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

A method for segmenting point cloud data of a shield tunnel surface

A technology of shield tunneling and surface points, applied in image data processing, 3D image processing, instruments, etc., to simplify calculations and improve fitting accuracy

Active Publication Date: 2019-03-08
NANJING FORESTRY UNIV
View PDF3 Cites 8 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] The present invention proposes a method for segmenting point cloud data on the surface of a shield tunnel. Segment method provides technical support for subsequent tunnel modeling and deformation analysis based on point cloud

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
  • A method for segmenting point cloud data of a shield tunnel surface
  • A method for segmenting point cloud data of a shield tunnel surface
  • A method for segmenting point cloud data of a shield tunnel surface

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0022] A method for segmenting surface point cloud data of a shield tunnel, comprising the following steps:

[0023] (1) Shield tunnel point cloud projection: According to the overall direction of the shield tunnel point cloud, select XOY, YOZ, or XOZ Two of the surfaces are used as projection surfaces to convert the 3D point cloud into 2D and simplify the calculation;

[0024] (2) Boundary point extraction: Grid the projected two-dimensional point cloud in the plane, and use the grid to extract the upper and lower boundary points of the point cloud;

[0025] (3) Calculation of tunnel point cloud segmentation position:

[0026] a) Calculation of the tangent slope of the extracted boundary points: fit the boundary neighborhood of the shield tunnel point cloud, and calculate the slope by deriving the fitting function;

[0027] b) Segmented position calculation: establish a K-X coordinate system with the tangent slope as the vertical axis, and perform fitting analysis on the ta...

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

A method for segmenting point cloud data of a shield tunnel surface includes such step of projecting the point cloud of a shield tunnel, and converting three-dimensional point cloud to two-dimensionalpoint cloud according to the direction of the point cloud of shield tunnel; 2) extracting the boundary point, gridding the projected two-dimensional point cloud, and extracting the upper and lower boundary points of the point cloud by using the grid; 3) calculating the segmentation position of the tunnel point cloud, comprising a) calculation of tangent slope of extracted boundary point; and (b)subparagraph position calculation; 4) processing that segment positions of the shield tunnel point cloud on the two projection plane jointly to complete the segmentation of the whole tunnel point cloud data, so as to prepare for the modeling of the tunnel point cloud. The present invention has the advantages that 1) the segmentation method of point cloud on the surface of shield tunnels is studied, which provides technical support for the extraction of the central axis of shield tunnels based on TLS technology, section analysis and other point cloud processing methods. 2) the method can effectively improve the accuracy of the axis fitting and supplement the deformation monitoring technology of shield tunnels, and has the important practical value in the safety monitoring of shield tunnelsand the prevention of major accidents.

Description

technical field [0001] The invention relates to a method for segmenting surface point cloud data of a shield tunnel, belonging to the technical field of civil engineering safety monitoring. Background technique [0002] The shield tunnel deformation monitoring technology based on Terrestrial Laser Scanning (TLS) is a hot technology in the field of deformation monitoring. The current TLS-based deformation monitoring method of the shield subway tunnel is to obtain the tunnel section by extracting the central axis, analyze the tunnel section, and obtain the tunnel deformation value. Some studies extract the points on the central axis of the tunnel and directly perform quadratic curve fitting to obtain the central axis. However, for tunnels with straight and curved segments, directly using quadratic curve fitting reduces the accuracy of central axis extraction. . If the tunnel can be accurately segmented, then extracting the central axis of the segmented tunnels will improve t...

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 Applications(China)
IPC IPC(8): G06T15/00G06T3/00
CPCG06T15/00G06T3/06Y02T90/00
Inventor 史玉峰曹震曹伟陈动
Owner NANJING FORESTRY 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