Optical fiber tactile sensor based on fiber specklegram analysis

An optical fiber tactile sensor based on specklegram analysis is demonstrated. The system consists of microbending transducers attached to semi-rigid plates and distributed in form of array. The specklegrams produced by the multimode fibers are recorded and them the variations on fiber status, related to force magnitude, are assessed by specklegrams correlation. Finally, the spatial information was obtained by using a data fusion approach based on Bayesian inference. The sensor presented ~0.08 N sensitivity and ~1 mm resolution. Moreover, the data fusion technique provided the estimation of force distribution over a 30 × 30 mm
²
area using only 3 fibers.