Release time:2021-07-08 Hits:
- Indexed by:Journal paper
- First Author:WU WENJIE
- Correspondence Author:tuliangcheng
- Co-author:LIU JIN QUAN,FAN JI,pengdanhua,LIU HUAFENG
- Journal:Sensors and Actuators A: Physical
- Included Journals:SCI、SSCI
- Discipline:Engineering
- First-Level Discipline:Electronic Science And Technology
- Document Type:J
- Volume:280
- Key Words:MEMS Three-axisSeismic sensor Levelling-free Capacitance arraya
- DOI number:10.1016/j.sna.2018.07.050
- Date of Publication:2018-07-24
- Impact Factor:2.31
- Abstract:tHigh-precision seismic sensors are key components in geophysical applications. Traditional seismic sen-sors apply levelling systems to avoid overload by the gravity projection, introducing additional volume,weight and cost. In this paper, we design, fabricate and experimentally demonstrate a levelling-freesingle-axis in-plane seismic sensor based on MEMS technology. Three kinds of capacitive sensors areintegrated into one chip. Two encoder-like area-varying capacitive displacement sensors work alterna-tively to avoid the inflection points, enabling the seismic sensor to work linearly in arbitrary attitudeswith a high sensitivity and an angle sensor selects the working array from the two arrays and measuresthe angle between the sensitive direction and gravity direction at the same time. In order to calibrate thescale factor, a gap-varying capacitive displacement sensor is integrated to measure the spacing. By thecombination of these capacitive sensors, the micromachined seismic sensor is able to work in arbitraryattitudes with a resolution of better than 50 ng/√Hz at 1 atmosphere. Assembling three seismic sensorsalong axes orthogonal to each other, a three-axis seismic measurement system can be constructed. Thissystem has successfully detected a MS7.0 earthquake at 2017-08-08 (UTC time), which happened inSichuan Province (1000 km away), and another MS6.6 earthquake happened about 10 h later in XinjiangProvince (2700 km away). Being low cost and low power, this nano-g MEMS seismic sensor provides analternative solution for geophysical applications.
