Design of a Fiber Bragg Grating Pressure Sensor Based on a Metal Diaphragm and Lever Structure

Area of Science:

• Mechanical Engineering
• Sensor Technology
• Materials Science

Background:

• Traditional pressure sensors often face limitations in sensitivity and temperature stability.
• Developing robust sensing elements is crucial for accurate pressure monitoring across various applications.

Purpose of the Study:

• To design and analyze a novel pressure sensor utilizing a metal diaphragm and lever structure.
• To investigate the sensitization effectiveness and implement temperature compensation mechanisms.
• To optimize the sensor's performance for high-sensitivity, small-range pressure detection.

Main Methods:

• Finite element analysis (FEA) was employed to simulate the mechanical behavior of the sensor.
• Comparative analysis of different diaphragm materials and dimensions (e.g., square beryllium bronze) was performed.
• The influence of Fiber Bragg Grating (FBG) placement on the lever was studied to optimize sensitivity.
• A secondary FBG was integrated for real-time temperature compensation.

Main Results:

• A 1 mm thick, 20 mm side-length square beryllium bronze diaphragm exhibited optimal elastic properties.
• The combined diaphragm and lever structure significantly enhanced FBG sensitivity, achieving 3.35 nm/MPa.
• Temperature compensation was successfully demonstrated by incorporating a temperature-sensing FBG.
• Sensor sensitivity was tunable by adjusting FBG position.

Conclusions:

• The designed metal diaphragm and lever pressure sensor offers significantly improved sensitivity.
• The integrated temperature compensation ensures measurement accuracy under varying thermal conditions.
• This sensor is well-suited for applications requiring high sensitivity within a small pressure range.