A method and arrangement of fibre optic distributed sensing for detection of an event at an event location within a blind region including 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 analyzing the backscatter light to determine the event location so that a detection range of the fiber optic distribution range of the fiber-optic distributed sensing system is extended into a blind region conventionally not accessible for detecting acoustic disturbances or acoustic events.

A device for testing overall anchorage performance of a basalt fiber reinforced plastic (BFRP) anchor cable includes an anchor cable anchoring system and a data acquisition system. The anchor cable anchoring system includes a test bed, BFRP arranged over the test bed, and a distributed optical fiber bonded to a surface of the BFRP, the test bed being provided with an anchoring section at one end and an outer anchoring section at the other end, the anchoring section anchors one end of the BFRP, and the outer anchoring section anchors the other end of the BFRP. The data acquisition system includes a modem and a grating connected to two ends of the distributed optical fiber in series, and a center hole jack and a dynamometer arranged between the outer anchoring section and an end of the test bed, and the BFRP penetrates the center hole jack and the dynamometer.

A method, system, and computer program product for determining a core-to-ferrule offset of a ferrule for a fiber optic connector. A reference ferrule is physically aligned with a core imager by positioning the reference ferrule so that edges of the reference ferrule in a plurality of profile images are aligned with fiducial markers in the images. The reference ferrule is incrementally rotated about its longitudinal center access, a core image captured at each rotational angle, and a reference core-to-ferrule offset determined based on the core images. A test ferrule is physically aligned with the core imager by positioning the test ferrule so that edges of the test ferule are aligned with the edges of the reference ferrule in a plurality of profile images. The core-to-ferrule offset of the test ferrule is then determined based on an offset between the test and reference cores in a composite core image.

In an optical fiber monitoring system which detects physical disturbance or other parameters such as temperature or strain of a fiber where a monitor signal is transmitted along the optical fiber and analyzed to detect changes which are indicative of an event, a method is provided for periodically checking proper operation of the optical fiber monitoring system. A fiber disturbance actuator periodically causes a pattern of disturbances of a portion of the fiber at a predetermined location thereon where the disturbance is characteristic of the event to be monitored. The monitor signal is analyzed to detect the pattern of changes and in the event that expected changes are not detected, a warning is issued that the intrusion detection system is not properly operating.

A tank for pressurized gas, such as hydrogen, comprises a structure made of composite material and a sensor for detecting and locating a deformation of the structure. The sensor comprises at least two first linear sensitive elements, which are sensitive to a non-localized elongation, and are rigidly attached the structure and laid out substantially parallel to each other. A deformation of the structure is localized in a section defined by at least one of the first linear sensitive elements.

Provided are methods and apparatuses for testing imaging devices, which can include a testing apparatus a testing apparatus including a test chamber; a device receptacle inside the test chamber for holding a device under test; a target receptacle inside the test chamber for holding an optical target within a field of view of the device under test; a temperature controller configured to adjust a temperature proximate to the device receptacle; and an air curtain controller configured to generate an air curtain inside the test chamber between a location of the device receptacle and a location of the target receptacle, the air curtain thermally isolating the device receptacle from the target receptacle.

A measuring system and method that computes and analyzes sensor data fused with multiple mechanical and thermally induced strain measurements is provided. Further, the measuring system and method realizes physics-based relations between sensor readings due to mechanical and thermal sources by optimally de-coupling a total strain into its mechanical and thermal components. The measuring system and method also auto-tunes coefficients involved in the optimal de-coupling equations using sensor specification data and previous system test results for initialization.

An optical monitoring device for monitoring curvature along a flexible medical instrument including optical fibers, a light source to inject light into the optical fibers, a light receiver configured to measure an optical characteristic of reflected light from the optical fibers, a processor to analyze the measured optical characteristic to determine a curvature of the optical fibers, compare the curvature with a threshold curvature, determine a location along the optical fibers of the determined curvature, store previous curvatures and their associated location along the fibers in a storage, analyze the stored curvatures by counting or summing curvatures determined at a given location over time to predict breakdown of the flexible medical instrument, and produce an indication when the stored curvatures determined at the given location over time predict breakdown of the flexible medical instrument at the given location.

In an optical fiber monitoring system which detects physical disturbance or other parameters such as temperature or strain of a fiber where a monitor signal is transmitted along the optical fiber and analyzed to detect changes which are indicative of an event, a method is provided for periodically checking proper operation of the optical fiber monitoring system. A fiber disturbance actuator periodically causes a pattern of disturbances of a portion of the fiber at a predetermined location thereon where the disturbance is characteristic of the event to be monitored. The monitor signal is analyzed to detect the pattern of changes and in the event that expected changes are not detected, a warning is issued that the intrusion detection system is not properly operating.

In an optical fiber monitoring system which detects physical disturbance or other parameters such as temperature or strain of a fiber where a monitor signal is transmitted along the optical fiber and analyzed to detect changes which are indicative of an event, a method is provided for periodically checking proper operation of the optical fiber monitoring system. A fiber disturbance actuator periodically causes a pattern of disturbances of a portion of the fiber at a predetermined location thereon where the disturbance is characteristic of the event to be monitored. The monitor signal is analyzed to detect the pattern of changes and in the event that expected changes are not detected, a warning is issued that the intrusion detection system is not properly operating.