A high-resolution micro-electro-mechanical resonant tilt sensor

作者：Zou Xudong; Thiruvenkatanathan Pradyurnna; Seshia Ashwin A^*

来源：Sensors and Actuators A: Physical , 2014, 220: 168-177.

DOI：10.1016/j.sna.2014.10.004

• MEMS
• Tilt sensors
• Resonant sensors
• Double-ended tuning fork resonators
• Oscillators

This paper reports on the design and experimental evaluation of a high-resolution micro-electromechanical (MEM) tilt sensor based on resonant sensing principles. The sensors incorporate a pair of double-ended tuning fork (DETF) resonant strain gauges, the mechanical resonant frequencies of which shift in proportion to an axial force induced by variations in the component of gravitational acceleration along a specified input axis. An analysis of the structural design of such sensors (using analytical and finite element modelling) is presented, followed by experimental test results from device prototypes fabricated using a silicon-on-insulator (SOI) MEMS technology. This paper reports measurement conducted to quantify sensor scale factor, temperature sensitivity, scale factor linearity and resolution. It is demonstrated that such sensors provide a +/- 90 degrees dynamic range for tilt measurements with a temperature sensitivity of nearly 500 ppb/K (equating to systematic sensitivity error of approximately 0.007 degrees/K). When configured as a tilt sensor, it is also shown that the scale factor linearity is better than 1.4% for a +/- 20 degrees tilt angle range. The bias stability of a micro-fabricated prototype is below 500 ng for an averaging time of 0.8 s making these devices a potentially attractive option for numerous precision tilt sensing applications.

• 出版日期2014-12-1