Research On Key Technology Of Multi-rotor Unmanned Aerial Vehicles

Multi-rotor UAV has been widely attention of the society in recent years,because it has the advantages of flexibility,the vertical take-off and landing etc.. This paper studies on the key technologies of multi-rotor UAV which is constituted by Multi-rotor and coaxial rotor,from the point of engineering application. Then we design the structure and control system of the multi-rotor UAV with this configuration. Specifically,the main contents of this paper include the following aspects.(1) Multi-rotor UAV development status and background are studied,the purpose of the study is also described clearly. This paper describes the control principle of multi-rotor UAV. The dynamic model of multi-rotor UAV is established,based on the Newton’s second law and the law of rigid rotation. And we analyzes the movement mechanism of coaxial rotor.(2) We propose a method for testing the lift of coaxial rotor, and design the test platform using Solidworks software. Then we anlyze the static strength of the platform,and complete the test.(3) Using Solidworks software designs a gear, based on the analysis of the transmission principle of the coaxial rotor. The device can transmit the constant and reverse speed to the dual rotors. We also design an multi-rotor which is constituted by Multi-rotor and coaxial rotor,then the aircraft is studied about static analysis and modal analysis by ANSYS Workbench which is a finite element analysis software.(4) The dynamic equations of multi-rotor UAV are simplified.We design the PID controller by MATLAB/Simulink,and set up the Simulink block diagram of each module,the step response curve of roll,pitch,yaw and height are got. At last,we compared the change of multi-rotor UAV’s attitude and height response before joining the coaxial rotor force and after.