Abstract: The invention relates to a method 100 for determining a pressure in a vacuum system, wherein the method comprises the steps of: a) generating 101 a plasma in a sample chamber which is fluid-dynamically connected to the vacuum system and which is in electrical contact with a first electrode and a second electrode; b) measuring 102 a current intensity of an electrical current flowing through the plasma between the first electrode and the second electrode; c) measuring 103 a first radiation intensity of electromagnetic radiation of a first wavelength range which is emitted from the plasma, wherein the first wavelength range contains at least a first emission line of a first plasma species of a first chemical element; d) measuring 104 a second radiation intensity of electromagnetic radiation of a second wavelength range which is emitted from the plasma, wherein the second wavelength range contains a second emission line of the first plasma species of the first chemical element or of a second plasma species of

Abstract: A pressure sensor includes: a light source that outputs signal light; a sensor optical fiber where the signal light is input and the signal light is propagated with a loss of 0.3 dB/m or more; and an optical receiver that receives the signal light propagated through the sensor optical fiber. Further, pressure applied to the sensor optical fiber is detected on a basis of intensity of the signal light received by the optical receiver.

Abstract: A blood pressure analysis system/method allowing conversion from an analog sensor input to a standardized analog output interface is disclosed. In some preferred embodiments the system/method permits a fiber optic pressure sensor to be interfaced to a standard patient care monitor (PCM) system using standardized Wheatstone Bridge analog interface inputs. Within this context the Wheatstone Bridge sensed output is defined by stimulus from the PCM and modulation of bridge element values by the conditioned output of an analog pressure sensor. The use of analog-to-digital-to-analog conversion in this blood pressure analysis permits retrofitting of PCM devices having analog Wheatstone Bridge inputs with advanced patient monitoring sensors without the need for specialized modifications to the baseline PCM data collection framework.

Abstract: The present invention relates to cover for a pressure sensor. The cover is configured for being arranged to cover a sensor element.

Abstract: A torsion balance is provided which includes a twisting wire and a reflector. The twisting wire is a suspended carbon nanotube. The reflector is hung on the twisting wire. The reflector further includes a film, a first reflecting layer, and a second reflecting layer; and the film includes a first surface and a second surface opposite to the first surface, and the first reflecting layer is located on the first surface and the second reflecting layer is located on the second surface.

Abstract: A method of wrapping optical fiber around a fluid conduit. The optical fiber is wrapped at least partially around the conduit. The optical fiber is secured relative to the conduit at one or more securing locations, thereby defining a sequence of multiple optical fiber portions. Each optical fiber portion comprises a portion of the optical fiber. Each securing location delimits a given optical fiber portion from the subsequent optical fiber portion in the sequence of optical fiber portions. A direction of wrapping of each consecutive optical fiber portion in the sequence of optical fiber portions may be alternated between a clockwise direction and a counter-clockwise direction.

Abstract: A pressure measurement system includes a pressure pod with two chambers separated by a diaphragm such that a deformation/movement of the diaphragm is indicative of a difference between the pressures of the two chambers. Such deformation/movement is detected by a device that has no physical contact with the diaphragm, for example, by an optical detector that detects a change in the shape of the diaphragm or a movement of a protrusion on the diaphragm.

Abstract: Provided is a hollow organ model unit. The hollow organ model unit includes a base that includes a recessed part, a hollow organ model that is placed in the recessed part, a filler that is filled in the recessed part, and a sensor that performs a measurement on the hollow organ model.

Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: A tire failure prediction system includes first and second temperature sensors to detect temperatures of first and second tires mounted on a traveling vehicle, a temperature acquisition unit to acquire the temperatures detected by the first and second temperature sensors, and a determination unit to determine, based on the temperatures acquired, a possibility of failure for the first and second tires. The vehicle includes axles on which the tires are mounted. The first and second tires are mounted on an identical axle of the vehicle. Mounting positions of the first and second tires are symmetrical on the identical axle. The determination unit determines that the first tire has a possibility of failure where the temperature of the first tire is greater than a predetermined threshold, and a difference between the temperatures of the first and second tires is greater than a predetermined first temperature threshold.

Abstract: A fiber optic MEMS microphone featuring an electrically deflectable MEMS membrane via a conversion of an optical energy propagating in an optical fiber cable to an electrical energy with a photodiode chip. The fiber optic MEMS microphone includes a MEMS device, the photodiode chip, a voltage, a power adjustable laser beam and a light.

Abstract: Fiber optic terminals and fiber optic networks having variable ratio couplers are disclosed. The fiber optic terminals comprise a shell having a portion of a variable ratio coupler disposed therein. The variable ratio coupler comprises an optical input, a first optical output, a second optical output and a control. The control may be adjusted for changing an output power level between the first optical output and the second optical output.

Abstract: Methods, systems, devices, and products for acoustic detection in a borehole.

Abstract: Pressure sensing guidewires and methods for making and using pressure sensing guidewires are disclosed. An example pressure sensing guidewire may include a tubular member having a proximal region and a housing region. An optical pressure sensor may be disposed within the housing region. The optical pressure sensor may include a sensor body and a deflectable membrane coupled to the sensor body. The deflectable membrane may include a polymer. An optical fiber may be coupled to the sensor body and may extend proximally therefrom. A pressure equalization channel is formed in the optical fiber, the sensor body, or both.

Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: The disclosed principles provide techniques for 3D fabrication of sensing systems embedded inside battery cells and provide cell parameter data for a comprehensive and robust battery management system. The disclosed principles provide online and real-time monitoring battery state-of-health down to the individual cell level of each battery using embedded sensors on one or more of the internal layers of a cell, such as the dielectric separators found in such battery cells. The implementation of the disclosed principles in individual battery cells therefore provides an increased likelihood to mitigate catastrophic failures in batteries. In addition, the disclosed fabrication processes for printing sensors directly on one or more of the components or layers within each individual battery cell significantly reduce manufacturing steps required by conventional battery management systems.

Abstract: A tire repair device with an inflation compressor and a sealant material canister, and method of operation. A pressure gauge determines a tire inflation pressure, and a controller identities a completion of a sealant injection upon a pressure drop measured at the pressure gauge. The controller is configured to automatically shut off the inflation compressor when a tire pressure meets a predetermined inflation value after the pressure drop.

Abstract: A microfluidic strain sensing device for monitoring intraocular pressure. The device has a contact lens and a closed microfluidic network embedded with the contact lens. The network has a volume that is sensitive to an applied strain. The network distinguishes: (i) a gas reservoir containing a gas, (ii) a liquid reservoir containing a liquid that changes volume when the strain is applied, and (iii) a sensing channel able to hold the liquid within the sensing channel. The sensing channel connects the gas reservoir on one end and connects the liquid reservoir on another end. The sensing channel establishes a liquid-gas equilibrium pressure interface and equilibrium within the sensing channel, which would fluidically change as a response to radius of curvature variations on a cornea, or as a response to mechanical stretching and release of the cornea. The liquid-gas equilibrium pressure interface and equilibrium are used for measuring the intraocular pressure.

Abstract: A fiber-optic system for use in optical sensing includes a multicore sensing fiber having at least two cores of which each of the at least two cores has a first core diameter, and a multicore lead-in fiber having at least two cores including a position corresponding with the position of the at least two cores of the multicore sensing fiber. Each of the at least two cores of the multicore lead-in fiber have a second core diameter. The second core diameter is substantially larger than the first core diameter. The system further includes an alignment means for aligning the multicore sensing fiber and the multicore lead-in fiber so that the lead-in fiber and the multicore sensing fiber are configured for coupling radiation between the fibers through the cores.

Abstract: Optical pressure sensor assemblies that can be used with existing catheters and imaging systems. Pressure sensors may be compatible with atherectomy and occlusion-crossing catheters, where intravascular pressure measurements at various vessel locations are needed to determine treatment efficacy. The pressure sensors may employ an optical pressure measurement mechanism using optical interferometry, and may be integrated with existing imaging modalities such as OCT. The pressure sensor assemblies may include a movable membrane that deflects in response to intravascular pressure; an optical fiber that transmits light to the movable membrane and receives light reflected or scattered back from the movable membrane into the fiber; and a processor or controller configured to determine the distance traveled by the light received in the fiber from the movable membrane, where the distance traveled is proportional to the intravascular pressure exerted against the membrane.

Abstract: A method for measuring and computing unsteady loads using unsteady pressure-sensitive paint (uPSP) data includes performing an in-situ calibration using an average of pixels of a portion of an image captured of a surface painted with pressure-sensitive paint. The method also includes dividing an average static pressure by an intensity for each region of interest (ROI) in terms of time to produce a ratioed intensity measuring an intensity fluctuation. The method further includes producing a pressure-time history from the in-situ calibration and the measured intensity fluctuation. The method also includes calculating a fluctuating force by multiplying the produced pressure-time history by an area of pixels in each ROI, and converting a time signal to a frequency, and producing a power spectral density (PSD) to compare frequency content to determine an amount of energy at a certain frequency band.

Abstract: A method for monitoring a liquid-cooled charging cable of a charging station for a traction battery of an electrically operated motor vehicle. Undershooting of a minimum permissible bending radius of the charging cable is detected, and the undershooting of the minimum permissible bending radius is indicated to a user or charge point operator or service employee.

Abstract: A system for detecting a fire or overheating event includes a heat detector, an optical fiber, a photodetector, and a processing unit. The pneumatic heat detector includes a sealed chamber sealed with a diaphragm having an initial position, and the optical fiber is in operable communication with the diaphragm. The optical fiber includes a Fiber Bragg Grating (FBG). The optical signal generator is configured to emit an optical signal with into the optical fiber. The photodetector is configured to receive a reflected optical signal from the FBG. The processing unit is configured to correlate the reflection wavelength of the reflected optical signal with a temperature of the heat detector.

Abstract: A device for measuring a light radiation pressure is provided which includes a torsion balance, a laser, a convex lens, and a line array detector. The laser is configured to emit a first laser beam. The convex lens is located on an optical path of the first laser beam and configured to focus the first laser beam to a surface of the reflector. The line array detector is configured to detect a reflected first laser beam reflected by the reflector. The disclosure also provides a method for measuring the light radiation pressure using the device.

Abstract: A data storage drive includes a rotatable data storage medium, and a head communicatively couplable to the data storage medium. The head includes a temperature sensor and a heater. The data storage drive also includes a ramp for supporting the head when the head is moved away from the data storage medium, and a controller. The controller is configured to obtain first temperature sensor measurement values for different head heater power settings when the head is positioned on the ramp, and is configured to determine an internal pressure of the data storage drive as a function of the first temperature sensor measurement values.

Abstract: In some embodiments, apparatuses and methods are provided herein useful for sensing pressure. In some embodiments, miniature housings are manufactured at ends of optical fibers. In some embodiments, a diamond diaphragm is provided on a hollow housing that receives a fiber optic cable and is sealed to form a Fabry-Perot cavity. In some forms, a plurality of sensors may be manufactured in batch.

Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: Embodiments involve optical waveguides with spongy material for cladding or layers that include compressible gas pockets. The refractive index of the porous cladding material will change when compressed, bent, or stretched. Measurements for pressure, strain, bending, etc., may be obtained by monitoring the signal degradation and/or escape of radiant energy, e.g., IR, etc., from the core and out through the spongy cladding, where it may be picked up by a neighboring core. Optical waveguides configured as fibers may be easily sewn to stretchable materials, such as athletic tape, fabrics used in umbrellas, balloons, fabrics used in clothing, etc., to meet a robust number of applications.

Abstract: Embodiments relate to the design and use of a low profile ablation catheter with a liquid core for use in laser ablation removal of arterial plaque blockages to restore blood flow.

Abstract: A medical device system may include a guidewire including a distal pressure sensor and a proximal end. A connector cable may be coupled to the proximal end of the guidewire and may have a proximal end. A signal conditioning unit may be coupled to the proximal end of the connector cable. One or more of the guidewire, the connector cable, and the signal conditioning unit may include an optical fiber having a core with a tapered outer diameter.

Abstract: The present document relates to a pressure sensor comprising a structural element, the structural element comprising a first and second structural part. The sensor further comprises a first cavity being in fluid connection with an exterior of the sensor for establishing a first pressure which is dependent on an external pressure in the first cavity and a second cavity configured to be at a second pressure in use. A deformable structure is deformable dependent on a pressure difference between the first pressure and the second pressure. The sensor comprises a fiber including an intrinsic fiber optic sensor fixed to the structural element and to the deformable structure for providing an optical sensor signal dependent on said pressure difference.

Abstract: A shallow water anchor and related methods are provided. The shallow water anchor includes a four-bar linkage and a hydraulic actuator for actuating the four-bar linkage. An anchoring element is connected to the four-bar linkage. A hydraulic control arrangement operates the hydraulic actuator to transition the hydraulic actuator between stowed and deployed positions and vice versa. The shallow water anchor can incorporate a controller which monitors a current limit, a pressure limit, or both to perform a variety of anchoring functions.

Abstract: Disclosed are an apparatus for measuring a displacement using a fiber Bragg grating sensor, which is applied to a strain sensor using the fiber Bragg grating sensor, and a method of controlling sensitivity and durability of the same. The apparatus includes: a case forming an external appearance; third and fourth optical fibers having mutually different numbers of strands and installed in the case while being spaced apart from each other by a predetermined interval; and a connection unit installed between the third and fourth optical fibers and fixed at a predetermined position by tension applied to the third and fourth optical fibers, wherein the fiber Bragg grating sensor is installed to one selected from the pair of optical fibers having mutually different numbers of strands, so that measurement sensitivity and durability are controllable.

Abstract: Fiber optical Fabry-Perot flow test device with local bending diversion structure, having an inlet flange, a test tube and an outlet flange, with both a fiber optical Fabry-Perot pressure sensor at high-pressure-side and a fiber optical Fabry-Perot pressure sensor at low-pressure-side, which are fixedly connected to the test tube through an auxiliary connecting device.

Abstract: The present invention provides a sensor system for measuring a parameter (e.g. volume, temperature or pressure) of a target, the system comprising a diaphragm, a sensor for measuring the axial spacing between the sensor and the diaphragm, and an axially adjustable mount. The mount has a first axial end for mounting the diaphragm which is axially movable relative to the sensor and an opposing, second axial end which is axially fixed relative to the sensor. The diaphragm and mount define a chamber for receiving the target or for being received within the target. In use, the axial spacing between the first axial end and the second axial end of the mount and thus the axial spacing between the diaphragm and sensor varies as a result of a change in the parameter differential across the diaphragm.

Abstract: The purpose of the present invention is to provide a bonded structure, a method for manufacturing the same, and a bonding state detection method which are capable of determining whether or not members are bonded together appropriately. A bonded structure 10 includes a laminated sheet 12A, a laminated sheet 12B, an adhesive 14 that bonds the laminated sheet 12A and the laminated sheet 12B together, and a distributed optical fiber 16 sandwiched between the laminated sheet 12A and the laminated sheet 12B. The cross-sectional shape of the distributed optical fiber 16 is deformed in accordance with the bonding state.

Abstract: An optical pressure sensor is disclosed having a pressure sensing optical cavity. A temperature sensing optical cavity at the sensing head is used by an interrogator to correct a pressure signal for effects of temperature. The optical cavities may be, for example, Fabry Perot cavities in the sensor head.

Abstract: The application describes methods and apparatus for seismic monitoring using fiber optic distributed acoustic sensing (DAS). The method involves interrogating a first optical fiber (102) deployed in an area of interest to provide a distributed acoustic sensor comprising a plurality of longitudinal sensing portions of fiber and also monitoring at least one geophone (107) deployed in the area of interest. The signal from the at least one geophone is analyzed to detect an event of interest (105). If an event of interest is detected the data from the distributed acoustic sensor acquired during said event of interest is recorded. The geophone may be co-located with part of the sensing fiber and in some embodiments may be integrated (307) with the sensing fiber.

Abstract: An electronic device includes an input surface area for receiving a force applied by a user and one or more optical waveguides that include Bragg gratings. The optical waveguide or waveguides is operatively affixed to the input surface area. At least one light source is optically coupled to the optical waveguide or waveguides. At least one wavelength interrogator is coupled to the optical waveguide or waveguides.

Abstract: A pressure detecting apparatus made by 3D printing technologies being able to be used in dangerous areas is provided. It mainly comprises a light source, a processor, a coupler, and at least one pressure transducer. The pressure transducer comprises a main body and a fiber grating. The fiber grating comprises a fiber Bragg grating sensor, and the fiber grating is fixed on the main body and covers the fiber Bragg grating sensor. When the main body is placed in a fluid area, the fluid would flow through the opening to deform the strain layer and generate a strain variation on the fiber Bragg grating sensor to cause a signal variation in the reflection frequency spectrum. The coupler is configured to couple to the light source and the pressure transducer to decode the signal variation into pressure parameters.

Abstract: A removable material is deposited or otherwise applied to a flat substrate surface in a pattern corresponding to desired corrugations in a membrane, e.g., a deflection diaphragm. The applied material serves as a scaffold for a polymeric material, which is applied thereover, and following cure or hardening, the polymeric material is removed to form a finished corrugated membrane.

Abstract: Some embodiments of an infusion pump system may include an occlusion sensor that can be used to detect when an occlusion exists in the fluid path between the medicine reservoir and the infusion site on the user's skin. Such an occlusion may occur, for example, when the fluid flow line (e.g., a cannula, infusion set tubing, or the like) is kinked. If the medicine dispensation path to the user is occluded, the user may receive no dosage or a lower dosage of the medicine. As such, the occlusion sensor can be used to indicate when the fluid is flowing or not flowing, thereby permitting the infusion pump system to communicate an alarm to the user if an occlusion exists.

Abstract: An optical sensor is disclosed for measuring pressure and/or temperature. The optical sensor is adapted for use in high temperature environments, such as gas turbines and other engines. The optical sensor comprises an optical assembly having a sensor element, a spacer and a lens arranged along the optical axis. The sensor element is spaced from the lens by the spacer. An optical fiber is coupled to the optical assembly for illuminating the sensor element. The optical assembly is resiliently mounted in a housing such that the optical assembly is insulated from shock to the housing. There is also disclosed a method of assembling the optical sensor.

Abstract: The present invention relates to a high stable fiber fabry-perot pressure sensor with glue-free packing and its fabrication method. The sensor includes a sensor head, a sensor body with a through-hole in the axial direction and a optical fiber. The sensor head is a 4-layer structure, which includes the first silicon wafer, the first Pyrex glass wafer, the second silicon wafer and the second Pyrex glass wafer. The rear surface of the first silicon wafer forms the first reflecting surface of the fabry-perot (F-P) cavity, and the second silicon wafer provides the second reflecting surface for the F-P cavity. The second Pyrex glass wafer is welded together with the sensor body. The optical fiber is fixed in the sensor body by a CO2 laser welding to achieve the glue-free packing. When the external pressure is applied to deform the first layer silicon wafer, the F-P cavity length will change.

Abstract: An apparatus and method for finding part position relations of parts of mechanical and opto-mechanical machining and quality control systems, and for recognizing these parts, is disclosed. The present invention relies on optical contactless sensing technology, with recording of optical fiducial patterns and therefrom determining positions close to the work positions without physical contact. Part positions of machines are determined by associating or mechanically integrating fiducial patterns (1) with key parts, and optically detecting the images of these patterns. Part positions and displacements according to given part position finder (6) strategies are found, by associating fiducial pattern images (14) and machine position data (17) to parts that are members of a part geometry relation (15), and under part displacement constraints (16), finding given part positions or displacements (18).

Abstract: A holographic pressure sensing apparatus includes a first optical fiber with a diffractive element at its end face, and a light-coupling component for receiving from the first optical fiber end face first and second images respectively formed by interaction with the diffractive element of a first light of a first wavelength and a second light of a second wavelength. Displacement of the light-coupling component, toward or away from the first optical fiber end face, will adjust an overlap of the first and second images, such that a change in a measurement of said overlap will indicate a change of the pressure in the fluid surrounding the casing.

Abstract: Ultra-miniature surface-mountable optical pressure sensor is constructed on an optical fiber. The sensor design utilizes an angled fiber tip which steers the optical axis of the optic fiber by 90°. The optical cavity is formed on the sidewall of the optic fiber. The optical cavity may be covered with a polymer-metal composite diaphragm to operate as a pressure transducer, Alternatively, a polymer-filled cavity may be constructed which does not need a reflective diaphragm. The sensor exhibits a sufficient linearity over the broad pressure range with a high sensitivity. The sensitivity of the sensor may he tuned by controlling the thickness of the diaphragm. Methods of batch production of uniform device-to-device optical pressure sensors of co-axial and cross-axial configurations are presented.

Abstract: An optical pressure sensor is disclosed having a pressure sensing optical cavity. A temperature sensing optical cavity at the sensor head is used by an interrogator to correct a pressure signal for effects of temperature. The optical cavities may be, for example, Fabry Perot cavities in the sensor head.

Abstract: Various embodiments include apparatus and methods to measure pressure using an optical fiber. The optical fiber can be structured with fiber Bragg gratings arranged along the optical fiber. Optical signals can be transmitted through the optical fiber, where the optical signals have a wavelength of a slow-light peak of a respective one of the fiber Bragg gratings. Signals resulting from the optical signals transmitted through the optical fiber can be detected and a value of pressure from the detected signals can be determined.

Abstract: A pressure sensing system includes a pressure sensor, an optical fiber in operable communication with the pressure sensor, and a body having a diaphragm integrally formed therein and separated a distance from the optical fiber.