A soft, flexible microtube sensor and associated method of sensing force are described. A liquid metallic alloy is sealed within a microtube as thin as a strand of human hair to form the physical force sensing mechanism. The sensor is hardly distinguishable with the naked eye, and can be used for the continuous biomonitoring of physiological signals, such as unobtrusive pulse monitoring. Also described is a method of fabricating the microtube sensor and wearable devices incorporating one or more microtube sensors.

A system for sensing microbends and micro-deformations in three-dimensional space is based upon a distributed length optical fiber formed to include a group of offset cores disposed in a spiral configuration along the length of the fiber, each core including a fiber Bragg grating that exhibits the same Bragg wavelength. A micro-scale local deformation of the multicore fiber produces a local shift in the Bragg wavelength, where the use of multiple cores allows for a complete micro-scale modeling of the local deformation. Sequential probing of each core allows for optical frequency domain reflectometry (OFDR) allows for reconstruction of a given three-dimensional shape, delineating location and size of various microbends and micro-deformations.

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.

A tension transducer causes macro-bends in a single-mode fiber sensing line when a utility pole to which it is connected experiences an overturning moment. The device uses a trough shaped geometry to hold and support the single-mode sensing fiber, where an inelastically flexible hinge at the bottom, and a cinching mechanism at the top which connects to a pole mounting plate, combine to depress offset grooves on the inside of the trough walls into the fiber cable, to create a macro-bend in the single mode fiber which results in a detectable signal identifier on a time-domain laser reflectometry interrogation trace of the fiber sensor line. The device's connection to the pole mounting plate is designed to break away and disconnect at a tension value that would exceed the tensile strength of the fiber sensor cable, while still providing sufficient tension transfer to the device to close the trough about the hinge and cause a macro-bend in the single-mode fiber cable.

A fiber-optic sensor matt detects movements of a person on the matt that cause microbending of a fiber-optic cable that is arranged into a symmetric pair of radial ring groups within the matt. There are no cross-over points or overlapping of the fiber-optic cable within the symmetric pair of radial ring groups that could cause fiber wear and noisy readings. Microbending of the fiber-optic cable pressed into a mesh modulates the light intensity received, which is analyzed to extract both respiration and heart BallistoCardioGram (BCG) waveforms by convolution with Daubechies dB5 wavelet and scaling functions. The reconstructed level-4 detail waveform is output as the extracted BCG, while the reconstructed level-6 approximation waveform is output as the extracted respiration waveform. Respiration and heart rates and variations can be generated from the extracted waveforms. An integrated Fast Wavelet Transform (FWT) using dB5 wavelet thus generates both respiration rate and heart rate.

The present invention concerns apparatus (1) for obtaining distributed pressure measurements in a wellbore (2), the apparatus (1) comprising: a flexible rod (10; 110) arranged to be disposed in the wellbore (2); and an elongate sensing member (15; 115) extending along the rod, the sensing member comprising at least one optical sensing fibre member (16; 116) arranged to afford a continuous length of sensing capability, wherein the sensing member extends in a groove formed in the exterior surface of the rod.

A tension transducer causes macro-bends in a single-mode fiber sensing line when a utility pole to which it is connected experiences an overturning moment. The device uses a trough shaped geometry to hold and support the single-mode sensing fiber, where an inelastically flexible hinge at the bottom, and a cinching mechanism at the top which connects to a pole mounting plate, combine to depress offset grooves on the inside of the trough walls into the fiber cable, to create a macro-bend in the single mode fiber which results in a detectable signal identifier on a time-domain laser reflectometry interrogation trace of the fiber sensor line. The device's connection to the pole mounting plate is designed to break away and disconnect at a tension value that would exceed the tensile strength of the fiber sensor cable, while still providing sufficient tension transfer to the device to close the trough about the hinge and cause a macro-bend in the single-mode fiber cable.

This invention relates a biomarker detection system, for detecting cancer biomarkers using optical heterodyning. The system includes a tunable laser configured to produce a plurality of laser beams of at least two frequencies, a pair of optical fibers coated with gold nanoparticles and functionalized with an antibody is configured to undergo a change of fiber surface of each optical fiber by adsorbing molecules of an analyte on a surface of the antibody, modify a reflection of the plurality of laser beams inside a fiber core of the each optical fiber when the each optical fiber is bent, and create an audible beat frequency; and perform spectral analysis. A frequency spectrum analyzer configured to provide a composition information of the adsorbed molecules based on a spectral analysis of the beat frequency.

A soft, flexible microtube sensor and associated method of sensing force are described. A liquid metallic alloy is sealed within a microtube as thin as a strand of human hair to form the physical force sensing mechanism. The sensor is hardly distinguishable with the naked eye, and can be used for the continuous biomonitoring of physiological signals, such as unobtrusive pulse monitoring. Also described is a method of fabricating the microtube sensor and wearable devices incorporating one or more microtube sensors.

A fiber-optic sensor matt detects movements of a person on the matt that cause microbending of a fiber-optic cable that is arranged into a symmetric pair of radial ring groups within the matt. There are no cross-over points or overlapping of the fiber-optic cable within the symmetric pair of radial ring groups that could cause fiber wear and noisy readings. Microbending of the fiber-optic cable pressed into a mesh modulates the light intensity received, which is analyzed to extract both respiration and heart BallistoCardioGram (BCG) waveforms by convolution with Daubechies dB5 wavelet and scaling functions. The reconstructed level-4 detail waveform is output as the extracted BCG, while the reconstructed level-6 approximation waveform is output as the extracted respiration waveform. Respiration and heart rates and variations can be generated from the extracted waveforms. An integrated Fast Wavelet Transform (FWT) using dB5 wavelet thus generates both respiration rate and heart rate.