Simulating the signal of a torsion balance gravimeter

Authors: Antonova G.A.
Published in issue: #11(16)/2017
DOI: 10.18698/2541-8009-2017-11-189
Category: Instrument Engineering, Metrology, Information-Measuring Instruments and Systems | Chapter: Instruments and Measuring Methods
Keywords: anomalous gravity field, tensor of second-order derivatives, Eötvös tensor, gravity gradiometer, gravimeter, gravitational potential
Published: 30.10.2017

Studying the structure of a torsion balance gravimeter helped us to construct a model of its oscillator system that makes it possible to predict the behaviour of an informative parameter, the deflection angle of its barbell-shaped rod, deviating from the equilibrium state when the instrument moves in a non-homogeneous gravity field specified by means of a tensor of second-order gravitational potential derivatives (the Eötvös tensor). We derived expressions for computing the Eötvös tensor for a gravity field generated by a preset distribution of point masses. We implemented a simulation that makes it possible to compute the signal emitted by a torsion balance gravimeter moving in a non-homogeneous gravity field, taking into account a number of structural parameters and errors, such as the quality factor of the oscillator system, a discrepancy in the resonant frequencies of the barbells, etc.

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