• Optics and Precision Engineering
  • Vol. 31, Issue 3, 380 (2023)
Chuanfu SUN1, Tao PENG1, Yonggang LU2, Kun XU2, and Zhijiang ZHANG1,*
Author Affiliations
  • 1Key Laboratory of Specialty Fiber Optics and Optical Access Networks, Shanghai University, Shanghai200444, China
  • 2Metallurgical Baosteel Technology Service Co. LTD., Shanghai01999, China
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    DOI: 10.37188/OPE.20233103.0380 Cite this Article
    Chuanfu SUN, Tao PENG, Yonggang LU, Kun XU, Zhijiang ZHANG. Fast extraction center stripe of multi-line-structured light for three-dimensional measurement of casting slab[J]. Optics and Precision Engineering, 2023, 31(3): 380 Copy Citation Text show less
    Gray-scale statistics of laser stripe cross-section
    Fig. 1. Gray-scale statistics of laser stripe cross-section
    Images of casting slab
    Fig. 2. Images of casting slab
    Gray scale surfaces of casting slab
    Fig. 3. Gray scale surfaces of casting slab
    Image processed by background difference method
    Fig. 4. Image processed by background difference method
    Gray value curves at line 2560th row
    Fig. 5. Gray value curves at line 2560th row
    Optimization principle of gray-gravity method
    Fig. 6. Optimization principle of gray-gravity method
    Scene of three-dimensional measurement system for casting slab
    Fig. 7. Scene of three-dimensional measurement system for casting slab
    Image of ROI extraction fragment of line-structured light
    Fig. 8. Image of ROI extraction fragment of line-structured light
    Adaptive gray threshold
    Fig. 9. Adaptive gray threshold
    Comparison of extraction errors of different stripe center extraction methods
    Fig. 10. Comparison of extraction errors of different stripe center extraction methods
    Extraction results of different laser lines with different brightnesses
    Fig. 11. Extraction results of different laser lines with different brightnesses
    Line-structured light on surface of casting slab and its three-dimensional reconstruction
    Fig. 12. Line-structured light on surface of casting slab and its three-dimensional reconstruction
    MethodMean pixel valueStandard deviation
    Steger Method1160.3340.123
    Extreme value660.2350.970
    GGM960.3410.365
    Proposed method60.3450.112
    Geometric center1660.0000.707
    Table 1. Extraction errors of different strip center extraction methods
    No.GGM9

    Steger

    method11

    Proposed method
    11035 136346
    2955 139292
    3895 157284
    41125 655318
    51005 136288
    6995 211288
    71005 080286
    Table 2. Running time of light bar center point extraction
    No.Upper edge pointsLower edge points
    xyzxyz
    1-491.200238.831 619.94-543.88251.271 618.43
    2-495.130575.361 633.69-542.01582.071 634.33
    3-496.750747.651 636.70-540.40766.511 637.59
    4-497.510966.8471 641.35-538.40978.241 641.18
    5-498.7301 213.171 647.47-536.991 225.991 646.80
    6-498.6861 480.001 654.00-533.461 454.731 651.55
    7-500.9401 717.111 659.15-532.021 716.721 657.85
    8-500.9091 880.561 661.92-530.421 878.531 660.78
    Standard deviation1.521.73
    Table 3. Three dimensional measurement results of upper and lower edge points of casting slab
    Chuanfu SUN, Tao PENG, Yonggang LU, Kun XU, Zhijiang ZHANG. Fast extraction center stripe of multi-line-structured light for three-dimensional measurement of casting slab[J]. Optics and Precision Engineering, 2023, 31(3): 380
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