ERG-based Constrained Nonlinear System And Its Application In Angle Of Attack Control

This thesis takes the aircraft limitation of the angle of attack of as the research background.It mainly studies how to give a reasonable threshold of the Lyapunov function and how to adjust the gain parameter κ in the design of the constrained nonlinear control system based on ERG.The calculation of the Lyapunov function threshold is analyzed from the perspective of the phase plane(phase space),and the existing design of the Lyapunov function threshold is verified.The influence of the gain parameter κselection on the ERG constrained nonlinear control system is discussed in this thesis.Two algorithms for automatic adjustment of the gain parameter κ based on the genetic algorithm and the DDPG(Deep Deterministic Policy Gradient)algorithm are presented respectively.This thesis verifies the applicability and effectiveness of the ERG control framework in aircraft angle of attack control,and also provides a reference solution for other constrained nonlinear problems,such as the anti-rollover problem in vehicle handling and stability control.The main work of this thesis is as follows:Firstly,the constrained nonlinear problem based on ERG is decoupled into two parts:the pre-stabilization system and the reference calculation.The dynamic safety margin is calculated by the Lyapunov-based approach.The aircraft pitch modeling and the aircraft pitch modeling considering the attitude angular rate with the attack limit as the background are given respectively.Secondly,the design of the ERG controller for the aircraft pitch model is given.According to the aircraft pitch model,the Lyapunov function threshold used to calculate the dynamic safety margin is given.From the perspective of the phase plane,the Lyapunov function threshold calculation is analyzed to verify the threshold.The ERG controller gain parameter κ of the aircraft pitch model is discussed.The simulation results of the aircraft pitch model added the ERG controller is given.Then,the design of the ERG controller of the aircraft pitch model considering the attitude angular rate is given.According to the aircraft pitch model considering the attitude angular rate,a Lyapunov function threshold for calculating the dynamic safety margin is given.From the perspective of the three-dimensional phase space,the Lyapunov function threshold calculation is analyzed to verify the threshold.The ERG controller gain parameter κ of the aircraft pitch model considering the attitude angular rate is discussed.The simulation results of the aircraft pitch model considering the attitude angular rate added the ERG controller is given.Finally,the algorithm based on genetic algorithm and the algorithm based on DDPG algorithm to automatically adjust the ERG controller gain parameter are given The aircraft pitch modeling and the aircraft pitch modeling considering the attitude angular rate with the attack limit as the background are given respectively and the simulation results are given.