Patent ID: 7856888
Filing Date: 2010-12-28
Classification: G01B,G01L,G01M

Abstract:
1. A gage carrier for a fiber optic strain gage comprising: a body having a passageway extending along its length for receiving an optical fiber containing one or more fiber Bragg gratings, the passageway having a longitudinal axis, a central portion of the body intersecting at least a portion of the passageway forming a mold cavity for receiving a fiber bonding material, and a fiber guide formed along the longitudinal axis of the passageway for receiving the optical fiber, the mold cavity positioned in the body, with respect to the passageway and the fiber guide, and the optical fiber inserted into the passageway and the fiber guide, such that the optical fiber is in the mold cavity, does not touch the sidewalls of the mold cavity and is positioned against the test specimen when the optical fiber is inserted in the passageway and the fiber guide and the gage carrier is positioned on the test specimen prior to injection of the fiber bonding material; a filling hole passing from the outside surface of the carrier into the mold cavity for introduction of fiber bonding material into the mold cavity and one or more vent holes passing from the outside surface of the carrier into the mold cavity and spaced apart from said filling hole to allow air to escape the mold cavity as fiber bonding material is introduced into the mold cavity; and a mounting surface for attaching the carrier to a test specimen, wherein the mold cavity has a depth and width such that on injection of fiber bonding material to completely fill the mold cavity after insertion of the optical fiber into the passageway and fiber guide and positioning of the gage on the test specimen, the inserted fiber bonding material bonds the optical fiber to the test specimen.