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.

Embodiments disclosed herein include a substrate support having a sensor assembly, and processing chamber having the same. In one embodiment, a substrate support has a puck. The puck has a workpiece support surface and a gas hole exiting the workpiece support surface. A sensor assembly is disposed in the gas hole and configured to detect a metric indicative of a deflection of a workpiece disposed on the workpiece support surface, wherein the sensor assembly is configured to provide the benefit of allowing gas to flow past the sensor assembly when positioned in the gas hole.

A micro-machined optical pressure sensor, comprising: a diaphragm configured to deform when a force is applied thereto; and a sensing micro-ring spaced apart from the diaphragm by a gap, the gap being variable depending on the force applied on the diaphragm, wherein the sensing micro-ring is configured to produce a resonance wavelength shift when the gap is varied, the resonance wavelength shift indicative of the force applied to the diaphragm.

A method of monitoring corrosion of an electrical enclosure in a hazardous environment is provided. The method is implemented with at least one computing device in communication with at least one FBG optical sensor reflecting UV light in the electrical enclosure. The method includes measuring wavelength changes of UV light reflected by the at least one sensor, wherein the wavelength changes are a function of corrosion-related strain in the electrical enclosure. The method also includes computing, by the at least one computing device, the corrosion-related strain in the electrical enclosure based on the measured wavelength changes. The method further includes comparing, by the at least one computing device, the computed corrosion-related strain with a predetermined threshold, and recommending preventive corrosion-related maintenance based on the comparison.

A load sensing system for sensing a load on a structure can include an optical load sensing element configured to change an optical state based on a force applied thereto, an optical source operatively connected to the optical load sensing element and configured to input an input optical signal to the optical load element, and an optical detector configured to receive a returned optical signal from the optical load sensing element. The optical detector can be configured to detect one or more frequency peaks of the returned optical signal and to use the one or more frequency peaks of the returned optical signal to correlate to a load value of the load and output the load value indicative of the load.

A pressure sensing pad includes a flexible planar layer having a two-dimensional sensing area, and an optical fiber embedded in the plane of the flexible planar layer traversing the two-dimensional sensing area in a particular configuration. At least one end of the fiber optic strain sensor has a connector that is connectable to an interferometric-based fiber optic interrogation and processing system. When the connector is connected to the an interferometric-based fiber optic interrogation and processing system and pressure is applied to the pressure sensing pad, a signal from the optical fiber is provided to and processed by the interferometric-based fiber optic interrogation and processing system to determine a two-dimensional pressure map for the two-dimensional sensing area.

A system and method are presented for detecting and measuring pressure within a region of a body lumen or vessel. The pressure sensing system includes a light source for transmitting light through a pathway of polarization maintaining fiber optic wire. A distal portion of the polarization maintaining fiber optic wire is engaged to and extends along a guidewire. The distal portion of the fiber optic wire includes pressure sensing station(s) made up of fiber Bragg gratings (FBG). The light transmitted to and reflected from the FBGs on the two polarization modes of the polarization maintaining fiber optic wire can be analyzed to provide one or more pressure values.

In an example, this document discloses an apparatus for insertion into a body lumen, the apparatus comprising an optical fiber pressure sensor. The optical fiber pressure sensor comprises an optical fiber configured to transmit an optical sensing signal, a temperature compensated Fiber Bragg Grating (FBG) interferometer in optical communication with the optical fiber, the FBG interferometer configured to receive a pressure and modulate, in response to the received pressure, the optical sensing signal, and a sensor membrane in physical communication with the FBG interferometer, the membrane configured to transmit the received pressure to the FBG interferometer.

A fibre optic cable structure (300) suitable for fibre optic sensing with an improved sensitivity to an environmental parameter is described. The structure (300) includes an optical fibre (301) and a bend inducer (304) responsive to the environmental parameter to control bending of the optical fibre. The bend inducer (304) is configured to adopt a first configuration, that induces a first curvature of the optical fibre, at a first value of the environmental parameter and to adopt a second configuration at a second, different, value of the environmental parameter that induces a second, different, curvature of the optical fibre. By action of the bend inducer (304) a change in value of the environmental parameter imparts a bending force on the optical fibre.

Disclosed are a Fabry-Perot sensor and a method for manufacturing the same. A Fabry-Perot sensor including: a base part; a cavity formed between the base part and a pressure-sensitive film, and enclosed by the base part and the pressure-sensitive film; the pressure-sensitive film, fixed to the base part, wherein the pressure-sensitive film has one or more localised areas, each localised area has a doping substance doped into a base material of the pressure-sensitive film to produce stress, no localised area penetrates the entire thickness of the pressure-sensitive film, and under the effect of stress, the pressure-sensitive film has a corrugated structure; an optic fibre used for conducting a light signal, one end part of the optic fibre being fixed to an optic fibre mounting part of the base part, and the optic fibre mounting part being located at an end part of the base part opposite the cavity.