An assembly is provided for an aircraft. This aircraft assembly includes a fuselage and a second system. The fuselage includes a wall and a hatch configured to close an opening in the wall. The sensor system includes an optical fiber, a transmitter and a receiver. The optical fiber is arranged at an interface between the hatch and the wall. The transmitter is configured to transmit first electromagnetic radiation into the optical fiber. The receiver is configured to detect second electromagnetic radiation received from the optical fiber to provide receiver data. The sensor system is configured to detect fluid leakage across the interface between the hatch and the wall based on the receiver data.

Aspects of the present disclosure describe monitoring of optical fiber by distributed temperature sensing (DTS) and determining optical fiber degradation and/or abnormal environmental events including landslides, fires, etc., from DTS data.

Aspects of the present disclosure describe monitoring of optical fiber by distributed temperature sensing (DTS) and determining optical fiber degradation and/or abnormal environmental events including landslides, fires, etc., from DTS data.

A method for selecting between a first battery cell and a second battery cells includes sensing a total generated heat flow rate emitted by the first battery cell and the second battery cells. The method further includes recording, for the first and second battery cells, first and second sets of heat flow rate data related to the total generated heat flow rate emitted by the first and second battery cells, respectively, over their first charge. The method further includes comparing the first set of heat flow rate data with the second set of heat flow rate data, and selecting one of the first or second battery cells according to the comparison between the first set of heat flow rate data with the second set of heat flow rate data.

A method for selecting between a first battery cell and a second battery cells includes sensing a total generated heat flow rate emitted by the first battery cell and the second battery cells. The method further includes recording, for the first and second battery cells, first and second sets of heat flow rate data related to the total generated heat flow rate emitted by the first and second battery cells, respectively, over their first charge. The method further includes comparing the first set of heat flow rate data with the second set of heat flow rate data, and selecting one of the first or second battery cells according to the comparison between the first set of heat flow rate data with the second set of heat flow rate data.

A fuel gauging sensing device for a fuel tank for aircrafts includes an optical fiber harness along the internal surface of the tank, a master optical controller connected to a first terminal of the optical fiber harness, a slave optical controller connected to a second terminal of the optical fiber harness, wherein the optical fiber harness includes Fiber Bragg Grating (FBG) sensors spaced in the optical fiber harness between 1 mm and 25 mm to provide temperature gradients inside the tank and wherein the master and slave optical controllers are configured to obtain the fuel gauging of the tank based on the output from the FBG sensors.

An optical fiber includes multiple optical waveguides configured in the fiber. An interferometric measurement system mitigates or compensates for the errors imposed by differences in a shape sensing optical fiber's response to temperature and strain. A 3-D shape and/or position are calculated from a set of distributed strain measurements acquired for a multi-core optical shape sensing fiber that compensates for these non-linear errors using one or more additional cores in the multicore fiber that react differently to temperature changes than the existing cores.

A method includes collecting spectral data from fiber Bragg grating sensors distributed at locations along a fiber optic component positioned along a streamer; and analyzing the spectral data to produce measurements of bend of an axis of the streamer proximate the locations. A streamer monitoring system includes: a fiber optic component positioned along a streamer; a plurality of fiber Bragg grating sensors distributed at locations along the fiber optic component; a light source optically coupled to the fiber optic component and configured to interrogate the fiber Bragg grating sensors; a photodetector optically coupled to the fiber optic component and configured to collect spectral data from the interrogated fiber Bragg grating sensors; and a spectral analyzer in communication with the photodetector and configured to analyze the spectral data to produce measurements of bend of an axis of the streamer proximate the locations along the fiber optic component.

The present disclosure relates to an arrangement (100) for obtaining a quantity related to a temperature along a part of an optical fibre (110). The arrangement comprises a light emitter (120) arranged to emit light into the optical fibre (110). The optical fibre is at at least one location along said part of the optical fibre provided with a Fibre Bragg Gratings, FBGs (111, 112, 113), wherein the FBGs are arranged to reflect light within a predetermined wavelength range. The arrangement further comprises a detector (160) arranged to receive and detect the reflected light, a first optical shutter (130) arranged in the optical path after the light emitter. The first optical shutter is arranged to be opened and closed in order to let the emitted light through and into the optical fibre (110), a second optical shutter (150) arranged to be opened and closed in order to let the reflected light through, and an optical circulator (140) having a first, a second and a third port. The optical circulator is operatively connected to the first optical shutter (130) at the first port, to the part of the optical fibre provided with the FBGs (111, 112) at the second port, and to the second optical shutter (150) at the third port. A control unit (180) is arranged to control the first optical shutter (130) and the second optical shutter (150). The control unit (180) is arranged to coordinate the timing of the opening of the first optical shutter (130) and the second optical shutter (150), respectively.

The present disclosure relates to an arrangement (100) for obtaining a quantity related to a temperature along a part of an optical fibre (110). The arrangement comprises a light emitter (120) arranged to emit light into the optical fibre (110). The optical fibre is at at least one location along said part of the optical fibre provided with a Fibre Bragg Gratings, FBGs (111, 112, 113), wherein the FBGs are arranged to reflect light within a predetermined wavelength range. The arrangement further comprises a detector (160) arranged to receive and detect the reflected light, a first optical shutter (130) arranged in the optical path after the light emitter. The first optical shutter is arranged to be opened and closed in order to let the emitted light through and into the optical fibre (110), a second optical shutter (150) arranged to be opened and closed in order to let the reflected light through, and an optical circulator (140) having a first, a second and a third port. The optical circulator is operatively connected to the first optical shutter (130) at the first port, to the part of the optical fibre provided with the FBGs (111, 112) at the second port, and to the second optical shutter (150) at the third port. A control unit (180) is arranged to control the first optical shutter (130) and the second optical shutter (150). The control unit (180) is arranged to coordinate the timing of the opening of the first optical shutter (130) and the second optical shutter (150), respectively.