A MEMS-Based Electrochemical Angular Accelerometer With a Force-Balanced Negative Feedback

Abstract

This paper presents a MEMS based electrochemical angular accelerometer with feedback where the relative movement between the liquid inertial mass and the sensitive microelectrodes was counter balanced by the feedback force. Theoretical analysis was conducted to model the response of the angular accelerometer with feedback. Both sensitive and feedback electrodes were made based on microfabrication and assembled to form MEMS based electrochemical angular accelerometer with feedback. Device characterization was conducted, locating a sensitivity of 8 V/(rad/s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> ), a bandwidth of 0.0083-8 Hz and a noise level of 6.31×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-7</sup> (rad/ s <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> )/√ Hz. In comparison to previously reported MEMS based electrochemical angular accelerometer without feedback, a significant improvement at low frequencies in 3dB bandwidth (0.0083-8 Hz vs. 0.02-10 Hz) was achieved due to the inclusion of the feedback part. This study can provide a new perspective for the development of electrochemical angular accelerometer, which may be further used in seismic monitoring.