The Research Ofcontrol Algorithm For Quadrotor Unmanned Aerial Vehicle

The Quadrotor UAV has much advantage in vertical rising and landing with a simple mechanical structure.So recently years many labs spend much on its research.Its covers a number of cross-integration of advanced subject,such as Manufacturing Technology,Structural Design,Materials Engineering,Aerodynamics,Autonomous Flight Control,Advanced Communication Technology,Energy Efficiency,MEMS Technology.This research of control algorithm for quadrotor sets the base for advantage in applying.In this article,our mainly job is to research the control algorithm for the aircraft.The research is outlined as follows:Quadrotor modeling: Based on the aerodynamic knowledge and mechanical structure,the thesis study force analysis and then deduces mathematical model by the Newton-Euler theorem.The quadrotor has underactuated,multivariable,strongly coupled,nonlinear characteristics.The thesis then introduces main prime hardware and theorem of control.Attitude estimation with quaternion algebra: This paper draws a conclusion for attitude estimation with the method of quaternion algebra.By introducing two kinds of coordinate system that is ground and flight system,we get the transformation matrix between the two of t coordinate systems with method of quaternion algebra.The matrix lays a foundation for control algorithm.The control strategy based on the PID: Firstly,this thesis discusses the coupling relationship between angular control and horizontal position.The total algorithm is designed by dividing it into two parts,that is inner loop control and outer loop control,which is also called angular control and horizontal position control.Then the simulation verifies this control method.The control strategy of quadrotor based on backstepping: Firstly,this thesis introduces the base for the method backstepping---Lyapunov stability criteria,and then deduce the strategy with backstepping and state-space equation of the quadrotor.Furthermore,simulation by Matlab shows that backstepping strategy performs much better than PID strategy.The control strategy of quadrotor based on adaptive backstepping: in order to simulate real flight environment,disturb is took into account in the control system.The strategy introduces an error estimator and deduces all the control equation for every state variable.The simulation shows that the strategy has a good stability and robustness.