Scale Factor Calibration for a Rotating Accelerometer Gravity Gradiometer

Abstract

Rotating Accelerometer Gravity Gradiometers (RAGGs) play a significant role in applications such as resource exploration and gravity aided navigation. Scale factor calibration is an essential procedure for RAGG instruments before being used. In this paper, we propose a calibration system for a gravity gradiometer to obtain the scale factor effectively, even when there are mass disturbance surroundings. In this system, four metal spring-based accelerometers with a good consistency are orthogonally assembled onto a rotary table to measure the spatial variation of the gravity gradient. By changing the approaching pattern of the reference gravity gradient excitation object, the calibration results are generated. Experimental results show that the proposed method can efficiently and repetitively detect a gravity gradient excitation mass weighing 260 kg within a range of 1.6 m and the scale factor of RAGG can be obtained as (5.4 ± 0.2) E/μV, which is consistent with the theoretical simulation. Error analyses reveal that the performance of the proposed calibration scheme is mainly limited by positioning error of the excitation and can be improved by applying higher accuracy position rails. Furthermore, the RAGG is expected to perform more efficiently and reliably in field tests in the future.

About Identification of Instrument Error Parameters for a Gravity Gradiometer

“…The first variant proposes the usage of a centrifuge (Yu abd Cai 2018). The second variant is based on the special motion of the disturbing mass (Deng et al 2018).…”

Error analysis of calibration for horizontal tensor rotating accelerometer gravity gradiometer

“…Gravity gradient calibration is a critically important step for evaluating the measurement level of a RAGG. 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.…”

Integration of Residual Terrain Modelling and the Equivalent Source Layer Method in Gravity Field Synthesis for Airborne Gravity Gradiometer Test Site Determination

“…Many other projects relying on alternative technologies have come into sight, e.g., the Superconducting Gradiometer developed by U.Maryland and by ARKEX company [13], MEMS gravity gradiometer by University of Twente [14], cold-atomic interferometer gravity gradiometer by Stanford University [15], quantum gravity gradiometer by Yale University, Università Degli Studi di Firenze, Observatoire de Paris and Office National d'Etudes et de Researches Aerospatiales (ONERA) [16][17][18][19][20][21]. Additionally, there are projects underway in China for the development of a rotating accelerometer gravity gradiometer and atom interferometry gravity gradiometer, which are expected to be used in aircraft for efficient gravity field detection over mountain and coastal areas [22][23][24][25]. Both of these gradiometers could achieve a 0.25 Hz sampling rate.…”