Finger motion detection based on optical fiber Bragg grating with polyimide substrate

Gestures play an important role in human-computer interaction, which provides a natural way for human-machine communication. In this paper, we proposed a new finger motion detection method based on optical fiber Bragg grating (FBG) with polyimide substrate. Several FBGs with polyimide substrate were fixed on the forearm to monitor the deformation around the forearm caused by finger motion. Firstly, the sensors layout was determined according to the distribution of forearm muscles which control finger motions, and the arrangement of FBGs was optimized. Then, through a series of tests, the response characteristics and applicability of the proposed FBG with polyimide substrate were verified. The tests results show that FBG with polyimide substrate has a high sensitivity, good linearity, low hysteresis error and good creep resistance compared with other two substrates. In the experiment of finger motion detection, test data based on six static gestures was adopted to evaluate the availability of the FBGs. The experimental results show that the proposed method can detect six static gestures effectively, and the FBG output signal has good repeatability under the same gesture. This is the first attempt to use FBGs to detect fingers’ monitor by monitoring deformations at the forearm, which is a technique with wide application prospects. © 2022 Elsevier B.V.