertical takeoff and landing (VTOL) aircraft [5]. We assume that the signal d u is absolutely continuous and its time-derivative exists for almost all the time and is in L 2 .…”

Neuroadaptive Dynamic Surface Asymptotic Tracking Control of a VTOL Aircraft with Unknown Dynamics and External Disturbances

“…In [4], the asymptotic trajectory tracking control problem of a VTOL aircraft with restricted inputs was achieved by utilizing the designed smooth bounded controller. In the work of [5], the authors applied the fuzzy adaptive output feedback tracking control method to solve the tracking problem of a VTOL aircraft with uncertain input coupling and input-dependent disturbances. For the planar VTOL aircraft system, a number of effective control methods have been proposed to solve the tracking control and stability problems such as the backstepping control method [6,7], the alternative nonlinear control strategy [8] and the gain-scheduled control method [9].…”

Observer-Based Fault Tolerant Control for a Class of Nonlinear Systems via Filter and Neural Network

“…In [6], a disturbance rejection tracking control scheme was proposed for an airplane in the presence of external time-dependent disturbances and internal uncertainties by utilizing a robust feedback control policy such that the controlled system is robust to the disturbances and uncertainties. In [7], the tracking control problem for vertical takeoff and landing aircraft with unknown disturbances was dealt with by designing a control method combined nonlinear velocity observer with fuzzy adaptive observer. The effectiveness of such method was verified via stability analysis and simulation results.…”