Research On Maneuver Control Algorithm Of Quad-rotor Unmanned Aerial Vehicle

Due to its novel appearance, reasonable structure, outstanding maneuverability,relatively low cost and high reliability, quad-rotor Unmanned Aerial Vehicle(UAV) has been chosen to conduct diverse tasks including aerial photography, transportation and agriculture. And it becomes a focus of research in academia gradually. The flight control system is a typical under-actuated multi-input and multi-output system which has some unexpected dynamic features such as nonlinearity and high coupling degree. Using appropriate control algorithm is the key to ensure the good performance of the quad-rotor UAV.Firstly, components and principles of quad-rotor UAV are analyzed. The mathematical model of quad-rotor UAV is built on the basis of its dynamic characteristic. And the LPV law is used to linearization the dynamics model of UAV. The linearized dynamic model of UAV is a first-order lag plus integrator plus delay(FOLIPD) processes with low gain.A new control algorithm, which is called the scorpion algorithm, is proposed to solve the control problem of FOLIPD processes with input saturation. And the engineering scorpion algorithm(ESA) is proposed to achieve the scorpion algorithm application in practical engineering. The stability condition is obtained by means of the describing function method. The genetic algorithm(GA) approach is used to find the best values of ESA’s parameters by minimizing the ITAE criterion. Further, the ESA tuning rules are fitted through the regression analysis. It is demonstrated to be effective in a quad-rotor UAV system.Secondly, based on the nonlinear mathematical model of quad-rotor UAV, the control system is decomposed into attitude control and position control. Attitude controller is designed by using the Backstepping algorithm. The maneuvering performance of the quad-rotor UAV is analyzed, and tracking strategies are proposed for the maneuvering trajectory of the straight line and spiral line. The results are compared with the design of the position controller using the PID algorithm and the scorpion algorithm.Finally, the overall control scheme of the four rotor landing system is proposed, and the APM source code is analyzed and studied. The communication connection between thequad-rotor UAV and the upper computer is realized, which lays the foundation for the further research and design.