# US 10,768,145 B2 · Measurement apparatus, attenuation characteristic calculation method, program, and measurement system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,768,145 B2 - Document ID: US10768145B2 - Status: Granted - Kind: B2 - Application number: 15/381,547 - Filed: 2016-12-16 - Published: 2017-06-29 - Granted: 2020-09-08 - Earliest claimed: 2015-12-28 - Assignees: Seiko Epson Corporation - Applicants: Seiko Epson Corporation - Inventors: Yoshihiro Kobayashi - Web page: https://patentgrep.com/patent/US10768145B2 ## CPC - G01N 29/11: by measuring attenuation of acoustic waves - G01H 1/06: Frequency - G01M 5/0008: {of bridges} - G01M 5/0066: {by exciting or detecting vibration or acceleration (vibration testing of structures G01M7/00)} - G01N 29/12: by measuring frequency or resonance of acoustic waves {(measuring frequency or resonant frequency of mechanical vibrations or acoustic waves in general G01H1/06, G01H3/04, G01H13/00; acoustic resonators G10K11/04; vibration or shock testing of structures G01M7/00)} - G01N 29/14: using acoustic emission techniques {(echo of particles G01N29/046; measuring mechanical vibrations or acoustic waves in solids in general G01H1/00)} - G01N 29/42: by frequency filtering {or by tuning to resonant frequency} - G01N 29/44: Processing the detected response signal {, e.g. electronic circuits specially adapted therefor (digital signal processing per se G06F17/00)} - G01N 29/4418: {with a model, e.g. best-fit, regression analysis} - G01N 29/4472: {Mathematical theories or simulation} - G01P 3/02: Devices characterised by the use of mechanical means - G01P 3/64: Devices characterised by the determination of the time taken to traverse a fixed distance - G01N 2291/015: Attenuation, scattering - G01N 2291/0258: Structural degradation, e.g. fatigue of composites, ageing of oils - G01N 2291/0289: Internal structure, e.g. defects, grain size, texture - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01H: MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR - G01P: MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT (measuring or recording blood flow A61B5/02, A61B8/06; monitoring speed or deceleration of electrically-propelled vehicles B60L3/00; vehicle lighting systems adapted to indicate speed B60Q1/54; determining position or course in navigation, measuring ground distance in geodesy or surveying G01C; combined measuring devices for measuring two or more variables of movement G01C23/00; measuring velocity of sound G01H; measuring velocity of light G01J7/00; measuring direction or velocity of solid objects by reception or emission of radiowaves or other waves and based on propagation effects, e.g. Doppler effect, propagation time, direction of propagation, G01S; measuring speed of nuclear radiation G01T; measuring acceleration of gravity G01V; {measuring or recording the speed of trains B61L23/00; speed indicators incorporated in motor vehicles B60K35/00; measuring frequency or phase G01R; traffic control G08G}) ## Abstract A conversion section converts a change in signal information outputted from a vibration detector provided on a structural body from the change in the function of time into the change in the function of the distance between a moving object that moves on the structural body and the vibration detector. An attenuation characteristic calculation section calculates an attenuation characteristic of the structural body based on the signal information so converted as to represent the change in the function of the distance. ## Claims ### Claim 1 A measurement apparatus for measuring abnormalities in a structural body and performing a structural inspection of the structural body, the measurement apparatus comprising: conversion circuitry that receives signal information output from a vibration detector and converts a change in the signal information as provided in a first position on the structural body from a change in the function of time into a change in the function of a distance between a moving object that moves on the structural body and the vibration detector, wherein the signal information indicates an attenuation of a vibration acceleration signal generated by the vibration detector caused by an impact of the moving object, and wherein the attenuation corresponds to a decrease in an amplitude of the vibration acceleration signal as a distance between the vibration detector and the moving object increases; attenuation characteristic calculation circuitry that calculates an attenuation coefficient of the attenuation of the vibration acceleration signal through the structural body based on the signal information so converted as to represent the change in the function of the distance, wherein the attenuation characteristic calculation circuitry calculates the attenuation coefficient using amplitudes, as measured by the vibration detector, of the vertical acceleration signal as caused by the impact of the moving object in a plurality of second positions different from the first position; estimation circuitry that estimates, for the structural inspection of the structural body, an occurrence of an abnormality of the structural body based on the attenuation coefficient; and output circuitry that outputs the occurrence of abnormality. ### Claim 2 (depends on 1) The measurement apparatus according to claim 1, further comprising speed calculation circuitry that calculates a speed of the moving object, wherein the conversion circuitry converts a change in the signal information outputted from the vibration detector from the change in the function of time into the change in the function of the distance by using the speed of the moving object. ### Claim 3 (depends on 1) The measurement apparatus according to claim 1, wherein the vibration detector is provided on a side end portion of the structural body, which extends along a restriction direction of a movement direction restrictor that restricts a movement direction of the moving object, and in a central portion of the side end portion in a direction along the restriction direction. ### Claim 4 (depends on 1) The measurement apparatus according to claim 1, wherein the signal information is information on vertical acceleration or width-direction acceleration of a surface of the structural body on which the moving objects travels. ### Claim 5 (depends on 1) The measurement apparatus according to claim 1, wherein the conversion circuitry converts the signal information having a predetermined frequency component and a frequency component due to bending of the structural body resulting from a load of the moving object into the change in the function of the distance, wherein the predetermined frequency component excludes a frequency component due to natural resonance of the structural body. ### Claim 6 (depends on 1) The measurement apparatus according to claim 1, wherein the attenuation characteristic calculation circuitry calculates the attenuation coefficient of the structural body based on information on a distance-dependent waveform of the signal information and information on a waveform that is expressed by an attenuation model of the structural body and attenuates with a distance. ### Claim 7 (depends on 1) The measurement apparatus according to claim 1, wherein the conversion circuitry extracts the signal information produced when the moving object moves on the structural body based on entrance and exit of the moving object into and out of the structural body detected by a detector and converts the signal information into the change in the function of the distance. ### Claim 8 An attenuation characteristic calculation method for measuring abnormalities in a structural body and performing a structural inspection of the structural body, the method comprising: converting a change in signal information outputted from a vibration detector provided in a first position on the structural body from the change in the function of time into the change in the function of a distance between a moving object that moves on the structural body and the vibration detector, wherein the signal information indicates an attenuation of a vibration acceleration signal generated by the vibration detector caused by an impact of the moving object, and wherein the attenuation corresponds to a decrease in an amplitude of the vibration acceleration signal as a distance between the vibration detector and the moving object increases; calculating an attenuation coefficient of the attenuation of the vibration signal through the structural body based on the signal information so converted as to represent the change in the function of the distance, wherein the attenuation coefficient is calculated using amplitudes, as measured by the vibration detector, of the vertical acceleration signal as caused by the impact of the moving object in a plurality of second positions different from the first position; estimating, for the structural inspection of the structural body, an occurrence of an abnormality of the structural body based on the attenuation coefficient; and outputting the occurrence of abnormality. ### Claim 9 A program stored on a non-transitory computer readable storage medium that causes a computer to perform, for measuring abnormalities in a structural body and performing a structural inspection of the structural body: converting a change in signal information outputted from a vibration detector provided in a first position on the structural body from the change in the function of time into the change in the function of a distance between a moving object that moves on the structural body and the vibration detector, wherein the signal information indicates an attenuation of a vibration acceleration signal generated by the vibration detector caused by an impact of the moving object, and wherein the attenuation corresponds to a decrease in an amplitude of the vibration acceleration signal as a distance between the vibration detector and the moving object increases; calculating an attenuation coefficient of the attenuation of the vibration acceleration signal through the structural body based on the signal information so converted as to represent the change in the function of the distance, wherein the attenuation coefficient is calculated using amplitudes, as measured by the vibration detector, of the vertical acceleration signal as caused by the impact of the moving object in a plurality of second positions different from the first position; estimating, for the structural inspection of the structural body, an occurrence of an abnormality of the structural body based on the attenuation coefficient; and outputting the occurrence of abnormality. ### Claim 10 A measurement system for measuring abnormalities in a structural body and performing a structural inspection of the structural body, the measurement system comprising: a vibration detector provided in a first position on the structural body; and a measurement apparatus including conversion circuitry that converts a change in signal information outputted from the vibration detector from the change in the function of time into the change in the function of a distance between a moving object that moves on the structural body and the vibration detector, wherein the signal information indicates an attenuation of a vibration acceleration signal generated by the vibration detector caused by an impact of the moving object, and wherein the attenuation corresponds to a decrease in an amplitude of the vibration acceleration signal as a distance between the vibration detector and the moving object increases, attenuation characteristic calculation circuitry that calculates an attenuation coefficient of the attenuation of the vibration acceleration signal through the structural body based on the signal information so converted as to represent the change in the function of the distance, wherein the attenuation characteristic calculation circuitry calculates the attenuation coefficient using amplitudes, as measured by the vibration detector, of the vertical acceleration signal as caused by the impact of the moving object in a plurality of second positions different from the first position, estimation circuitry that estimates, for the structural inspection of the structural body, an occurrence of an abnormality of the structural body based on the attenuation coefficient, and output circuitry that outputs the occurrence of abnormality.