Discussion. Studying the parameters of the Earth's gravitational field – the gravity
acceleration g (gravity) and its anomalies Δg required in geodesy, geophysics,
geodynamics and oceanography. Information about the Earth's gravitational field is
used in seismology (earthquake prediction), aviation and space equipment (correction
of the inertial navigation systems of missiles, planes, orbits of the spacecraft), for the
study of geodynamic phenomena, the implementation of the tasks of engineering
Geology, archaeology, cartography and the like [1]. On the aircraft measured Δg in
remote areas of the Earth at a speed greater than the speed of ground-based
measurements. For this purpose, use the aviation gravimetric system (AGS), the
sensitive element of which is gravimeter.
Today there are many types of gravimeters AGS, the principle of which is based
on different physical phenomena. At the Department of instrumentation in National
Technical University of Ukraine «Kyiv Polytechnic Institute named after Igor
Sikorsky» and at the Department automation and computer-integrated technologies in
Zhytomyr state technological University under the guidance of Professor Bezvesilna
O. been developing new types of gravimeters, which can be used as part of the AGS,
and in the stabilizer arms as sensing elements to measure acceleration [2-3].
Aviation
gravimetric
measurements in Europe were carried out with help of quartz
much damped GAL-C and string GSD gravimeters. In the USA they were carried out
by gravimeters of following type [3]: Bell (BGM-2, VM IX); Autonetics (VM-4G.VM-
7G); Arma (Lot D, D4E); PIGA (PIGA -16; PIGA-25). Testing showed possibility of
gravity acceleration measurements earring out with error not more than 10 mGI under
unfavorable, 6mGI-under favorable meteorological conditions.
Pointed out gravimeters, as a simplification, can be represented in the form of
devise of mass m placed at some distance 1 from sensitivity axis. When gravimetry
acceleration signal acts on device input the pendulum moment is arisen. Compensation
methods of pendulum moment arid main factors that have influence over stability of
gravimeters readings, which technical characteristics are represented at the table, are
enumerated at the table 1. It enables to compare them easily and to choose necessary
device type.
Quartz much damped gravimeters of GAL-C type showed them self to good
advantage during sea gravimetric surveys when averaging time can be large enough
and reading can be taken already when pendulum reaches static equilibrium location.
GAL-C is filter passing useful 1ow frequency signal of gravimetric acceleration and
suppressing high-frequency signal of interference.
String gravimeters of GSD type developed in VNII GEOFIZIKA are more
comfortable with reference to quick and precision digital reading of acceleration on the
airplane. Their advantages are tine constant infinitesimal that is important during
measurement of g on the airplane: unlimited in practice measurement range of input
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