Research On The Application Of Tilt RTK Attitude Calculation Algorithm

The booming semiconductor industry has led to a wide range of applications of attitude measurement technology in defense and military,industrial control,and civilian consumer electronics.Among them,the attitude measurement based on Micro-electromechanical Systems(MEMS)sensor is initially used in tilt RTK with the advantages of low cost,low power consumption and light weight.However,due to the low accuracy of consumer-grade MEMS sensors,the attitude angle solved by the traditional attitude solving algorithm has a large error and is prone to angular drift,which causes the deviation of the measured coordinates in the tilt RTK.In order to solve this problem,this paper is based on the comparative analysis of Euler’s angle method,direction cosine method and quadratic method,and the problems of attitude angle drift,large solution error and weak adaptive adjustment ability are investigated.(1)To address the problem of serious angular drift in the measurement system.In this paper,starting from the working principle of sensors,filter,calibrate and calibrate the measurement information of gyroscope,accelerometer and magnetometer respectively,establish the sensor determination error model and design different error parameter calibration methods to ensure the reliability of the output data source accuracy.(2)In order to solve the problem of delay and error of single sensor in attitude measurement system,this paper uses mahony complementary filter and extended Kalman filter combined with quaternion to realize the fusion of measurement information.The mahony complementary filter fuses the accelerometer and magnetometer information and obtains the angular velocity compensation amount through the conversion fork multiplication of coordinate system,and adjusts the compensation weight using PI controller.(3)To address the problem that the PI controller parameters in the mahony complementary filtering algorithm cannot be determined and the adaptive adjustment capability is weak.In this paper,we propose a correction scheme based on the differential evolution algorithm to compensate the PI controller in mahony by using the adaptive global optimization seeking feature possessed by the intelligent optimization algorithm.The method can accomplish adaptive tuning in different environments,has strong stability and fast convergence speed,and can solve the problem of complex PI controller parameters.In the static experiment of the equipped total station platform,the DE-mahony complementary filtering three-axis attitude error can be controlled within 0.1°,which improves the three-axis accuracy by 14.2%,42.9% and 58.5% respectively compared with the unmodulated mahony complementary filtering algorithm.In the dynamic test,the root-meansquare error of the proposed algorithm is within 0.3°,and the accuracy of the drift-prone heading angle is 25.4% and 30% higher than that of the EKF and mahony algorithms,respectively.The experimental results show that the algorithm proposed in this paper shows good results for the problems of serious angular drift,difficult adjustment of PI controller parameters,weak anti-interference ability and low decompression accuracy in attitude solving,which has certain engineering use value for improving the performance of low-cost MEMS sensors and ensuring the stability of tilt RTK attitude control system.