Abstract: A system and method are provided for determining wall thickness of a structure such as a metallic pressurized pipe. The system includes an optical fiber having a plurality of Fiber Bragg Gratings (FBGs), and a mounting for securing the FBGs over discrete portions of the exterior surface of the pipe such that strain in the pressurized pipe wall is transmitted to the FBGs. The system further includes a light source and a light sensor coupled to an end of the optical fiber. The light sensor converts light reflected back from the FBGs into electrical signals that a digital processor converts into strain measurements. The FBGs are mounted around portions of the pipe expected to have significant metal loss as well as portions of the pipe expected to have negligible metal loss.

Abstract: A system and method are provided for determining wall thickness of a structure such as a metallic pressurized pipe. The system includes an optical fiber having a plurality of Fiber Bragg Gratings (FBGs), and a mounting for securing the FBGs over discrete portions of the exterior surface of the pipe such that strain in the pressurized pipe wall is transmitted to the FBGs. The system further includes a light source and a light sensor coupled to an end of the optical fiber. The light sensor converts light reflected back from the FBGs into electrical signals that a digital processor converts into strain measurements. The FBGs are mounted around portions of the pipe expected to have significant metal loss as well as portions of the pipe expected to have negligible metal loss.

Abstract: Structural member bend radius sensor apparatus 90 comprises three fibre Bragg grating (FBG) strain sensors 102 provided within three optical fibres 14, 16, 18. The optical fibres 14, 16, 18 and the FBGs 102 are embedded within a part-cylindrical shaped carrier member 92. The fibres 14, 16, 18 are provided at three spaced locations across the shaped carrier member 92 so that, in use, the three respective FBG strain sensors will be located at three different angular positions around the circumference of the structural member (pipe) 68. Structural member shape measurement apparatus 100 comprises four bend radius sensor apparatus 90 provided at four bend radius measurement positions along the pipe 68. The four bend radius sensor apparatus 90 shown share their optical fibres 14, 16, 18, and a single shaped carrier member 92. The shape measurement apparatus 100 further comprises FBG interrogation apparatus 104.

Abstract: Structural member bend radius sensor apparatus 90 comprises three fibre Bragg grating (FBG) strain sensors 102 provided within three optical fibres 14, 16, 18. The optical fibres 14, 16, 18 and the FBGs 102 are embedded within a part-cylindrical shaped carrier member 92. The fibres 14, 16, 18 are provided at three spaced locations across the shaped carrier member 92 so that, in use, the three respective FBG strain sensors will be located at three different angular positions around the circumference of the structural member (pipe) 68. Structural member shape measurement apparatus 100 comprises four bend radius sensor apparatus 90 provided at four bend radius measurement positions along the pipe 68. The four bend radius sensor apparatus 90 shown share their optical fibres 14, 16, 18, and a single shaped carrier member 92. The shape measurement apparatus 100 further comprises FBG interrogation apparatus 104.