Fiber Bragg grating-based load sensor without temperature dependence

Abstract

A novel load sensor has been proposed and demonstrated by embedding a fiber Bragg grating (FBG) into a tapered cylindrical polymer rod. Load-induced nonuniform strain field changes the bandwidth, and hence, the reflected optical power of the FBG. Temperature-insensitive measurement of load has been realized by measuring the reflected optical power with only a low-cost optical power meter. Load measurement sensitivity of 5.0 nW/N has been experimentally achieved within a range up to 1800 N.