Research On Attitude Estimation And Control System Of Quadrotor Based On MEMS

With the continuous development of Micro-Electro-Mechanical Systems(MEMS)technology,microprocessors and Inertial Measurement Units(IMUs)with the advantages of low cost,small size and strong anti-interference are widely used in quadrotor.Attitude estimation and control system are the core links in the design and application of quadrotor.Firstly,two attitude estimation algorithms are designed based on complementary filter algorithm for different flight states and environments of quadrotor.(1)Attitude estimation algorithm on improved explicit complementary filter is designed for quadrotor in hover or low-speed flight.The algorithm adds a low-pass filter before the acceleration data fusion,and sets the attitude quaternion buffer,which improves the attitude estimation accuracy and reduces the influence of the low-pass filter delay on the real-time performance of the attitude estimation.(2)Attitude estimation based on the fusion algorithm of dynamic weight conjugate gradient and adaptive complementary filter is designed for quadrotor in high speed or strong maneuvering flight.The algorithm adds dynamic weights to the conjugate gradient method to suppress the motion acceleration interference,the attitude quaternion estimated by the accelerometer and the gyroscope are adaptive complementary filtering to eliminate the attitude estimation error caused by the integral drift of the gyroscopeThen,aiming at the problem that the parameters of the quadrotor model are uncertain and the vulnerability to external factors,the Active Disturbance Rejection Control(ADRC)technology is introduced into the attitude control system of the quadrotor,and an angle-angle velocity cascade attitude control system based on PID and Linear Active Disturbance Rejection Control(LADRC)is designed.Finally,the experimental platform of the quadrotor was designed and built.Aiming at the problem that the barometer is susceptible to air disturbance and the accelerometer is sensitive to vibration,a separate flight control module is designed torealize the buffering and anti-wind treatment.Based on the designed experimental platform of the quadrotor,the delay time measurement of the acceleration data was completed.The two attitude estimation algorithms designed in this paper were compared with the performance test.The static test,horizontal sliding test and pivoting test were completed.The experimental results show the feasibility and effectiveness of the algorithm.