Research On Trajectory Planning And Tracking For Micro Quadrotor UAVs

The micro quadrotor unmanned air vehicle(UAV)is a kind of aircraft with diverse flight mode,simple structure,high mobility and flexibility.It is widely used in various fields such as aerial photography,plant protection,industrial inspection,unmanned reconnaissance etc.In order to perform the flight mission micro quadrotor UAV is very dependent on the trajectory planning,and it has the own characteristics of underactuation,strong coupling and nonlinearity.So the reasonable path planning method and reliable flight control algorithms are of great significance to improve the intelligent degree and flight stability of quadrotors.This paper focuses on the analysis and research of the trajectory planning and tracking of micro quadrotors.The main research work is as follows:Firstly,the flight principle of the micro quadrotor UAV is analyzed in detail.The navigation coordinate system and body axis system for describing the position and attitude of the UAV are introduced,and the conversion relation between two coordinate systems is derived by Euler angle method.Based on the Newton and Euler equations,the dynamic model of quadrotors is derived.Secondly,the principles of dynamic movement primitives(DMPs)are described.The movement learning framework is introduced,and it could be applied to the trajectory planning of micro quadrotors.Given the learning of movement samples,the movement primitives were extracted.The learning results can also be generalized to new flying targets to generate corresponding trajectories.Under the circumstance of obstacles on the path of the new flight,the avoidance path can be produced through designing coupling factor.The simulation results show that the four-rotor trajectory planning based on DMPs is feasible.Thirdly,the trajectory tracking controller of the quadrotor UAV is designed by using backstepping method,which includes the design of the horizontal underactuated channel controller and the altitude-heading direct channel controller.Through the simulations of the fixed point hovering,the arc,the rectangular trajectory and the trajectory based on the DMPs planning given to UAVs verifies that the quadrotor can stably track the given trajectory under the designed control.Finally,aiming at the problem of state estimation in the micro quadrotor UAV,the calibration method of gyroscope accelerometer and magnetometer,and the low-pass filtering method of accelerometer are given.The complementary filter is applied for attitude estimation of quadrotors and the height estimation of quadrotors is carried out by using Kalman filter.The effectiveness of the above methods is verified by experiments.