A MEMS Gravimeter Qualified for Earth Tides Measurement

This paper presents a MEMS gravimeter that is sensitive and stable enough to observe earth tides. A novel quasi-zero stiffness suspension, which includes a curved beam and two folded beams, is used to achieve an ultra-low resonant frequency of 3.0 Hz. The measured acceleration noise floor of the MEMS gravimeter is 20 μGal/√Hz at 1 Hz. The MEMS gravimeter shows a good agreement with the theoretical model for earth tides measurements. The results indicate that the proposed MEMS gravimeter is qualified for earth tides measurement and is promising to be a very low-cost gravimeter.