2-DIMENSIONAL CONTOUR IMAGING WITH A FIBER OPTIC MICROBEND TACTILE SENSOR ARRAY

A four-layer two-dimensional fiber optic sensor array has been formed by using two layers of optical fibers as the corrugation structure to induce microbends in two orthogonal layers of active fibers sandwiched between the corrugation layers. This sensor array has been used to provide object position, orientation, size and contour information. An imaging algorithm which extracts two-dimensional force or tactile images from the sensor array is presented here. By using a technique of sensor translation and recognizing the dependency of light attenuation on the spatial distribution of microbends, exterior and interior contours of objects have been reconstructed. The imaging algorithm has been tested using sixteen different objects and all objects are reconstructed correctly. The efficiency of the algorithm and the weighted mean square error it introduces are also studied.