Uav Nonlinear Attitude Control Law Design And Simulation

Automatic flight control system is the core on UAV, the flight performance of UAV depends on the quality of designed flight control law to a great extent. Therefore, it has great significance to research automatic flight control system.The research target is the UAV with normal pneumatic layout. Firstly, Aircraft's kinematics equations are set up and dynamic equations are obtained by transformation of coordinates. So, six degree of freedom,nonlinear mathematic model is derived. Simulink models are built in combination with Aerosim toolbox, which include force equations,kinematics equations,moment equations and navigations equations. On a basis of this, from the view of engineering application, the application of PID control on UAV are analysised. The simulation with attitude as input is made and the results of simulation show that overshoot is larger and response time is longer. At the same time, the parameters of PID need to adjust according to different states, therefore, the process is complicated.Aiming at the above research result, and referencing the experience of successfully applicating dynamic inversion control on manned aerial vehicle, flight control law is designed by applicating dynamic inversion. According to singular perturbation theory, the inner/outer loop controllers are designed for the fast and slow variables respectively. The simulation's results show that the control law achieves a high level of performance, which is combined with aerosonde's pneumatic parameters. But the dynamic inversion control needs accurate model, and its robust performance isn't good.In order to improve the control performance, the methods of nonlinear dynamic inversion and robust PID control are combined. A new scheme of the inner/outer dynamic inversion control law is put forward, which get rid of the two methods' shortage. The simulation results show that the result of control demand the requirement of flight quality.Lastly, based on VR toolbox in Matlab and use the V-Realm Builder2.0, virtual reality flight simulation system is set up; 3-D cartoon technology of computer is applied on experiment field, interactive visualization environment is built to realize attitude simulation of UAV.