Modeling of errors resulting from vehicle motions for CHZII mobile gravimeter and its performance verification during marine surveys

Mobile gravity survey plays a paramount role in many research fields, particularly geophysics and geodesy. Mobile gravimeters with delicate mechanisms and gyroscope-stabilized platforms are robust to motion-induced errors. In the past few years, a novel spring-based mobile gravimeter, CHZII, constructed with a sensitive probe based on an axisystematic mechanism and supported by a two-axis gyro platform, has been developed for mobile gravity surveys. This study mainly analyzes the system and models measurement errors derived from carrier motions. The system’s performance was varied in a laboratory and on the sea. The constructed system experimentally shows that the residual error introduced by carrier motions is less than 1 mGal (∼1 × 10−5 m/s2) in general working conditions due to the delicate mechanical design and precise assembly. A repeatability test for the CHZII engineering prototype and a comparison test with a KSS32 gravimeter have been conducted in 2016–2017, demonstrating that the measurement accuracy approaches 1.1 mGal, which is con-sistent with the expectation.