Data Processing Analysis Of GAT Maglev Gyroscope Total Station Based On Hilbert-Huang Transform

With the continuous development of Surveying Engineering technology,the requirement of instrument accuracy is also increasing.GAT Magnetically Suspended Gyroscope Total Station is a new generation gyroscope developed by Chang'an University and China Aerospace Institute in 2008.It not only integrates gyroscope and total station,makes angle and side length measurements at the same time,provides convenience for underground engineering survey,but also replaces traditional suspension support technology with magnetic suspension technology.The innovation of this technology is extending the gyroscope.At the same time,the service life of the instrument also reduces the maintenance cost caused by the internal loss of the instrument.The results of north-seeking orientation of GAT Maglev Gyro Total Station are mainly calculated from stator current data and rotor current data.In order to improve the accuracy of north-seeking,we need to ensure the quality of stator current and rotor current data.Based on previous studies,stator current data and rotor current data measured by the instrument contain a large number of high-frequency noise effects.In order to eliminate or reduce the interference of noise on data,this paper uses Hilbert-Huang transform to process and analyze the data.The main research contents include data de-noising and time-frequency spectrum analysis before and after processing.EMD method is mainly used to denoise stator current and rotor current data.Because of the effect of end-point effect and mode aliasing in the process of EMD decomposition,we adopt the methods of end-point continuation and ensemble empirical mode decomposition to process the data separately,and then use correlation coefficient method to extract the effective components from EMD,eliminate the components containing a lot of noise interference,and process the remaining ones.Effective components are reconstructed,and the reconstructed data and the northward deviation angle calculated from the original data are compared and analyzed with the true value.Through the comparative analysis of examples,it can be seen that the accuracy of the data has been improved to a certain extent.The time-frequency spectrum analysis mainly uses the effective component spectrum analysis and the original component spectrum analysis after decomposition to compare.After the result analysis,the component we extracted is more ideal.