Research On Active Robust Control Technology Of Unmanned Aerial Vehicle Under Limited Measurement Capability

In recent years,unmanned aerial vehicles have been widely applied in various fields.Compared with the traditional manned aircraft,UAV has the advantages of small size,easy to use and strong maneuverability.However,due to the problems of size and load,UAV can not meet the high robustness requirements under many application scenarios.Therefore,this thesis mainly aims at the theoretical deduction,simulation and experimental verification of the control problem of the small quadrotors,and improves and consummates the existing UAV control system so that it has better robust performance.The main contents are as follows:Based on the analysis of the common quadrotor control process,the flight control system is divided into two parts: inner-loop control and outer-loop control.In the innerloop control,the PID controller based on the standard integral,the PID controller based on bounded integral and the robust controller based on the UDE interference estimator are designed for the finite conditions of the model uncertainty,the input integral saturation and the existence of unmeasurable interference.According to the working principle and mechanical analysis of the quadrotor aircraft,the kinematic model of the ideal state is set up,and the MATLAB/Simulink simulation program is set up to verify the effectiveness of each controller.The quadrotor physics experiment platform and the 3-DOF helicopter simulation platform is built,and the robustness of the algorithm is verified by flight experiments.In the outer-loop control,the robust performance of the outer-loop controller is verified by the flight test,aiming at the lack of necessary data information and so on.By using the vision based motion capture system to provide the unmanned aerial vehicle with the corresponding measurement data,the outer-loop control system is built for the UAV through the computer.Through the simulation and experimental analysis,under the same experimental conditions,the PID controller based on the standard integral and the PID controller based on bounded integral can keep the UAV stable flight.The bounded integral control with unmeasurable interference has good robust performance.The robust controller based on UDE has strong robustness against non-measurable constant force and variable force disturbance on a 3-DOF helicopter platform.In the case of UAV inner loop control stability,by adding the outer loop control system,the UAV's robust performance can be significantly enhanced.