Summary: | In the process of airborne gravity gradiometry for the full-tensor airborne gravity gradiometer (FTAGG), the attitude of the carrier and the fuel mass will seriously affect the accuracy of gravity gradiometry. A self-gradient is the gravity gradient produced by the surrounding masses, and the surrounding masses include distribution mass for the carrier mass and fuel mass. In this paper, in order to improve the accuracy of airborne gravity gradiometry, a self-gradient compensation model is proposed for FTAGG. The self-gradient compensation model is a fuction of attitude for carrier and time, and it includes parameters ralated to the distribution mass for the carrier. The influence of carrier attitude and fuel mass on the self-gradient are simulated and analyzed. Simulation shows that the self-gradient tensor element <inline-formula> <math display="inline"> <semantics> <mrow> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>x</mi> <mi>x</mi> </mrow> </msub> <mo>,</mo> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>x</mi> <mi>y</mi> </mrow> </msub> <mo>,</mo> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>x</mi> <mi>z</mi> </mrow> </msub> <mo>,</mo> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>y</mi> <mi>z</mi> </mrow> </msub> </mrow> </semantics> </math> </inline-formula> and <inline-formula> <math display="inline"> <semantics> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>z</mi> <mi>z</mi> </mrow> </msub> </semantics> </math> </inline-formula> are greatly affected by the middle part of the carrier, and the self-gradient tensor element <inline-formula> <math display="inline"> <semantics> <msub> <mi mathvariant="sans-serif">Γ</mi> <mrow> <mi>y</mi> <mi>z</mi> </mrow> </msub> </semantics> </math> </inline-formula> is affected by the carrier’s fuel mass in three attitudes. Further simulation experiments show that the presented self-gradient compensation method is valid, and the error of the self-gradient compensation is within 0.1 Eu. Furthermore, this method can provide an important reference for improving the accuracy of aviation gravity gradiometry.
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