Development of Force Sensor System Based on Tri-Axial Fiber Bragg Grating with Flexure Structure

Area of Science:

• Biomedical Engineering
• Optical Sensing Technologies
• Medical Device Development

Background:

• Fiber Bragg grating (FBG) sensors are lightweight, flexible, and cost-effective optical sensors.
• FBG sensors exhibit high sensitivity to strain and temperature, making them suitable for precise force measurement.
• Current cardiac catheterization requires physicians to manually sense catheter tip force, necessitating improved sensing capabilities.

Purpose of the Study:

• To design and simulate an FBG-based force sensor system for cardiac catheterization.
• To verify the sensitivity and durability of FBG sensors integrated into flexure structures for catheter tip application.
• To develop a real-time force measurement system for catheter insertion.

Main Methods:

• FBG fibers were mounted on two distinct flexure structures and simulated using ANSYS.
• A system combining three FBGs and an interrogator was configured to capture wavelength signals.
• Calibration curves were generated by measuring wavelength changes with applied force (0.1–0.5 N range) at 0.01 N resolution.
• LabVIEW software was utilized to implement the calibration curve for real-time force measurement.

Main Results:

• Simulations verified the sensitivity and durability of the FBG sensor designs for catheter tip use.
• A high-resolution calibration curve was established, demonstrating the sensor's ability to detect small force variations.
• The FBG force sensor system successfully measured unknown forces in real time.

Conclusions:

• FBG force sensors are optimal for catheterization due to their small size, low cost, biocompatibility, and immunity to electromagnetic interference.
• The developed FBG sensor system provides a viable solution for precise, real-time force feedback during cardiac catheterization.
• This technology enhances safety and control during minimally invasive procedures.