Real-Time Digital Computer Acquisition and Computation of Gravity Data at Sea

Abstract

A system for the automatic acquisition and computation of gravity data at sea has been tested and is now operational aboard the Research Vessel CHAIN of the Wood's Hole Oceanographic Institution. This is the first recorded instance of on-line acquisition and processing of gravity data by the use of a digital computing system. Sampling and computation are performed in a one minute computation cycle making knowledge of gravity values, gravity anomalies and dead-reckoning position available in real-time. The system consists of a LaCoste-Romberg Sea Gravity Meter, data conversion units for computer compatibility with the gravity meter, ship's gyrocompass and ship's speed log, an IBM 1710 Mod 1 Control System (the combination of a 1620 Computer and a 1711 Data Converter for analog to digital conversion), and typewriter and paper tape input-output units.