A Strategy for the Stability of Flight Control System using Nonlinear Differential Equation

The accuracy and real-time of modern missile flight control system of traditional aerodynamic can not be satisfied. In this paper a new method is presented to improve the accuracy and real-time of missiles under this condition. First of all, a missile sub-channel model of the dynamic equations and steering gear is established, then based on the established model, using PID controller to control steering gear and three channels of missile pitch, yaw, roll respectively which is called missile sub-channel PID control method, and finally making use of MATLAB/Simulink to complete the simulation. Simulation results show that compared with traditional aerodynamic control system, this method can reduce the response time of aerodynamic missile and enhance the stability of the control system obviously.

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Robust dynamic inversion control of flight control system based on L1 adaptive structure

Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University ◽

10.1051/jnwpu/20213950995 ◽

2021 ◽

Vol 39 (5) ◽

pp. 995-1004

Author(s):

Yu LI ◽

Xiaoxiong LIU ◽

Ruichen MING ◽

Shaoshan SUN ◽

Weiguo ZHANG

Keyword(s):

Control System ◽

Flight Control ◽

Dynamic Performance ◽

Dynamic Inversion ◽

Control Law ◽

Flight Control System ◽

Parameter Uncertainties ◽

Strong Robustness ◽

Adaptive Structure ◽

The Stability

Nonlinear Dynamic Inversion(NDI) control has excellent rapidity and decoupling ability, unfortunately it lacks the essential robustness to disturbance. From the perspective of enhancing the robustness, an adaptive NDI method based on L1 adaptive structure is proposed. The L1 adaptive structure is introduced into the NDI control to enhance its robustness, which also guarantees the stability and expected dynamic performance of the system suffering from the disturbance influence. Secondly, the flight control law of the advanced aircraft is designed based on the present method to improve the robustness and fault tolerance of the flight control system. Finally, the effectiveness of the flight control law based on the present approach is verified under the fault disturbance. The results showed that the flight control law based on L1 adaptive NDI has excellent dynamic performance and strong robustness to parameter uncertainties and disturbances.

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LQG-Based Robustifying Flight Control System

Dynamic Systems and Control, Volumes 1 and 2 ◽

10.1115/imece2003-43596 ◽

2003 ◽

Author(s):

D. Griffin ◽

A. G. Kelkar

Keyword(s):

Control System ◽

Flight Control ◽

Controller Design ◽

Second Step ◽

Flight Control System ◽

Robust Controller ◽

Fighter Aircraft ◽

Stability Robustness ◽

Uncertainty Model ◽

The Stability

This paper presents a robust controller design for an automatic flight control system (AFCS) for a fighter aircraft model with eight inputs and seven outputs. The controller is designed based on McFarlane-Glover robustifying technique using a simple baseline LQG design. Controllers designed purely based on traditional LQG techniques are known to have no guaranteed robustness margins. The McFarlane-Glover technique can be used to enhance the stability robustness of the baseline LQG design using a two-step design process. In the first step, an LQG controller is designed which is optimized only for performance without any consideration to robustness. In the second step, the performance optimized LQG design is rendered robust using McFarlane-Glover procedure. The robustifying procedure uses a coprime factor uncertainty model and H∞ optimization. An important advantage of this procedure is that no problem dependent uncertainty modelling or weight selection is required in the second step of the process. The robustifying procedure also yields the quantitative estimate of the robustness.

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A Linear Quadratic Integral Design Approach for the Automatic Control System of a Launch Vehicle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.772.410 ◽

2015 ◽

Vol 772 ◽

pp. 410-417 ◽

Cited By ~ 1

Author(s):

Adrian Mihail Stoica ◽

Cristian Emil Constantinescu ◽

Silvia Nechita

Keyword(s):

Control System ◽

Flight Control ◽

Launch Vehicle ◽

Design Approach ◽

Flight Control System ◽

Linear Quadratic ◽

Atmospheric Disturbances ◽

Modeling Uncertainties ◽

Quadratic Integral ◽

The Stability

This paper presents a design approach for the automatic flight control system of a launch vehicle using a linear quadratic integral technique together with a fixed gain Kalman filter. Its purpose is to analyse the stability and tracking robustness performances of the control system designed via this approach when atmospheric disturbances, modeling uncertainties and structural flexible modes of the launcher are taken into account.

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Design and Verification the Simulation System of UAS Flight Control Considering the Effects of Time Delay

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.278-280.1746 ◽

2013 ◽

Vol 278-280 ◽

pp. 1746-1753

Author(s):

Sheng Yi Yang ◽

Sheng Jing Tang ◽

Chao Liu ◽

Jie Guo

Keyword(s):

Control System ◽

Time Delay ◽

Real Time ◽

Flight Control ◽

Simulation System ◽

Unmanned Aircraft ◽

Flight Control System ◽

The Real ◽

The Stability ◽

Hil Simulation

It had not been explored which real-time magnitude can meet the requirement of the simulation object in computer simulation system. Taking time delay into consideration, the influence of time delay on the stability of the low-altitude and low-speed small Unmanned Aircraft Systems (UAS) flight control system had been analyzed and the real-time magnitude of the miniature hardware-in-loop (HIL) simulation system was determined. Then a miniature HIL simulation system of the UAS flight control system was designed to prove the real-time magnitude feasibility. The result shows the real-time magnitude by time delay analysis can meet the requirements of flight control system.

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The Design and Simulation of Low-Cost and Super-Applicability Flight Control System of Super-Size UAV

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.466-467.1156 ◽

2012 ◽

Vol 466-467 ◽

pp. 1156-1161

Author(s):

Liu Rong ◽

Yu Ping Lu

Keyword(s):

Control System ◽

Flight Control ◽

Low Cost ◽

Control Technique ◽

Flight Control System ◽

Flight Curve ◽

Aerial Vehicle ◽

The Stability ◽

High Flexibility ◽

The Cost

In this paper, considering the stability and robustness of the aircraft, the flight control system is designed following the aspect of high flexibility and low cost. Comparing with the flight control system of super-size high-subsonic Unmanned Aerial Vehicle (UAV) in the world, the system presented in this paper has adopted the inimitable control technique of flying-off course、low-cost combinatorial navigation strategy and the advanced safety scheme, which can guarantee the performance, degrade the cost and extend the airspace and groundspace of the aircraft.Through quite a few simulations, the results show that this system can guarantee the attitude and altitude stable. The error between the flight path and programming path is very small. Flight curve is prefect; and the system performances can be achieved completely.

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Research of Mapping Element Space Method for Uncertain Lurie System Stability Diagnosis

Xibei Gongye Daxue Xuebao/Journal of Northwestern Polytechnical University ◽

10.1051/jnwpu/20193750952 ◽

2019 ◽

Vol 37 (5) ◽

pp. 952-961

Author(s):

Weijun Hu ◽

Yiming Ma ◽

Jun Zhou

Keyword(s):

Control System ◽

Stability Analysis ◽

Flight Control ◽

Time Series Data ◽

System Stability ◽

Series Data ◽

Discrete Equation ◽

Linear Matrix ◽

Flight Control System ◽

The Stability

A new diagnosis method of Lurie system stability by using Chaotic time series data was proposed in order to solve stability analysis of flight control system with fault and uncertain. Firstly, the reasons for the instability of the nonlinear system of Ruri leaf was analyzed by using the small gain theory and linear matrix inequalities in the robust control theory. And the stability conditions of Rui leaf system under the condition of uncertainty and failure were proved theoretically. In order to quantify the stability of nonlinear systems in complex Ruri leaves, based on the theory of phase space reconstruction, the nonlinear Ruri system with continuous discrete characteristics was converted into an approximate time discrete equation, mapping it to a low dimensional primitive space, by introducing Q Gauss function into Kernel function, the generalization ability of neural networks are enhanced, realizing the stability analysis method based on the characteristic of primitive migration, which is suitable for various fault and uncertainty conditions, and the relative quantized stability norm can be given. The simulation shows that the present method can effectively solve the stability analysis and determination of flight control system under various factors.

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