Data Preprocessing of Magnetic Suspension Gyro-Total-Station by Vondrak Filter

For Magnetic Suspension Gyro-total-station has vulnerable to outside interference factors, there are some random drifting containing in measurements which are unable to establish its mathematical model. Vondrak filter which does not require the model is used to pre-process measurements of Magnetic Suspension Gyro-total-station. In this paper a high-precision astronomical baseline is established in Xi'an, and the gyro azimuth is tested eight times in baseline. 40,000 north-seeking torque of the first and second place is filtered by the Vondrak filter for each test. The results show that the burr of data is reduced after filtered, and the filtered values reflect the trends of gyro north-seeking. Compared with the root mean square (RMS) of the measurements, RMS of Vondrak filter is decreased, the data is denser. Vondrak filter can effectively eliminate the random drifting containing in measurements, retain useful information in the maximum extent, and improve the accuracy of true north azimuth.