Wearable Sensing Glove With Embedded Hetero-Core Fiber-Optic Nerves for Unconstrained Hand Motion Capture

In this paper, we present a wearable sensing glove with embedded hetero-core fiber-optic nerve sensors that detect finger flexion to achieve unconstrained hand motion monitoring. The hetero-core fiber sensor is suited to the wearable sensing glove because it is capable of optical intensity-based measurements with excellent stability and repeatability using single-mode transmission fibers and is unaffected by temperature fluctuations. The hetero-core sensor elements are located on the back of the hand so that they are not affected by random wrinkles in the glove at the joints. As a result, the hetero-core flexion sensor after calibration is capable of detecting the joint angles of the fingers regardless of differences in hand size, and the hetero-core sensing technique enables the sensing glove to be constructed with a minimum number of sensor points. The optical loss performance of the hetero-core sensors reveals monotonic characteristics with respect to the flexion angle of joints. The optical loss is 1.35 dB for a flexion angle of approximately 97.2deg with accuracy of 0.89deg in the detected flexion angle. Real-time hand motion capture was demonstrated by means of the proposed sensing glove without restricting natural human behavior.