An optical fiber for measuring pressure comprising a core for guiding optical signals along a length of the core and a cladding layer including a plurality of stress applying parts disposed around the core. The plurality of stress applying parts are disposed parallel to and symmetrically around the core to induce intensified symmetric shear stress upon application of external pressure while preventing birefringence. The optical fiber provides improved strain sensitivity compared to a standard single-mode optical fiber.

An optical fiber sensing system according to the present disclosure includes: an optical fiber network (10) configured to detect first sensing information related to a first monitoring target and second sensing information related to a second monitoring target; a reception unit (21) configured to receive an optical signal from the optical fiber network (10); a specification unit (22) configured to specify a first monitoring target based on first sensing information superimposed on the optical signal and specify a second monitoring target based on second sensing information superimposed on the optical signal, and a provision unit (23) configured to provide information related to the first monitoring target and information related to the second monitoring target specified by the specification unit (22) for a service providing destination.

Various tactile sensors and associated methods are enabled. For instance, a sensing apparatus comprises a photosensitive sensor. A compound-eye structure is on the photosensitive sensor and an elastomer layer is on the compound-eye structure. A reflective layer is on the elastomer layer, opposite the compound-eye structure and a light source emits light between the reflective layer and the compound-eye structure.

An optical fiber measurement device includes a light source, a light detector, a direction-changing member, and a tension-applying member. The light source emits light toward an optical fiber. The light detector receives the light that has propagated through the optical fiber. The optical fiber is hung on the direction-changing member. The direction-changing member changes an extending direction of the optical fiber to extend downward, the optical fiber being optically connected to the light source and the light detector at each of two end parts of the optical fiber. The tension-applying member applies a tension to the optical fiber hanging from the direction-changing member.

A detection system according to the present disclosure includes an optical fiber (10) configured to detect environment information, an acquisition unit (21) configured to acquire the environment information included in an optical signal received from the optical fiber (10), and a detection unit (22) configured to detect an event in the vicinity of the optical fiber (10) on the basis of a first environment pattern based on environment information acquired from an optical signal associated to a first period and a second environment pattern based on environment information acquired from an optical signal associated to a second period.

According to examples, an optical fiber-based sensing membrane may include at least one optical fiber, and a substrate. The at least one optical fiber may be integrated in the substrate. The optical fiber-based sensing membrane may include, based on a specified geometric pattern of the at least one optical fiber, an optical fiber-based sensing membrane layout. The substrate may include a thickness and a material property that are specified to ascertain, via the at least one optical fiber and based on the optical fiber-based sensing membrane layout, a thermal and/or a mechanical property associated with a device, or a radiation level associated with a device environment.

An object of the present disclosure is to provide a method and an apparatus for acquiring curvature and torsion using an inexpensive sensor medium. Disclosed is a measurement apparatus including a fiber ribbon including a plurality of coated fibers arranged in parallel, a strain measurement unit that measures strain amounts of the plurality of coated fibers, and an arithmetic processing unit that calculates curvature and torsion of the fiber ribbon using a strain amount of a coated fiber arranged in a middle portion of the plurality of coated fibers and a strain amount of a coated fiber arranged in a marginal portion of the plurality of coated fibers.

Methods of measuring an anomaly, any induced change in physical parameters such as strain, temperature, and so forth, in an optical fiber. One method may include launching a plurality of probe pulses from a probe source; recording a Brillouin scattering spectrum from a plurality of reflection signals generated in the optical fiber, responsive to the plurality of probe pulses; determining a relative motion between the optical fiber and the anomaly during the recording the Brillouin back-scattering spectrum; and dynamically adjusting the Brillouin back-scattering spectrum according to the relative motion, or performing an adjustment of the Brillouin back-scattering spectrum after acquisition of the Brillouin back-scattering spectrum.

The invention discloses an underwater umbilical cable which is capable of temperature and vibration measuring and three-dimensional shape reconstruction, wherein underwater umbilical cable is used to connect underwater equipment and aquatic equipment; the underwater umbilical cable comprises an outer sheath, armored steel wires, an inner sheath, a power cable, a communication optical cable, a steel pipe, three strain measuring optical fibers, three temperature measuring optical fibers, a distributed optical fiber strain interrogator, a distributed optical fiber temperature interrogator and a processor. The invention can collect the operation status data of the umbilical cable for a long time. The collected data is highly objective, can truly reflect the real-time operation status of the umbilical cables, and plays an important role in guaranteeing the long-term submarine oil and gas exploitation.

A stretchable polymer fiber can be used to form stretchable polymer fiber-based strain sensors. The stretchable polymer fiber-based strain sensors have a much larger strain range than existing stretchable polymer fiber-based strain sensors, good biocompatibility, and similar Young’s modulus as the human body. Woven into fabrics, the strain sensors can map the strain distribution at different locations and in different directions. The stretchable polymer fiber-based strain sensors can be implemented as resistance-based strain sensors, optical waveguide-based strain sensors, and as a combination of optical waveguide-based and resistance-based strain sensors.