Accuracy Test of the Absolute Gravimeter FG5X-246
Jingang Zhan, Yong Wang, Bai Lei, ZHANG Erlin, YAO Yixin · DOAJ (DOAJ: Directory of Open Access Journals) · 2017
The observation accuracy of the absolute gravimeter FG5X-246 is tested by using the weak force test platform. The disturbing gravity field, which is produced by changing the distance between the disturbing mass and the observation point, can be superposed on the background gravity field directly. It is measured that this gravity change using FG5X-246 absolute gravimeter and compared it with that of theoretical disturbing gravity field and then determined the accuracy of the absolute gravity observations. The test results show that when the height of the disturbing mass changes from 1.810 4 m to 1.409 9 m, the disturbing gravity field changes for 48.81 μGal (1 Gal=1 cm/s2), while FG5X-246 absolute gravimeter senses the gravity change of 48.0 μGal, and the difference between the measurement value and the theoretical value is 0.81 μGal. When the height changes from 1.810 4 m to 1.010 1 m, the disturbing gravity field changes for -15.44 μGal, while FG5X-246 absolute gravimeter senses the gravity change of -16.20 μGal, the difference of them is 0.76 μGal. When the height changes from 1.409 9 m to 1.010 1 m, the disturbing gravity field changes for-64.20 μGal, while FG5X-246 absolute gravimeter senses the gravity change of -64.25 μGal, the difference of them is 0.05 μGal.The results indicate that the FG5X-246 absolute gravimeter sensing external gravity change error is no more than 1 μGal, that is, the accuracy of the measured value is better than 1 μGal.