A Highly Stable and Sensitive MEMS-Based Gravimeter for Long-Term Earth Tides Observations

Precision measurements of local gravitational acceleration variations are great importance in geophysical surveys. With advantages such as cost-effectiveness and portability, Micro-Electro-Mechanical system (MEMS)-based gravimeters have shown the potential for long-term gravity measurements. In this paper, aiming to further improve stability instrument, design considerations evaluations a MEMS gravimeter presented. linear spring silicon proof-mass, low natural frequency ~14 Hz large range ~10300 mGal achieved with an ultra-low self-noise floor 1.2 μGal/√Hz@1 Hz. By implementing vacuum chamber system, pressure variation is reduced from hundreds Pa/day atmosphere ~6 Pa/day. addition, active temperature control can suppress fluctuations by 2 3 orders magnitude within band 1×10 -4 xmlns:xlink="http://www.w3.org/1999/xlink">-2 The proposed demonstrated via Earth tides observations 30-day time span, giving correlation coefficient 0.957 reference. An excellent bias instability ≤4 μGal 8-3000 s averaging range, representing one best performances date terms gravimeters. This shows high-performance petroleum mineral prospecting, seismology other applications.