Design And Implement Of Four-rotor Aircraft Control System

The development of Micro quadrotor has become a reachable dream thanks to progress in sensor technology,data processing and integrated actuator.Micro VTOL systems have a great advantage of small-aero monitoring,building exploration and intervention in dangerous environments.The quadrotor is a under-actuated,strongly coupled,nonlinear system.It has been a hot field to research in recent years.Thesis completes the following aspects:Firstly,the paper presents some typical articles in the quadrotor at home and abroad.It shows some project in the research institution,together with some difficulties and dicrections of quadrotor.Six degrees of freedom underactuated quadrotor motion dynamic mathematical model is established after a reasonable simplification.We also makes some analysis of the quadrotor in theory,at the same time neglects some effects of air factor.Secondly,the hardware platform for quadrotor is established in this paper.The ST company’s Microcontroller STM32F103 was chosen as the main controller and some sensors including accelerometer&&gyroscopes MPU6050,electronic compass HMC5883,barometer MS5611 were selected as measurement equipment.The main controller is used to read the attitude information and run the control algorithm.The plateform is used to verify the feasibility and availability of the designed control algorithm.Thirdly,we introduce the whole software design of the quad-rotor detailedly.Including the initialization of all the electronic equipments and reading the data from the sensor,then we designed a fusion algorithm to get the attitude of the quadrotor based on quaternion and kalman filter.At last we fulfilled the PID control algorithm in the platform we designed.Fourthly,in this paper,A classical control strategy was applied on the Mini quadrotor,Two-layer control structure were designed in order to keep the stabilization of quadrotor.The inner-loop controller is responsible to the angular and outer-loop controller is responsible for the position control.It is proved that the two subsystems is Lyapunov stable by the control laws.At the same time,a classical controller was designed for the system of quadrotor.Finally,A test of the designed quadrotor’s hardware,hovering test were carried out in an open laboratory,the result proves that the designed platform work well and the flight controller has a stable control over the quadrotor’s attitude.At the same time,it figures out the shortcoming and weakness during the whole designed process,and gives the improvement for the future work.