A Motion Monitor Using Hetero-Core Optical Fiber Sensors Sewed in Sportswear to Trace Trunk Motion

In this paper, a cameraless motion monitor has been described by introducing very thin sensor modules into sportswear, in which a single-mode hetero-core optical fiber sensor is fabricated. An elbow joint motion and a trunk motion are monitored by a sportswear on which the hetero-core optical fiber sensor modules are sewed so as to be sensitive to stretch on the wear. In order to get rid of the restriction to the human body, a two-plane model has been proposed in which only two sets of sensors simplify three kinds of motions at the trunk, which are anteflexion, lateral bending, and rotation. Additionally, the real-time monitoring system has been tested when golf swing motion is performed. As a result, it has been indicated that the motion, which consists of a composite of three motions, can be significantly analyzed by means of the two sensors. The developed system is viable to an unconstrained motion capture system intended for a teaching device in sports and rehabilitation fields.