Design and Fabrication of Ultra-Low Temperature Vibration Sensor Based on Self Excited Vibration Resonance Frequency Test

In the field of aerospace, deep space exploration is becoming more and more frequent, and the temperature deep in the universe is getting lower and lower. Specialized equipment for vibration monitoring of instruments under harsh conditions of ultra-low temperature is scarce, and how to design a vibration sensor to solve the vibration monitoring in ultra-low temperature environments is an urgent problem. In this paper, we propose a novel testing methodology known as Self-Excited Vibration Resonance Frequency Test of piezoelectric sheet in ultra-low temperature, which contributes to the ultra-low temperature survival verification of piezoelectric materials for ultra-low temperature vibration sensors. The method proves that the PZT-7A piezoelectric material can work in ultra-low temperature environments. The sensitivity of the ultra-low temperature vibration sensor was obtained by vibration test as well as temperature test to be 5.08 mV/g. It can work normally at -197°C-RT with small output signal noise. The ultra-low temperature vibration sensor designed in this paper has low cost and good low-temperature resistance. It can be widely used in structural health monitoring of instruments and equipment in ultra-low temperature environments.