Bezvesilna O.
Doctor of Technical Sciences, Professor, Professor of Instrumentation
Department, National Technical University of Ukraine «Igor Sikorsky Kyiv
Polytechnic Institute», Kyiv, Ukraine
Tkachuk A.
PhD, Head of the automation and computer-integrated technologies to them. prof.
B.B. Samotokin Department, Zhytomyr State Technological University, Zhуtomуr,
Ukraine
SCIENTIFIC AND THEORETICAL DEVELOPMENT OF STABILIZATION
SYSTEMS FOR GRAVIMETRIC SYSTEMS AND MODERN SENSING
ELEMENTS FOR MEASURING GRAVITATIONAL ACCELERATION
Introduction. The indication of gravity anomalies from aircraft requires a
combination of several instrumentation components, each of which is designed for the
role of measurement or signal processing. The aggregate assemblage of these
components constitutes an airborne gravimetric system. Subsets of this assemblage of
components which relate system outputs to inputs will be termed the subsystems of the
airborne
gravimetric
system. The present task is therefore to determine the number,
function, and accuracy of the subsystems which make up an airborne
gravimetric
system.
A system for airborne gravimetry consists of five functional subsystems for 1)
specific force measurement, 2) geometric stabilization, 3) terrestrial navigation, 4)
altimetry, and 5) computation. In determining the accuracy required of such a system
we must recall that the only use for global gravity data is the computation of geoid
heights and deflections of the vertical. Overall system accuracy should then be
evaluated in terms of the resulting accuracy in these computations. Measurement
accuracies on the order of ±1 to 3 mGl may ultimately be required.
In order to carry out a gravity survey from a moving vehicle, some means of
stabilizing the gravimeter along a reference direction is required. Since it is ultimately
necessary to deduce the specific force in the direction of the local geographic vertical,
the direct instrumentation of the vertical provides the most desirable measurement
environment. Instrumentation of the vertical on a moving base requires however, a
rather complex subsystem using grade inertial components, and involves real time
computation using precise navigation data. The drawbacks of complexity are reduced
somewhat by the fact that such a stabilization system can also serve as the heart of a
geographic inertial navigator.
As an alternate to stabilization along the vertical, the gravimetr may be allowed
to track the apparent vertical, provided the proper compensation term is added to' the
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