A method for estimating structural vibration in real time includes steps described below. A to-be-estimated measuring point of a to-be-measured structure is acquired, and at least one target measuring point associated with the to-be-estimated measuring point is determined; coordinates corresponding to each target measuring point of the at least one target measuring point, a target mode corresponding to the each target measuring point and a target vibration parameter corresponding to the each target measuring point are determined; a mode vibration parameter of the to-be-estimated measuring point and an interpolation vibration parameter of the to-be-estimated measuring point are determined based on the to-be-estimated measuring point and in combination with the target mode, the target vibration parameter and the coordinates of the each target measuring point; and an estimated vibration parameter of the to-be-estimated measuring point is determined according to the mode vibration parameter and the interpolation vibration parameter.

An optical fiber sensing system according to the present disclosure includes: an optical fiber (10) provided along a road R to detect vibrations; a detection unit (21) configured to detect a vibration pattern of a vibration caused by a traffic accident that has occurred on the road R from optical signals received from the optical fiber (10); and an estimation unit (22) configured to estimate a situation of the traffic accident based on the vibration pattern.

Aspects of the present disclosure describe distributed fiber optic sensing (DFOS) systems, methods, and structures that advantageously sense/monitor intra-data center operations using self-coherent detection. Advantageously, sensing signal(s) and data signal(s) are optically multiplexed such that the sensing signal(s) are generated and detected using the same optoelectronic components as data generation and detection while requiring only minimal changes to transponder arrangements and no additional bandwidth to digital-to-analog converters (DAC) or analog-to-digital converters (ADC).

A sensor includes at least one optical waveguide and an optical reflector optically coupled to the at least one optical waveguide. The optical reflector includes a first substrate portion configured to reflect a first portion of a light beam back to the at least one optical waveguide and a diaphragm configured to reflect a second portion of the light beam back to the at least one optical waveguide. The diaphragm is responsive to a perturbation by moving relative to the first substrate portion. The light beam is centered on a region between the first substrate portion and the diaphragm.

A measurement terminal includes: a storage that stores, for each of one or more inspection objects, setting information including a parameter related to a feature of an inspection and an abnormality; a processor; and a memory having instructions that, when executed by the processor, cause the processor to perform operations. The operations include: acquiring audio data of sound from an inspection object; deriving, based on the setting information of a corresponding one of the one or more inspection objects, a required time for acquiring the audio data of sound from the inspection object to be used for determining a presence or absence of the abnormality in the inspection object; and determining the presence or absence of the abnormality in the inspection object based on the audio data of sound from the inspection object for the derived required time.

This disclosure is related to devices, systems, and techniques for determining an acceleration. For example, an accelerometer system includes a resonator and a light-emitting device configured to generate, based on an error signal, an optical signal. Additionally, the accelerometer includes a modulator configured to receive the optical signal, generate a modulated optical signal responsive to receiving the optical signal, and output the modulated optical signal to the resonator. A photoreceiver receives a passed optical signal from the resonator, where the passed optical signal indicates a resonance frequency of the resonator. Additionally, the photoreceiver receives a reflected optical signal from the resonator. The photoreceiver generates one or more electrical signals based on the passed optical signal and the reflected optical signal. Processing circuitry generates the error signal and determines the acceleration based on the one or more electrical signals.

Distributed fiber optic sensing (DFOS) and artificial intelligence (AI) systems and methods for performing utility pole hazardous event localization that advantageously identify a utility pole that has undergone a hazardous event such as being struck by an automobile or other detectable impact. Systems and methods according to aspects of the present disclosure employ machine learning methodologies to uniquely identify an affected utility pole from a plurality of poles. Our systems and methods collect data using DFOS techniques in telecommunication fiber optic cable and use an AI engine to analyze the data collected for the event identification. The AI engine recognizes different vibration patterns when an event happens and advantageously localizes the event to a specific pole and location on the pole with high accuracy. The AI engine enables analyses of events in real-time with greater than 90% accuracy.

Systems and methods for reducing work conflicts is provided. The method includes receiving a vibrational signal from a utility pole; identifying a location and type of field work on the utility pole from one or more features of the vibrational signal utilizing a trained neural network; and communicating the location and type of field work to a third party.

A system, apparatus, and method for demodulation of a fiber optic sensor is provided. An aspect of the system provides an optical fiber, a laser, a phase modulator configured to be coupled to the optical fiber, and a sensor. The laser emits a laser beam into the optical fiber. The phase modulator receives the laser beam from the laser and directs the laser beam to the sensor. The sensor includes a coiled portion of the optical fiber, uncoiled segments adjacent the coiled portion, and at least two fiber Bragg gratings configured to be coupled to opposite uncoiled segments adjacent the coiled portion of the optical fiber. The sensor system may further include a photodetector configured to receive a reflected portion of the laser beam from the sensor. The reflected portion is divided into at least two paths where at least two sub-outputs are generated for demodulation and sensing.

The present invention discloses a grating enhanced distributed vibration demodulation system based on three-pulse shearing interference, comprising: a laser device, a pulse optical modulator, a three-pulse generation polarization-maintaining structure, a first erbium-doped fiber amplifier, a first optical circulator, a fiber grating array, a second erbium-doped fiber amplifier, a second optical circulator, a three-in-three optical coupler, a first Faraday rotator mirror, a second Faraday rotator mirror, and a four-channel data acquisition card, On the basis of a distributed fiber grating vibration sensing system, three-pulse dislocation interference and three-in-three optical coupler digital phase demodulation technologies are adopted, XX and XY pulses are utilized to complement interference visibility, and demodulation is performed by selecting a better path, so that polarization fading resistance and interference signal high visibility in the distributed fiber grating vibration sensing system are realized.