A number of fiber optic force sensors for MRI applications based on light intensity modulation have been proposed [20], [21], to name a few. Due to the limited space in the robot design, there is a need to miniaturize the sensor while retain the sensing range and resolution requirement. Fiber Bragg Grating (FBG) sensors seem to be a viable solution. FBG directly correlate the wavelength of light and the change in the desired strain. If the fiber is strained from applied loads then these gratings will change accordingly and allow a different wavelength to be reflected back from the fiber.
However, the costly optical source, FBG fibers and spectral analysis equipment present formidable application for medi-cal instrumentation. Fabry-Perot interference (FPI) fiber optic sensor provides an amiable solution for high-resolution force sensing that only relies on simple interference pattern based voltage measurement