An MRI-compatible force sensor for measuring differential isometric precision grip force.

Area of Science:

• Biomedical Engineering
• Neuroscience
• Rehabilitation Engineering

Background:

• Investigating neural correlates of fine motor control in magnetic resonance imaging (MRI) environments presents significant sensor design challenges.
• Accurate measurement of finger forces is essential for understanding precision grip and motor control.

Purpose of the Study:

• To design, characterize, and evaluate an MR-compatible precision grip sensor.
• To independently measure forefinger and thumb forces during precision grip tasks.

Main Methods:

• Selective laser sintering of Nylon 12 to create a sensor flexure.
• Integration of optical fibers for deformation measurement.
• Finite element model (FEM) simulation for design validation.
• Performance evaluation within a low force range (< 20 N).

Main Results:

• The MR-compatible sensor successfully measured forces in the desired low range.
• Optical fiber deformation measurements correlated well with FEM simulations.
• Some hysteresis was observed at higher frequencies, as anticipated.

Conclusions:

• The developed sensor meets performance specifications for measuring finger forces in an MR environment.
• This device enables advanced research into neural correlates of motor control under magnetic conditions.