The Research Of Navigation And Control System Of Quadrotor

Quadrotor is a new model of small Unmanned Aerial Vehicles that could take-offand land vertically. It has four propellers with a Symmetric cross structure. Thequadrotor has some dynamic features such as high coupling degree, non linearity, time-varying and the uncertainty of the system itself. It adjusts its position and attitude byvarying four symmetrical propellers’ speed, with the merits such as hovering ability,good maneuverability, and simplified structure. Quadrotor attract national science andtechnology workers’ s attention.This paper takes quadrotor Unmanned Aerial Vehicle as the object of the research.First, the article has analyzed the flying principle of quadrotor and proposed overalldesign solution. Characteristics of aerodynamics and kinematics of the quadrotoraircraft are analyzed, the linear mathematical model and LPV model were established,taking it as the control system of simulation model.Second, due to the demands of quadrotor on navigation information, this paperdesigned an attitude and heading reference system based on STM32micro controller,gyroscopes, accelerators and magnetic sensors, and based on quaternion extend kalmanfilter’s Navigation algorithm was designed. In this filter, the quaternion, gyroscope’szero drift were chosen as state variables, gyros were used to update the stats variables,and accelerators and magnetic sensors were combined to establish measurementequation. Then the flight attitude and heading information was obtained. The paper hasachieved a complete design of a miniature embedded navigation application platform, tosend the data to PC with the way of wireless Zigbee serial port module. Data curveshown and saved in the LabVIEW, and the sensor data fusion effect was analyzed.Experiment results demonstrated that this type of algorithm was effective in attitudeestimation state. Experiment results demonstrated that this type of algorithm waseffective in attitude estimation. And better dynamic performance needs to improve navigation algorithm in further tests, thus providing accurate heading attitude and foraircraft stable flying.According to the selected position sensorless BLDCM, a speed control system wasdesigned. In the design of speed control system, back-EMF zero-crossing detectionprinciple was used to detect the position of rotor. And the principle of PWM speedcontrol also was adopted to achieve the motor starting, running and speeding up as wellas the speed adjustment successfully.Quadrotor has the characteristics such as nonlinear, uncertainty, coupling and so on,the paper finally research control algorithm for the quadrotor aircraft system simulationmodel in Matlab. Considering the nonlinear model of the system, PID control was usedfor pitch, roll, yaw and vertical speed, the simulation results of the system wasanalyzed，the control algorithm was verified of deffectiveness.