The Tokyo Surface Ship Gravity Meter: Recent Developments and Results of Comparison Measurements.

摘要

The Tokyo Surface Ship Gravity Meter (TSSG) employs a single vibrating string accelerometer which is inherently nonlinear. This leads to errors unless its frequency is essentially constant over the sampling intervals. A new processor incorporating pulse train logic and employing a rapid sampling rate of about 50/sec has been designed to replace the digital computer which used about 2/sec. A comparison of the TSSG equipped with the new processor and a gyro-stabilized LaCoste and Romberg (L and R) meter showed that the performance of the TSSG, 1972 version, is comparable with that of the L and R meter. Also, a comparison between results from the new processor and the old processor showed that the nonlinear rectification errors anticipated with the old processor were unexpectedly small as long as short period environmental accelerations were not great. These results suggest that most of the data obtained with the TSSG over the past 10 years are accurate to + or - 10 mgals. (Author)