An adaptive nonlinear output feedback controller using dynamic bounding with an aircraft control application

Abstract

An adaptive output feedback control scheme is developed for a class of nonlinear systems with uncertain nonlinearities, which are bounded by both static and dynamic functions of the system output, and with actuator failures whose failure time instants, patterns and values are unknown, as motivated from an aircraft flight control application. An adaptive backstepping control law using dynamic bounding is constructed to deal with unknown actuator failures as well as system parameter and dynamics uncertainties to guarantee desired system performance. Complete stability and performance analysis and illustrative simulation results of an application to aircraft flight control are presented.

Adaptive Output Tracking Control for Nonlinear Systems with Failed Actuators and Aircraft Flight System Applications

“…Example 1. The nonlinear longitudinal dynamics of the twin otter aircraft [1,7,27] is used for our actuator failure compensation study. Choosing the velocity, angle of attack, pitch angle, and pitch rate as the states 1 , 2 , 3 , and 4 and the elevator angles of an augmented two-piece elevator as the inputs 1 , 2 , the system can be modeled aṡ…”

“…Due to the unknown failure patterns, times, and values, it has been an important and challenging research problem. Remarkable progress has been made in the area, such as adaptive control [1][2][3][4][5][6][7][8][9][10], sliding-mode based designs [11][12][13][14], switching based designs [15][16][17], fault-detection diagnosis based designs, fuzzy systems based designs, and neuralnetwork based designs. Since adaptive designs use an adaptive controller to accommodate the uncertainties, it has been extensively employed.…”

“…(1) We relax the condition imposed by Tang et al in [5][6][7]. (2) An adaptive output feedback controller is developed with switching laws [15,16].…”

Modular‐based adaptive control of uncertain nonlinear time‐varying systems with piecewise jumping parameters

“…Although these existing results achieve stability and improve performance, they are mainly dependent upon integrator backstepping method with tuning function and Kreisselmeier/Marino&Tomei (K/MT) filters; on the other hand, they also require the time variations of the parameters to be either sufficiently slow or infrequent jumps. Namely, the rate of parameter variations is constrained by a sufficiently small upper bound.In this paper, on the basis of our recent preliminary work in [14], we further address the issue of controlling uncertain nonlinear time-varying systems by utilizing the modular-based adaptive control scheme in which the controller module and the parameter identifier module are designed separately, which is different from the tuning function approach adopted in [9], [15], [16,17], and [18] and the output feedback approach in [19] and [20]. More importantly, the usual restrictive parameter assumption of sufficiently slow time variations and infrequent jumps is removed.…”

“…In this paper, on the basis of our recent preliminary work in [14], we further address the issue of controlling uncertain nonlinear time-varying systems by utilizing the modular-based adaptive control scheme in which the controller module and the parameter identifier module are designed separately, which is different from the tuning function approach adopted in [9], [15], [16,17], and [18] and the output feedback approach in [19] and [20]. More importantly, the usual restrictive parameter assumption of sufficiently slow time variations and infrequent jumps is removed.…”