Simulating the signal of a torsion balance gravimeter
Authors: Antonova G.A.  
Published in issue: #11(16)/2017  
DOI: 10.18698/25418009201711189  
Category: Instrument Engineering, Metrology, InformationMeasuring Instruments and Systems  Chapter: Instruments and Measuring Methods 

Keywords: anomalous gravity field, tensor of secondorder 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 barbellshaped rod, deviating from the equilibrium state when the instrument moves in a nonhomogeneous gravity field specified by means of a tensor of secondorder 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 nonhomogeneous 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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