Design Of Lateral Thrust And Aerodynamics Blended Control System Based On Auto Disturbance Rejection Controller

With the development of air-attack weapon towards miniaturization and high speed, intercept missile requires higher guidance and control accuracy. Due to the response delay of air rudder, traditional aerodynamics control mode can not meet the precision requirement. So, lateral thrust control is added to aerodynamics control to implement accuracy interception in the situation of high altitude, high speed and high maneuvering target. However, the addition of lateral thrust manipulation mechanism brings many new problems. Thus, it has important academic and engineering significance to investigate the guidance and control methods for a missile with lateral thrust and aerodynamics blended. This dissertation studies the guidance and control problem of blended control system based on auto disturbance rejection controller (ADRC), and the main contributions are the following:Firstly, considering jet interaction and thrust misalignment, the mathematical model of blended control system is established. The aerodynamic configuration and lateral engines layout of blended control missile are confirmed, and the calculating model of force amplification factor is given based on an estimation method. Then the lateral thrust model and thrust misalignment model are established. Based on this, the kinematics and dynamics model of blended control system is derived. These works lay the foundation for further researches.Secondly, ADRC design method is deeply studied. Stability of the second order extended state observer (ESO) is proved by multiple lyapunov functions method, and the error analysis is achieved by the stability condition, also the judging criteria of error convergence for different ESO parameters is given and the value of error convergence is gained. Then, in the light of measurement noise debasing ADRC performance, a new type extended state observer based on fal function feedback structure filtering is proposed, which can deal with nonlinear system with measurement noise effectively. Moreover, fuzzy ADRC is proposed to enhance adaptability of ADRC, then a system with large disturbance is designed by this method, and the stability of designed system is analyzed.Thirdly, the attitude control design method of blended control system is studied by ADRC. In the light of nonlinear and coupling being large in vertical launching phase, the attitude angle tracking loop is designed by combined control strategy of fuzzy ADRC and NLSEF, which can simultaneously implement rotation and rolling. In the light of large disturbance of blended control system in terminal guidance phase, the overload tracking loop is designed by combined control strategy of fuzzy ADRC and PI, which can track overload command with high precision and fast response speed, and the controller has excellent robustness performance. In the end, the stability of designed close-loop attitude loop and overload loop is analyzed by ESO stability theory.Fourthly, the guidance law design method of blended control system is studied by ADRC. A terminal guidance strategy is proposed based on ADRC and predictive miss distance, which can solve the problem of lateral engines igniting once. ADRC guidance law is designed, and a target acceleration estimation method based on ESO is proposed. According to the value of target acceleration estimation, predictive non-zero effort miss distance can be achieved. Then the predictive miss distance compensation method is proposed, and the ignition command of lateral thrust can be gained. The simulation results show that the proposed guidance method is applicable to the guidance system of lateral thrust and aerodynamics blended, which can reach high guidance accuracy.Finally, the comprehensive design of guidance and control law for a certain endo-atmosphere interceptor is studied. According to given system parameters and performance requirements, the amplitude of disturbing moment is confirmed, and the parameter tuning is done, moreover the attitude control law is designed. In the light of the uncertainty of seeker measurement information, the guidance law is designed, and the stability of guidance and control system is analyzed. Based on this, the validity of proposed methods is proved by six degree of freedom simulation, and the simulation results show that designed blended control system reach high guidance and control accuracy, and it has relatively strong ability of noise suppression, anti-disturbance and robustness.