Diaphragms simulation, fabrication, and testing of a high temperature fiber optic F-P accelerometer based on MEMS

High-sensitivity detection of vibrations under high temperatures is a topic of great interest in modern engineering such as thermal engine deep-sea aquaculture factory ship, aerospace, high temperature casting, energy, etc. As traditional accelerometers and some fiber optic F-P accelerometers have shown their sensing limits at about 400 & DEG;C and 650 & DEG;C, respectively, a high temperature fiber optic F-P accelerometer based on MEMS technology is proposed. To obtain a high-performance chip for the sensor, an examination of the theoretical performance of an L and T-shaped cantilever beam diaphragm shows a sensitivity of 15.05 nm/g and 53.7 nm/g, respectively, and a wide working frequency range. Thanks to the designed sensor's various protections, frequency measurements with a high-temperature performance of 850 & DEG;C are recorded. The L-shaped cantilever beams diaphragm allows the sensor measurements at 850 & DEG;C with a repeatability of 5.46%, a working frequency range of 100-1000 Hz, an experimental sensitivity of 389 mV/g, an overall stability of 8 jumps at its adjacent frequency resolution range over 150 measurements, a linearity of 0.9856 and a maximum relative error maintained below 1.72%. In the field of application, it also exhibits a good relative error of measurement respecting the technical specification of 5 Hz.& COPY; 2023 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

High-sensitivity vibration detection under high temperatures is of great interest in modern engineering. This paper proposes a high temperature fiber optic F-P accelerometer based on MEMS technology, which exhibits reliable and high-temperature performance at 850°C.