Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Non-contact measurement method of plane scratch length based on machine vision

A non-contact measurement and machine vision technology, applied in the direction of measuring devices, instruments, optical devices, etc., to achieve the effects of solving measurement errors, improving the scope of application, and high measurement accuracy

Active Publication Date: 2020-09-25
JILIN UNIV
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0009] The purpose of the present invention is to provide a non-contact measurement method of plane scratch length based on machine vision, which overcomes the shortcomings of the existing non-contact measurement and ensures higher detection efficiency and better detection efficiency at lower hardware costs. Detection accuracy

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
  • Non-contact measurement method of plane scratch length based on machine vision
  • Non-contact measurement method of plane scratch length based on machine vision
  • Non-contact measurement method of plane scratch length based on machine vision

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0056] The machine vision-based non-contact measurement method of plane scratch length is to establish a rapid detection method of surface scratch length through image processing technology, and obtain surface scratches through image correction, ROI extraction, threshold segmentation and skeletonization Using the normalized ratio equivalent method to realize the measurement of the surface scratch length of the sub-pixel contour of the, it includes the following steps:

[0057] Step (1), calibrate the camera-CCD industrial camera 4 internal parameters and distortion coefficient. The images of the high-precision calibration plate 6 at different levels are collected by the camera, and the center of the solid circle on the calibration plate 6 is obtained. The camera distortion model is used to obtain the camera internal parameters and the distortion coefficient of the lens 3. The specific process includes the following steps:

[0058] (1.1) Collect 9 images of calibration plate under d...

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 invention relates to a plane scratch length non-contact measuring method based on machine vision and belongs to the field of scratch detection. Firstly, the internal parameters and distortion coefficients of a camera are obtained by means of camera calibration, and three radial distortions and two tangential distortions are introduced into a distortion model; secondly, in order to solve the problem of projection distortion caused by the fact that the optical axis of the camera is not perpendicular to a surface to be measured, according to the method, a calibration result is utilized to establish an image correction model, and a corrected image is obtained; finally, geometric curve characteristics of a scratch to be detected are extracted on the corrected image by means of a subpixel detection algorithm, and the actual length of the scratch is calculated through a normalized proportional coefficient. The method solves the problem that the measured length of the scratch is inaccuratebecause of the relative positions of the camera and the surface to be measured; the requirement for the mounting position of the camera is obviously lowered, and the high measurement precision is ensured.

Description

Technical field [0001] The invention relates to the field of scratch detection, in particular to a non-contact measurement method for the length of a plane scratch based on machine vision. Background technique [0002] With the development of technology, people have higher and higher requirements for product quality and craftsmanship. Surface scratches are one of the most common surface defects. The length and depth of the scratches directly affect the quality of the product. Taking mechanical parts as an example, surface scratches not only affect the appearance of the parts, but also affect the mechanical properties of the parts. Under alternating loads, large scratches are likely to cause stress concentration and fatigue cracks on the parts quickly; scratches will also affect the corrosion resistance of the parts. When scratches appear on the surface of the parts, the corrosion resistance of the parts is obvious Reduce; when scratches appear on the assembly surface between th...

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
Patent Type & Authority Patents(China)
IPC IPC(8): G01B11/30
CPCG01B11/30
Inventor 刘思远张志辉邵天池张云辉于征磊梁云虹
Owner JILIN UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

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

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com