Example embodiments include an optical interrogation system with a sensing fiber having a single core, the single core having multiple light propagating modes. Interferometric apparatus probes the single core multimode sensing fiber over a range of predetermined wavelengths and detects measurement interferometric data associated with the multiple light propagating modes of the single core for each predetermined wavelength in the range. Data processing circuitry processes the measurement interferometric data associated with the multiple light propagating modes of the single core to determine one or more shape-sensing parameters of the sensing fiber from which the shape of the fiber in three dimensions can be determined.

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.

A monitoring system is disclosed herein that is configured to utilize a distributed sensing system to monitor both a cable and cable accessories included within a cable circuit. In various embodiments, the monitoring system may include a distributed sensing system and one or more cable accessory wrap assemblies. The distributed sensing system may include a distributed sensing fiber following (or integrated into) the cable and connected to a cable accessory wrap assembly for each of the one or more cable accessories in-line with cable. In various embodiments, each cable accessory wrap assembly may comprise a cable wrap embedded with a distributed sensing fiber. The distributing sensing fiber of a cable accessory wrap assembly may be configured to provide measurements to distributed sensing system indicating that an anomaly event occurred at a given cable accessory.

A monitoring system is disclosed herein that is configured to utilize a distributed sensing system to monitor both a cable and cable accessories included within a cable circuit. In various embodiments, the monitoring system may include a distributed sensing system and one or more cable accessory wrap assemblies. The distributed sensing system may include a distributed sensing fiber following (or integrated into) the cable and connected to a cable accessory wrap assembly for each of the one or more cable accessories in-line with cable. In various embodiments, each cable accessory wrap assembly may comprise a cable wrap embedded with a distributed sensing fiber. The distributing sensing fiber of a cable accessory wrap assembly may be configured to provide measurements to distributed sensing system indicating that an anomaly event occurred at a given cable accessory.

A sensing textile includes at least one assembly of optical fiber filaments, wherein the sensing textile has a main direction and a cross direction, and wherein the at least one assembly of optical fiber filaments is oriented at any angle measured relative to the cross direction.

At least one fiber-optic sensor unit measures a mechanical variable which affects a rail having a certain length and a neutral axis that extends along said length of the rail. The at least one fiber-optic sensor unit is disposed at an angle of 30 to 60, in particular 45, relative to the neutral axis or at an angle of 30 to 60, in particular 45, relative to the neutral axis. The at least one fiber-optic sensor unit is irradiated with primary light in order to generate a signaling light in a reflection mode or transmission mode. The intensity of the signaling light is sensed. The signaling light is evaluated.

An optical-based system for sensing parameters of a structure or machine for monitoring the health of the structure or machine. The optical-based system includes a set of optical fibers, each optical fiber including a set of fiber Bragg grating (FBG) sensors for sensing a set of parameters of the object; a set of interrogators configured to generate a set of incident optical signals for transmission via the set of optical fibers, respectively, receive a set of reflected optical signals from each of the optical fibers of the set, and generate a set of data related to sensed parameters of the object based on the set of reflected optical signals; and a controller configured to control the set of interrogators. Via a user interface or a remote computer on a cloud, sensing instructions may be provided to the controller, and sensed data and other information may be received from the controller.

An apparatus, and related method, relates generally to a fiber-optic sensing system. In such a system, fiber-optic sensors are in a rosette or rosette-like pattern. An optical circulator is coupled to receive a light signal from a broadband light source, to provide the light signal to the fiber-optic sensors, and to receive a returned optical signal from the fiber-optic sensors. A spectral engine is coupled to the optical circulator to receive the returned optical signal and configured to provide an output signal.

Devices, systems, and methods for flexible, deployable structures with optical fiber are provided in accordance with various embodiments. For example, some embodiments include a system that may include a flexible, deployable structure and one or more optical fibers coupled with the flexible, deployable structure. In some embodiments, one or more conditions of the one or more optical fibers coupled with a flexible, deployable structure may be determined. One or more conditions of the flexible, deployable structure may be determined utilizing the determined one or more conditions of the one or more optical fibers coupled with the flexible, deployable structure. The one or more conditions of the one or more optical fibers may be correlated to the one or more conditions of the flexible, deployable structure.

An apparatus for sensing a value of a property includes: an optical sensor having a single mode optical fiber responsive to the property; an optical interrogator having a tunable laser to transmit polarized light to the optical sensor, a photo-detector to receive sensor light, and a controller configured to process the received light and output the value of the property; and a passive random depolarizer disposed between the tunable laser and the single mode optical fiber and having (i) a first polarization maintaining (PM) optical fiber of length L1 having a first fast optical axis and a first slow optical axis and (ii) a second PM optical fiber of length L2 having a second fast optical axis and a second slow optical axis rotationally spliced to the first PM optical fiber in which the second fast and slow optical axes are offset from the first fast and slow optical axes.