Trajectory Planning And Control For Quadrotor Via Aerodynamic Compensation

Recent years,the quadrotor has developed rapidly.It has the characteristics of flexibility and can be controlled easily,it can take off and land vertically,hover at a certain point and can fly forward and backward,left and right,up and down,and yaw freely.At the same time,its size can be made very small which means it can be used in the restricted space.Therefore,the quadrotor has been paid much more attention and used widely in the fields of military,aerial photography,geographical survey and so on.However,the quadrotor system is a typical under-actuated system and is vulnerable to interference from external uncertainties,which makes the research on the quadrotor full of challenges.This thesis introduces the development background and research significance of the quadrotor,including the research on the controller design and trajectory planning algorithm of the quadrotor,and analyzes the current research direction and challenges in the field of the quadrotor.On this basis,the dynamics modeling,flight controller designing and flight trajectory planning of the quadrotor are studied in this thesis,and make the quadrotor accurately track an aggressive trajectory and safely fly through an inclined narrow gap.This thesis takes the micro quadrotor as the research platform,analyzes the structural characteristics of the flight principles of the quadrotor.The mathematical model of the quadrotor is established according to the Newton-Euler formula.Aiming at the problem that the accuracy of the mathematical model may affect the control effect of the controller,this thesis studies the effects of aerodynamics on the quadrotor and establish the aerodynamic disturbance model for the quadrotor based on the traditional quadrotor's mathematical model.The aerodynamic disturbance model,of which parameters can be identified through experiments,is introduced into quadrotor's dynamical model to establish a more accurate mathematical model of the quadrotor.For the quadrotor's flight controller,this thesis studies the cascade PID controller and the controller based on the differential flatness algorithm,and performs aerodynamic compensation in the design of the controller based on the differential flatness theory.Under the MATLAB/Simulink simulation environment,the performance of the two controllers are compared and analyzed.For the aggressive trajectory planning problem,this thesis uses the properties of differential flatness algorithm and minimum snap trajectory planning method to generate an aggressive trajectory through an inclined narrow gap,and combines with the differential flatness based controller,the performance of the algorithm in the simulation and experiments are verified and analyzed,respectively.