A Small UAV Quadcopter

With the rapid development of computer science and automation technology, the research and application of the intelligent robot gradually become the focus of academic groups and research institutes. Quadcopter as a member in the research field of intelligent robotics, involving many fields of high, refined, sharp technology, and with the advantages of its novel structure and the flexible maneuverability, has been more and more attention in many fields such as national defense field, commercial field and civil field.Based on the research of the status, trend and application prospect of quadcopter at home and abroad, this paper designs a small quadcopter which can meet the demand of basic flight movement. By studying the structure, working principle, the attitude estimation and attitude control process of the quadcopter, we design a flight control system which is used the Stm32 as the core and MPU6050 as the inertial measurement unit. Quadcopter system includes quadcopter,handheld remote controller and Upper machine. MPU6050 sensor is integrating three-axis gyroscope and three-axis accelerometer sensors. Stm32 collects angular velocity and acceleration measurement values from MPU6050 for data fusion and estimate the current attitude. According to the movment from handheld remote control, calculate the target attitude. Therefore, we get the attitude error. We put the attitude error into the PID feedback system to calculate the throttle of the four motors. Through the throttle of the four motors adjust the current attitude to the target attitude to implement all kinds of complicated movement. The upper machine can display the 3D attitude of the quadcopter through receive the attitude datas form the quadcopter. At the same time, the quadcpter can change the parameter by the upper machine, and this is very convenient in the debugging process.At the end of the paper, we analyze the attitude estimate algorithm based on quaternion, and the static error less than 0.945°verify the feasibility of the attitude estimate. And a stable fly verify the feasibility of the attitude control. Therefore, the design of quadcopter in this paper laid a certain foundation for the future more powerful quadcopter.