A method of determination of deformation along a first direction of an equipment (1) in contact with hot material and including an inner face (3) in contact with the hot material and an outer face (4) opposite to the inner face (3) is provided. An equipment (1) in contact with hot material provided with means to determine its deformation along a first direction is also provided.

A fiber Bragg grating inclination sensor, including a semicircular substrate and a packaged fiber Bragg grating. The semicircular substrate is fixed on a first structural member. One endpoint of the semicircular substrate is bonded with one end of the packaged fiber Bragg grating, and the other end of the packaged fiber Bragg grating is connected to a second structural member. The first structural member is fixed to the second structural member perpendicular to the first structural member. The packaged fiber Bragg grating is arranged on a tangent to the semicircular substrate. The fiber Bragg grating sensor of the present invention has the advantages of anti-electromagnetic interference and high sensitiveness. The present invention has a simple structure, high measurement accuracy, good stability, thereby having broad application prospects.

A fiber Bragg grating inclination sensor, including a semicircular substrate and a packaged fiber Bragg grating. The semicircular substrate is fixed on a first structural member. One endpoint of the semicircular substrate is bonded with one end of the packaged fiber Bragg grating, and the other end of the packaged fiber Bragg grating is connected to a second structural member. The first structural member is fixed to the second structural member perpendicular to the first structural member. The packaged fiber Bragg grating is arranged on a tangent to the semicircular substrate. The fiber Bragg grating sensor of the present invention has the advantages of anti-electromagnetic interference and high sensitiveness. The present invention has a simple structure, high measurement accuracy, good stability, thereby having broad application prospects.

Apparatuses relate generally to a fiber optic cable. In such an apparatus, a housing has a channel or bore for receipt of a portion of the fiber optic cable having a fiber optic sensor. An acoustic interface layer is coupled to a surface of the housing to reduce stress wave coupling loss at an interface between the fiber optic sensor and a host structure surface. In another such apparatus, a patch structure is for a fiber optic cable coupled to a fiber optic voltage conditioner. In yet another such apparatus, a fiber optic voltage conditioner is coupled for optical communication to a fiber optic cable having a Fiber Bragg Grating sensor. The fiber optic voltage conditioner includes a tunable light source having a broadband light source or a gain medium configured to provide a narrowband light signal from a broadband light signal for providing to the fiber optic cable.

A method of monitoring mechanical behavior of an undersea pipe (2) transporting fluid under pressure and made by assembling a plurality of unit pipe elements (4). A calibration step is performed consisting of using a measurement cable having an optical fiber sensor to measure deformations experienced by each pipe element while it is subjected on land to various mechanical stresses in predetermined directions and magnitudes, and, on the basis of the measurements, establishing the mechanical signature of each pipe element. A monitoring step is performed consisting of using a measurement cable (18) having an optical fiber sensor that makes uses Brillouin backscattering and is helically positioned at constant pitch (p) on each pipe element with the handedness of the helical pitch alternating for two adjacent pipe elements to recover variations in optical signal injected into the sensors while the pipe is in service.

A method for non-intrusive pipeline testing involves constructing the pipeline at a construction location that is above ground, affixing an optical fiber along a surface of a length of the pipeline that is at the construction location, measuring dynamic strain experienced by the length of the pipeline by performing optical interferometry using the optical fiber, and moving the length of the pipeline from the construction location to a different installation location. The optical fiber includes at least one pair of fiber Bragg gratings (FBGs) tuned to reflect substantially identical wavelengths with a segment of the optical fiber extending between the FBGs.

A transformer system includes a transformer and a transformer tank. The transformer tank houses the transformer in a bath of a dielectric fluid. The transformer system also includes a controller, and a fiber optic pressure sensor communicatively coupled to the controller. The fiber optic sensor is disposed in the dielectric fluid and operative to provide an output that varies with the pressure of the dielectric fluid. The controller is operative to determine the pressure of the dielectric fluid based on the output of the fiber optic pressure sensor.

An aircraft health diagnostic device is provided with a control unit that carries out structural health monitoring of a structure of an aircraft. The control unit has a first risk assessment unit that assesses the risk of damage occurring in the structure on the basis of a correlation between reference data stored in a storage unit and a signal data set based on measurement data obtained through measurement carried out by a measuring instrument, a second risk assessment unit that assesses the risk of damage occurring in the structure on the basis of the time-sequence change in the behavior of the signal data set, and a maintenance assessment unit that assesses the life, repair timing, and a maintenance plan of the structure on the basis of the time-sequence change in the behavior of the signal data set.

A method of detecting a damage of a wind turbine blade of a wind turbine rotor includes: a light input step of inputting light into a fiber-optic sensor mounted to the wind turbine blade; a light detection step of detecting reflection light from the grating portion; an obtaining step of obtaining a wavelength fluctuation index representing a fluctuation amount of a wavelength of the reflection light detected in the light detection step; and a detection step. The detection step includes detecting the presence or the absence of the damage of the wind turbine blade based on the wavelength fluctuation index taking account of a correlation between the wavelength fluctuation index of the wind turbine blade and a load index related to a load applied to the wind turbine blade, or a correlation between the wavelength fluctuation index and a temperature index related to a temperature of the wind turbine blade.

An optical fiber sensor device includes a control section configured to compute a physical quantity in an optical fiber installed at plural measurement locations based on intensity of scattered light received, and to compute an average of the computed physical quantity for the optical fiber. The control section is configured to compute the average of the physical quantity based on the computed physical quantity and on a length of the optical fiber. A length of the optical fiber installed at the measurement location is increased as a distance between a light source and the respective measurement location increases.