Method for simultaneously measuring bending curvature and bending direction

A technology of bending direction and measurement method, which is applied in the direction of measuring devices, instruments, optical devices, etc., can solve the problems that have not been discovered and can not realize the discrimination, and achieve the effect of low cost and small size

Inactive Publication Date: 2005-10-19
SHANGHAI JIAO TONG UNIV
View PDF0 Cites 18 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method can only realize the discrimination of two symmetrical bending directions (ie, upward bending or downward bending) and cannot realize the discrimination of any b

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for simultaneously measuring bending curvature and bending direction
  • Method for simultaneously measuring bending curvature and bending direction
  • Method for simultaneously measuring bending curvature and bending direction

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0026] In order to better understand the technical solution of the present invention, further description will be made below in conjunction with the accompanying drawings and specific embodiments.

[0027] The principle diagram of the simultaneous measurement method of bending curvature and bending direction proposed by the present invention is as follows figure 1 shown. The scheme is mainly based on the high frequency CO 2 The bending characteristics of long-period fiber gratings written by laser pulses have obvious bending direction dependence. The measurement steps of the specific example are as follows:

[0028] (1) use figure 2 The shown bending characteristic measurement device measures the bending sensitivity of the resonant wavelength and loss peak amplitude of the LPFG to bending in different directions. LPFG represents the measured long-period fiber grating; P represents the applied pressure; l represents the length of the bent optical fiber (grating), that is, ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The simultaneous measurement method of bending curvature and bending direction includes first measuring long period fiber grating bending characteristic and drawing the bending sensitivity curve of resonance wavelength of long period fiber grating LPFGA and LPFGB vs circumferential direction in 360 deg; cascading LPFGA and LPFGB and LPFGC with unimodal fibers and embedding into the measured engineering structure; measuring variation in resonance wavelength; calculating bending curvature; and judging the bending direction of the measured engineering structure based on the variation in LPFGA and LPFGB resonance wavelength and the bending curvature and through comparison with the bending sensitivity curve. The present invention realizes the simultaneous measurement method of bending curvature and bending direction of engineering structure, and the sensor is small, low in cost, compatible with fiber and easy in embedding into the measured engineering structure.

Description

technical field [0001] The invention relates to a measuring method in the technical field of optical fiber sensing, in particular to a simultaneous measuring method of bending curvature and bending direction. Background technique [0002] Long period fiber grating (long period fiber grating: LPFG) is a kind of optical fiber passive band-stop filter device that has only appeared in recent years. Long-period fiber gratings have the advantages of no retroreflection, full compatibility with optical fibers, small size, can be embedded in smart materials, and in some respects have better sensing characteristics than fiber Bragg gratings. Therefore, long-period fiber gratings have been widely used in the field of optical fiber sensing since their appearance. The resonant wavelength of LPFG written in ordinary optical fiber by ultraviolet light changes linearly with the increase of bending curvature. Therefore, such LPFGs are better bend sensors. Since the common bending sensitiv...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01B11/24
Inventor 王义平陈建平饶云江
Owner SHANGHAI JIAO TONG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap