1. Wuhan University of Technology, Wuhan, Hubei 430070, China
2. Hubei Instiute of Measurement and Testing, Wuhan, Hubei 430223, China
3. National Institute of Metrology, Beijing 100029, China
Abstract：In order to accurately measure the distance between the center of mass and the optical center of the falling body of the gravimeter, and to reduce the influence of the rotation caused by the non-coincidence of the center of light and the center of mass on the measurement of the acceleration of gravity, a set of spatial distance measurement device for the falling body′s mass center and optical center was built. The calculation method of the distance between the optical center and the center of mass was proposed, and the feasibility of the scheme was verified through simulation. Test the falling body with the measuring device and numerical analysis shows that the measurement accuracy of the laser interferometer at the signal frequency of 0.3~0.5Hz is 0.1nm. The improved calculation method can make the measurement system′s class A uncertainty better than 10μm and maximum measurement error in adjustment is 1μm.
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2023, Vol. 44 
