Robust output feedback control of fixed-wing aircraft

Abstract

Purpose This paper aims to devise a robust controller for the non-linear aircraft model using output feedback control topology in the presence of uncertain aerodynamic parameters. Design/methodology/approach Feedback linearization-based state feedback (SFB) controller is considered along with a robust outer loop control which is designed using Lyapunov’s second method. A high-gain observer (HGO) in accordance with the separation principle is used to implement the output feedback (OFB) control scheme. The robustness of the controller and observer is assessed by introducing uncertain aerodynamics coefficients in the dynamic model. The proposed scheme is validated using MATLAB/SIMULINK. Findings The efficacy of the proposed scheme is authenticated with the simulation results which show that HGO-based OFB control achieves the SFB control performance for a small value of the high-gain parameter in the presence of uncertain aerodynamic parameters. Originality/value A HGO for the non-linear model of aircraft with uncertain parameters is a novel contribution which could be further used for the unmanned aerial vehicles autopilot, flight trajectory tracking and path following.

Robust Output Feedback Control of Single-Link Flexible-Joint Robot Manipulator with Matched Disturbances Using High Gain Observer

“…Note that at least measurement of one state using sensor or knowledge of initial conditions of the system is compulsory to design an observer. In practical scenario, it is difficult to measurement all the state variables, or even sometimes not feasible, because of technical or economic reasons as sensors are needed for each state of the systems [ 40 , 41 ]. To address this drawback, OFC can be designed that measures output of the systems whereas for estimation of unknown remaining states an observer is used.…”

Robust Composite-Disturbance Observer Based Flight Control of Quadrotor Attitude

“…For solving the drawbacks of SFC algorithms, output-feedback control (OFC) schemes have been developed. In [10], an OFC based on robust control technology was developed for the UAV aircraft. However, the controller required the tunning of the control parameters for achieving the desired control performance.…”

Part 1: robust adaptive control of quadrotor with disturbance observer

“…In addition, backstepping control method was not robust, and the NDI method faced the problem of singularity. To investigate the nonlinear method based on feedback-linearized system, the control method was developed by Raza et al (2020) and Voos (2009). Moreover, hybrid control methods by combining multiple linear and nonlinear control methods are also investigated by researchers.…”

“…However, there are still research gaps to improve the control systems even further. According to recent trends in research of automatic control, unmanned aerial vehicles (UAVs) are getting major highlights because of its maneuverability, low-cost operation and ability to fly without an on-board pilot (Raza et al , 2020). Therefore, in this paper, a UAV quadrotor is chosen for the control design.…”