Superconducting techniques for gravity survey and inertial navigation

Conference · Fri Mar 01 04:00:00 EST 1985 · IEEE Trans. Magn.; (United States)

OSTI ID:6484641

Chan, H A; Moody, M V; Paik, H J; Parke, J W

Major improvements in sensitivity and drift can be made in inertial instruments by utilizing benign properties of materials available at liquid helium temperatures. We are developing a three-axis gravity gradiometer in which magnetic fields produced by persistent currents are modulated by motions of superconducting proof masses. Signals arising from both differential and common mode motions of the proof masses are detected by SQUIDs. The present design parameters give an intrinsic gravity gradient noise of 2 X 10/sup -12/ s/sup -2/ Hz /SUP -1/2/ , subject to improvements with new superconducting techniques under tests. A demonstration of such high sensitivity requires a very strict control of all error sources. The performance of our prototype gravity gradiometer when tested in a noisy terrestrial environment with its sensitive axis tilted at an angle of tan/sup -1/ 2 /SUP 1/2/ with respect to Earth's gravity is degraded to an error level of 7 X 10/sup -10/ s/sup -2/ Hz /SUP -1/2/ . In order to compensate for commonacceleration induced errors, we are also developing a six-axis superconducting accelerometer, based on a similar principle, which can detect the linear and angular acceleration vectors of the gradiometer platform simultaneously. Motion of a single, magnetically levitated, proof mass is monitored to resolve linear acceleration components to 4 X 10/sup -12/ m s/sup -2/ Hz /SUP -1/2/ and angular acceleration components to 3 X 10/sup -11/ rad s/sup -2/ Hz /SUP -1/2/ . This accelerometer, combined with the gradiometer, represents a gradiometer-aided inertial navigation/survey system.

• Research Organization: Univ. of Maryland, College Park, MD
• OSTI ID: 6484641
• Report Number(s): CONF-840937-
• Conference Information: Journal Name: IEEE Trans. Magn.; (United States) Journal Volume: MAG 21:2
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ACCELEROMETERS
ELECTRONIC EQUIPMENT
EQUIPMENT
ERRORS
FLUXMETERS
GEOPHYSICAL SURVEYS
GRAVIMETRY
GRAVITY SURVEYS
MEASURING INSTRUMENTS
MICROWAVE EQUIPMENT
NAVIGATIONAL INSTRUMENTS
PERFORMANCE TESTING
SENSITIVITY
SQUID DEVICES
SUPERCONDUCTING DEVICES
SUPERCONDUCTORS
SURVEYS
TESTING