An optical fiber sensor system and method for monitoring a condition of a linear structure such as a pipeline is provided which is capable of providing continuous monitoring in the event of a break in the sensing optical fiber or fibers. The system includes at least one sensing fiber provided along the length of the linear structure, and first and second interrogation and laser pumping sub-systems disposed at opposite ends of the sensing fiber, each of which includes a reflectometer. The reflectometer of the first interrogation and laser pumping sub-system is connected to one end of the sensing fiber. The reflectometer of the second interrogation and laser pumping sub-system is coupled to either (i) an end of a second sensing fiber provided along the length of the linear structure which is opposite from the one end of the first sensing fiber, or (ii) the opposite end of the first sensing fiber. Before any break of the sensing fiber or fibers occurs, each reflectometer redundantly monitors the condition of the linear structure over its entire length. After any such break occurs, each reflectometer will continue to receive signals up to the point of the break from opposite ends of the structure.

A method of optical sensing comprises coupling an excitation optical signal into a first optical fiber to induce Rayleigh backscattering, thereby providing a backscattered signal. The backscattered signal is optically amplified in the first optical fiber, thereby providing an amplified backscattered signal. The amplified backscattered signal is coupled into a second optical fiber and is optically re-amplifying in the second optical fiber.

Brillouin fiber sensors can provide distributed measurements of parameters of interest over long distances in a fiber by measuring the Brillouin frequency shift as a function of position along the fiber. The Brillouin frequency shift may be determined, to within a small fraction of the Brillouin linewidth, by establishing a series of lasing modes that experience Brillouin amplification at discrete spatial locations in a test fiber. A linewidth narrowing and high intensity associated with the lasing transition enable precise measurements of the lasing frequency associated with each of the lasing modes. The Brillouin frequency may be determined based on the lasing frequency.

A drilling optimization collar for use proximate a drilling tool within a wellbore includes a fiber optic sensor filament that is sized and configured to fit within a groove formed within the drilling optimization collar. The drilling optimization collar may be a pipe segment that is sized and configured to be installed in a drill string proximate the drilling tool, and may have a plurality of sensor elements. All or a portion of the sensor elements may be formed by discrete segments of the sensor filament, and as such, the sensor filament includes sensor elements that are configured to sense a condition of the wellbore and a load on the drilling optimization collar.

It is proposed a method for monitoring an electrical power supply line comprised in a seismic cable and extending along the seismic cable. The seismic cable includes: a plurality of seismic sensors arranged along the seismic cable, a plurality of controllers arranged along the seismic cable, and an optical transmission line extending along the seismic cable for carrying data signals from or towards the controllers. The electrical power supply line supplies at least one pair of master and slave controllers. The master controller of a given pair of master and slave controllers performs a step of monitoring a portion of the electrical power supply line between the master and slave controllers, by using an optical loop established on a portion of the optical transmission line between the master and slave controllers, and starting from the master controller and passing through the slave controller.

A method for configuring a sensor of a non-interference stress management system is disclosed. The method may include determining a focal distance between a light transmitting fiber and a transmit lens, the focal distance configured to focus light from the transmit fiber to form a focused transmit beam, the transmit beam targeting a reflective structure. The method may further include positioning the light transmitting fiber and the transmit lens, wherein the light transmitting fiber and the transmit lens are separated by a transmit gap based on the focal distance and positioning a light receptive fiber and a receive lens to receive a focused reflected beam from the reflective structure, wherein the light receptive fiber is separated from the receive lens by a receive gap based on the focal distance.

Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously extend DFOS techniques to anomaly detection using optical magnetism switches (OMC) that are integrated into the DFOS system.

A method for monitoring at least one support structure in an above ground building, includes at least one strain gauge, wherein each of the strain gauges is attached to one of the support structures in the above ground building to detect the strain of the support structure at the area of attachment. An interrogator unit is connected to a gauge having a connection means providing access to the strain gauges for the interrogator unit, wherein the interrogator unit provides an output of strain values at each of the strain gauges. The embodiment also includes a monitoring system connected to the interrogator unit, wherein the monitoring system outputs an alarm signal when an evaluation of the strain value any of the strain gauges indicates a significant condition wherein the alarm signal in connected to the building control system to execute an action.

It is described a method and arrangement of fibre optic distributed sensing for detection of an event at an event location within a blind region, the method comprising: using at least one optical fibre arranged at least partly along an object to be monitored and at least one light pattern interrogator coupled with the optical fibre; injecting light patterns at subsequent times; detecting backscatter light from the light patterns; and analysing the backscatter light to determine the event location.

The present disclosure provides a secondary battery module capable of optically transmitting measurement data on characteristics of cells forming a battery pack and further reducing a complicated procedure of wiring. The secondary battery module of the present disclosure includes: a battery pack in which a plurality of cell units are connected, each of the cell units including a cell and a light-emitting unit, the cell including a stacked unit and an electrolyte, the light-emitting unit being configured to measure characteristics of the cell and generate an optical signal according to the characteristics; and an optical waveguide into which an optical signal is introduced from the light-emitting unit of each of the cell units, wherein the number of optical waveguides is less than the number of optical signals, and the optical waveguide provides a common optical path through which optical signals are propagated from the light-emitting units provided in the battery pack.