Compact omnidirectional multicore fiber-based vector bending sensor

Area of Science:

• Optoelectronics
• Fiber Optics Sensors
• Material Science

Background:

• Fiber optic sensors are crucial for precise measurements.
• Existing sensors may lack accuracy in distinguishing bending direction and amplitude.
• Multicore fiber (MCF) offers unique spectral properties for sensing applications.

Purpose of the Study:

• To propose and demonstrate a compact and simple vector bending sensor.
• To achieve high accuracy in distinguishing both the direction and amplitude of bending.
• To develop a sensor with a wide measurement range (0° to 360°).

Main Methods:

• Utilizing a short segment of asymmetric multicore fiber (MCF) fusion spliced to a standard single mode fiber.
• Analyzing the shift and shrinkage of the reflection spectrum in response to bending.
• Simultaneously monitoring wavelength shift and light power variations.

Main Results:

• The sensor accurately distinguishes any bending direction and amplitude.
• The reflection spectrum exhibits specific shifts and shrinkage patterns correlating to bending.
• The sensor demonstrates high sensitivity, detecting bending angles below 1°.
• Full 360° orientation measurement capability was achieved.

Conclusions:

• The proposed MCF-based sensor offers a simple yet highly accurate method for vector bending measurement.
• Simultaneous monitoring of spectral shift and power variation enables unambiguous determination of bending parameters.
• This technology has potential applications in various fields requiring precise directional sensing.