指定性能指标的运载火箭姿控系统设计

To solve the problem that the attitude tracking control performance of launch vehicle is easy to be affected by parameters and uncertain, a controller is designed whose control performance indicators (overshoot, response time and tracking error convergence time, etc.) can be predefined in advance. Firstly, dynamic model of attitude tracking error is established based on the second-order system reference model and the dynamic equation of the launch vehicle. Then, a new type of Lyapunov function inequality theorem including the appointed time convergence is constructed. Based on the tracking error dynamic model, the attitude tracking control law with appointed time convergence is deduced by the backstepping method, and the convergence time can be preset as the parameter of the controller. Stability of the controller is further proved by Lyapunov method. Finally, a simulink simulation framework is built for the attitude control system of the launch vehicle. Compared with the conventional sliding mode controller and PID controller, the designed controller can track the reference model within the appointed time and achieve the predefined performance, and the steady-state error of the three channels is less than 10^-6 degrees.