Three robust temperature-drift compensation strategies for a MEMS gravimeter

Abstract

Gravimeters fabricated with MEMS suffer from temperature-dependent drifts in their long-term stability. We analyze the thermal contributions to the signal, and we propose three mechanisms to mitigate their effects. The first one uses materials that fulfill the condition αE=−2α, where thermal expansion is canceled by the temperature variation of Young’s modulus. The second one uses the thermal expansion to introduce a compression that compensates variation in the force of the spring. In the third one, expansion compensates the displacement of the proof mass in the sensor, rather than the force. The three mechanisms are robust since they only depend on the temperature of the sensor itself.