The Hardware Platform And Underlying Software Design Of The Four-rotor UAV Flight Control System

The four-rotor UAV has the advantages of small size,strong maneuverability,simple structure and stable operation.Whether in military or civilian use,it has a wide range of applications.With the continuous development of microprocessor technology and control technology,quadrotor drones are constantly updated and upgraded,which has attracted more and more researchers’ attention.The research goal of this paper is to design and develop a flight platform for a quad-rotor UAV that can operate stably.This article first studies the flight principles of quadrotor UAVs.After analyzing the flight principle and mechanical characteristics,the dynamic model of the UAV flight control system was developed based on Newtonian mechanics.A PID controller is designed according to this model,and Simulink tool is used to simulate and verify the performance of the controller.Finally,the basic principles of attitude calculation based on quaternion method and extended Kalman filter are studied.The design of the entire flight control platform is divided into hardware design and software design.The hardware design part is based on the design requirements for the overall design of the flight control system hardware scheme,and at the same time the selection of key chips.Then,based on the modular idea,the flight control system is divided into controller module,sensor module,dual-port RAM module,PWM module,communication module,power module and function expansion module.The hardware circuits are designed for each functional module of the hardware platform of the flight control system.After completing the hardware circuit design according to the above scheme,the board is made and the hardware platform of the flight control system is completed.The software part first introduces the development environment,then designs the sensor data acquisition and processing program,and designs the overall program flow of the flight control system.Finally,based on the idea of componentization,the underlying software program of the flight control system is designed.Completed the design and realization of BMP180 component,MPU9150 component and PWM component.Completed the software design of the flight control system as a whole.Finally,in order to verify the rationality and feasibility of the scheme designed in this paper,experiments and tests were carried out on the flight control system.Using tools such as DC stabilized power supply and oscilloscope to test each functional module of the flight control system,it was verified that each module can work normally.The fixed-point hovering experiment verified that the hardware platform and software system of the quad-rotor flight control system designed in this paper can work stably and meet the design requirements.