Measurement instrument, measurement method, measurement system, and program

Patent metadata

Field	Value
Publication number	US-10203350-B2
Application number	US-201615272775-A
Country	US
Kind code	B2
Filing date	Sep 22, 2016
Priority date	Oct 2, 2015
Publication date	Feb 12, 2019
Grant date	Feb 12, 2019

Abstract

An acquisition unit acquires the width-direction acceleration and the vertical-direction acceleration of a surface of a structure on which a moving object moves from an acceleration sensor provided in the structure on which the moving object moves. A displacement computation unit computes the vertical-direction displacement of the structure on the basis of the vertical-direction acceleration. A correlation determination unit determines the correlation between the width-direction acceleration and the vertical-direction displacement. A movement detection unit detects the movement of the moving object on the structure on the basis of the correlation.

First claim

What is claimed is:

1. A movable object information obtaining system comprising:
an acceleration sensor that is disposed on a side of a bridge deck, the bridge deck extending along a plane having a Y axis and a Z axis perpendicular to each other, a movable object being movable on the bridge deck in a direction along the Y axis, the bridge deck being movable along an X axis perpendicular to the Y and Z axes when the movable object moves on the bridge deck, the acceleration sensor being configured to detect vertical direction acceleration along the X axis and to detect width direction acceleration along the Z axis;
a memory configured to store computer-readable instructions; and
a processor configured to execute the computer-readable instructions so as to:
obtain sensor data corresponding to the vertical direction acceleration and the width direction acceleration from the acceleration sensor;
filter out a frequency band including a natural resonance frequency component of the bridge deck from the sensor data so as to generate filtered sensor data;
calculate vertical direction displacement based on the vertical direction acceleration detected by the acceleration sensor;
determine a correlation between the calculated vertical direction displacement and the width direction acceleration detected by the acceleration sensor;
detect movement of the movable object on the bridge deck based on the determined correlation; and
obtain movable object information of the movable object based on the filtered sensor data and the vertical direction displacement,

wherein the acceleration sensor is configured to detect a Z axis component of gravity acceleration due to inclination of a surface of the bridge deck when the movable object moves on the bridge deck, and the Z axis component of gravity acceleration corresponds to the width direction acceleration, and
the acceleration sensor is configured to detect the vertical direction acceleration along the X axis due to the inclination of the surface of the bridge deck caused by a weight of the movable object.

2. The movable object information obtaining system according to claim 1 ,
wherein the processor is configured to calculate covariance of the calculated vertical direction displacement and the width direction acceleration so as to determine the correlation.

3. The movable object information obtaining system according to claim 1 ,
wherein the processor is configured to obtain characteristic information of a waveform of the width direction acceleration when the processor detects the movement of the movable object on the bridge deck, and
the waveform is approximated based on a wave crest value, a wave amplitude, a waveform coefficient, and a time at which the movable object moves on the bridge deck.

4. The movable object information obtaining system according to claim 2 ,
wherein the processor is configured to obtain characteristic information of a waveform of the width direction acceleration when the processor detects the movement of the movable object on the bridge deck, and
the waveform is approximated based on a wave crest value, a wave amplitude, a waveform coefficient, and a time at which the movable object moves on the bridge deck.

5. The movable object information obtaining system according to claim 1 ,
wherein the processor is configured to obtain characteristic information of a waveform of the vertical direction displacement when the processor detects the movement of the movable object on the bridge deck, and
the waveform is approximated based on a wave crest value “h u ,” a wave amplitude “w u ,” a waveform coefficient “a,” and a time “t 0 ” at which the movable object moves on the bridge deck.

6. The movable object information obtaining system according to claim 5 ,
wherein the waveform is approximated by the following expression:

u
⁡

(
t
)

=

h
u

·

a

-

(

t
-

t
0

w
u

)

2

.

7. The movable object information obtaining system according to claim 6 ,
wherein the waveform is obtained by approximating at a pre-time that is before the time “t 0 ” and at a post-time that is after the time “t 0 .”

8. The movable object information obtaining system according to claim 1 ,
wherein the processor is configured to calculate an envelope curve of the the vertical direction acceleration,
the processor is configured to detect vibration of the bridge deck based on the calculated envelope curve, and
the processor is configured to determine the correlation when the processor detects the vibration of the bridge deck.

9. The movable object information obtaining system according to claim 2 ,
wherein the processor is configured to calculate an envelope curve of the the vertical direction acceleration,
the processor is configured to detect vibration of the bridge deck based on the calculated envelope curve, and
the processor is configured to determine the correlation when the processor detects the vibration of the bridge deck.

10. A method of obtaining movable object information for causing a processor to execute computer-readable instructions stored in a memory, the method comprising executing on the processor the steps of:
detecting vertical direction acceleration along an X axis by an acceleration sensor that is disposed on a side of a bridge deck, the bridge deck extending along a plane having a Y axis and a Z axis perpendicular to each other, a movable object being movable on the bridge deck in a direction along the Y axis, the bridge deck being movable along the X axis perpendicular to the Y and Z axes when the movable object moves on the bridge deck;
detecting width direction acceleration along the Z axis by the acceleration sensor;
obtaining sensor data corresponding to the vertical direction acceleration and the width direction acceleration from the acceleration sensor;
filtering out a frequency band including a natural resonance frequency component of the bridge deck from the sensor data so as to generate filtered sensor data;
calculating vertical direction displacement based on the vertical direction acceleration detected by the acceleration sensor;
calculating covariance of the calculated vertical direction displacement and the width direction acceleration;
determining a correlation between the calculated vertical direction displacement and the width direction acceleration based on the covariance;
detecting a movement of the movable object on the bridge deck based on the determined correlation; and
obtaining movable object information of the movable object based on the filtered

Assignees

• Seiko Epson Corp

Inventors

• Kobayashi Yoshihiro

Classifications

• G01P13/00 Primary

  Indicating or recording presence, absence, or direction, of movement (electric switches H01H; counting moving objects G06M7/00) · CPC title

• G01P3/66

  using electric or magnetic means (G01P3/80 takes precedence; measuring short time intervals G04F8/00, G04F10/00) · CPC title