High-temperature impact-resistant multi-parameter sensor with wide dynamic range based on an L-shaped cantilever beam...

Simultaneous monitoring for temperature, vibration, and strain is extremely urgent to characterize the operating status of engineering structures and equipment in many industrial fields. Here, we propose a high-temperature impact-resistant temperature-vibration-strain multi-parameter sensor with wide dynamic range based on an L-shaped cantilever beam structure. This sensor is composed of a sensitive fiber core body and an integrated impact-resistant sensitive structure, in order to ensure its operating stability and consistency. An Fabry-Pérot (F-P) cavity fabricated by arc discharge technology is installed on the L-shaped cantilever beam sensitive structure to achieve high-sensitivity vibration measurement. The double fiber Bragg gratings (FBGs) inscribed by femtosecond laser technique are fixed on an elastic sensitive structure and a packaging head to acquire strain and temperature signals in the range of 25-600 ℃, respectively. The self-developed sensor exhibits a high vibration sensitivity of 0.94 nm/g in the range of 0-70 g and has a wide frequency band of 10-2000 Hz. Besides, it has a large strain measurement range of 0-3112 με. Moreover, owing to its strong mechanical structure and high flexibility, it has potential application in extreme environments such as aerospace and oil exploration.