QU Xin-Xin,
LI Tong-Lin,
WANG Fei
.2014.A study on the effect of bird’s attitude on helicopter EM data and the correction method.Chinese Journal Of Geophysics,57(4): 1310-1321,doi: 10.6038/cjg20140428
直升机吊舱姿态变化对电磁场测量的影响规律及其校正方法研究
曲昕馨, 李桐林, 王飞
吉林大学地球探测科学与技术学院, 长春 130026
A study on the effect of bird’s attitude on helicopter EM data and the correction method
QU Xin-Xin, LI Tong-Lin, WANG Fei
College of Geo-exploration Science & Technology, Jilin University, Changchun 130026, China
The attitude changes of the bird can influence both the direction and position of the magnetic dipole which may introduce errors into helicopter electromagnetic (EM) data. The traditional attitude correction methods using a superposed dipole model only consider the change of direction but ignore the position variation, so limit correction effects. We employ five models with different electrical parameters and calculated the EM response ratios before and after attitude change. We further propose a new attitude correction method which takes both the changes of direction and position before and after attitude change into account. We deduce an approximately constant relationship between the EM response ratio of the total attitude effect and the product of the EM response ratios when the direction effect and position changes separately. In order to test the new total attitude correction method, this paper employ five sets of synthetic data for correction using the superposed dipole correction method and our scheme, respectively. The comparison indicates that the total attitude correction method suggested in this paper is able to generate a better correction result than the superposed dipole method.
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