Experimental analysis of the performance of a new shipboard gravity gradient measurement system

Abstract

The gravity gradient tensor, which has a higher resolution than gravity, is used in a variety of fields, including the discovery of energy resources, auxiliary navigation, and national defense building. Our team has achieved significant advancements in various essential technologies, such as high-resolution accelerometers, and has constructed China’s first self-controllable shipboard gravity gradient measurement system. In the laboratory, accuracy is determined using the mass gravitation technique, static test accuracy of Tuv and Txy is 7.22 E and 3.58 E, while dynamic test accuracy of Tuv and Txy is 9.09 E and 4.16 E. For outfield shipborne test measurement, the internal accord accuracy of Tuv and Txy of the repeat line is 28.2E@750m and 28.8E@750m, and that of the intersection point is 28.2E@750m and 26.8E@750m. The performance of the system is completely validated by dynamic and static testing, laying the groundwork for the practical implementation of gravity gradient technology.

Error analysis of calibration for horizontal tensor rotating accelerometer gravity gradiometer

“…The Tianjin Navigation Instrument Research Institute successfully developed high-resolution quartz flexible accelerometers that were specifically designed for a RAGG with a noise floor of 1 ng/√Hz (1 g ≈ 9.8 m s −2 ) and nearly 10 E/√Hz by converting a RAGG (the baseline radius of the RAGG is 0.3 m). This RAGG achieved a 40 E resolution level [7], and shipborne tests have been attempted [8]. In the development of high-precision accelerometers in other types, Williams et al [9] utilized the diffraction grating principle to create an optical-based accelerometer, this accelerometer achieved a noise floor of 3 ng/√Hz within a bandwidth of 0.1-100 Hz.…”

“…Deng et al [20] used a manual method of moving lead columns to generate gravity gradients and performed calibration on the RAGG. However, due to errors in manual operation, the positioning error can reach a maximum of 39 E. Li et al [8] used two highdensity mass walls to induce changes in gravity gradients for performance testing of the RAGG. Yu and Cai [18] proposed a method to indirectly calibrate RAGG by exciting centripetal gradients.…”