• Acta Photonica Sinica
  • Vol. 49, Issue 7, 712002 (2020)
Li XING1, Hong-zhi ZHANG2, Xi CHEN3、4、*, and Gang WANG5
Author Affiliations
  • 1College of Information, Heilongjiang Agricultural Engineering Vocational College, Harbin 150088, China
  • 2Chang Guang Satellite Technology CO., LTD, Changchun 130102, China
  • 3College of Mechanical and Electrical Engineering, Heilongjiang Institute of Technology, Harbin 150050, China
  • 4College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China
  • 5College of Shipbuilding Engineering, Harbin Engineering University, Harbin 150001, China
  • show less
    DOI: 10.3788/gzxb20204907.0712002 Cite this Article
    Li XING, Hong-zhi ZHANG, Xi CHEN, Gang WANG. Deformation Measurement of Thin-walled Part Based on Binocular Vision[J]. Acta Photonica Sinica, 2020, 49(7): 712002 Copy Citation Text show less

    Abstract

    Aiming at the problem that the deformation measurement of thin-walled part is difficult and complicated, a method of deformation measurement of thin-walled part based on binocular vision is proposed. For the surface deformation of the part, a rigid metal block with reference coordinate system markers is installed on the measured part, and the designed coded targets and color circular markers are pasted on the surface of the part. The effective image region of the reference coordinate system and the coded targets are segmented by the color circular markers, which can eliminate the interferential image features. The identification and detection of coordinate system markers and coded targets are carried out, which realizes the accurate location of centers by using the designed corner structure, and then the 3D coordinates of the measurement points are calculated. The surface deformation of the part is calculated by comparing the changes of the 3D coordinates of the measurement points before and after part deformation. For the edge deformation of part, the improved Canny algorithm is used to extract the edge contour information of part, then the stereo matching and 3D reconstruction are carried out based on epipolar constraint and gray similarity. The experimental results show that the measurement method is reasonable and effective, and the measurement accuracy meets the requirements.
    $ \left\{ \begin{array}{l} {X_C} = {Z_C}({x_L} - c_x^L)/f\\ {Y_C} = {Z_C}({y_L} - c_y^L)/f\\ {Z_C} = Tf/({x_L} - {x_R}) \end{array} \right. $ (1)

    View in Article

    $ {Z_C}\left[ {\begin{array}{*{20}{c}} x\\ y\\ 1 \end{array}} \right] = \left[ {\begin{array}{*{20}{c}} {{f_x}}&0&{{c_y}}&0\\ 0&{{f_y}}&{{c_y}}&0\\ 0&0&1&0 \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {{{\boldsymbol R}_{\rm{D}}}}&{{{\boldsymbol T}_{\rm{D}}}}\\ {{{\boldsymbol o}^{\rm{T}}}}&1 \end{array}} \right]\left[ {\begin{array}{*{20}{c}} {{X_{\rm{W}}}}\\ {{Y_{\rm{W}}}}\\ {{Z_{\rm{W}}}}\\ 1 \end{array}} \right] = {\boldsymbol A}{\boldsymbol M}\left[ {\begin{array}{*{20}{c}} {{X_{\rm{W}}}}\\ {{Y_{\rm{W}}}}\\ {{Z_{\rm{W}}}}\\ 1 \end{array}} \right] $ (2)

    View in Article

    $ \left\{ \begin{array}{l} {{\hat x}_d} - {c_x} = \left( {{x_d} - {c_x}} \right)\left( {1 + {k_1}{r^2} + {k_2}{r^4} + {k_3}{r^6}} \right) + 2{p_1}\left( {{x_d} - {c_x}} \right)\left( {{y_d} - {c_y}} \right) + {p_2}\left( {{r^2} + {2^{\left( {{x_d} - {c_x}} \right)2}}} \right)\\ {{\hat y}_d} - {c_y} = \left( {{y_d} - {c_y}} \right)\left( {1 + {k_1}{r^2} + {k_2}{r^4} + {k_3}{r^6}} \right) + {p_1}\left( {{r^2} + {2^{\left( {{y_d} - {c_y}} \right)2}}} \right) + 2{p_2}\left( {{x_d} - {c_x}} \right)\left( {{y_d} - {c_y}} \right) \end{array} \right. $ (3)

    View in Article

    $ k = 4{\rm{ \mathsf{ ǐ} }}A/{L^2} $ (4)

    View in Article

    $ f\left( {x, y} \right) = {x^2} + Axy + B{y^2} + Cx + Dy = E = 0 $ (5)

    View in Article

    $ F\left( {A, B, C, D, E} \right) = \mathop \sum \limits_{i = 1}^N {f^2}\left( {{x_i}, {y_i}} \right) $ (6)

    View in Article

    $ \frac{{{{\left[ {\left( {x - {x_0}} \right){\rm{cos}}\theta + \left( {y - {y_0}} \right){\rm{sin}}\theta )} \right]}^2}}}{{{a^2}}} + \frac{{{{\left[ { - \left( {x - {x_0}} \right){\rm{sin}}\theta + \left( {y - {y_0}} \right){\rm{cos}}\theta } \right]}^2}}}{{{b^2}}} = 1 $ (7)

    View in Article

    $ \frac{{\partial F}}{{\partial A}} = \frac{{\partial F}}{{\partial B}} = \frac{{\partial F}}{{\partial C}} = \frac{{\partial F}}{{\partial D}} = \frac{{\partial F}}{{\partial E}} = 0 $ (8)

    View in Article

    $ \left\{ {\begin{array}{*{20}{c}} {\tilde x = r\frac{{\left( {\hat x - {x_0}} \right){\rm{cos}}\theta - \left( {\hat y - {y_0}} \right){\rm{sin}}\theta }}{a}}\\ {\tilde y = r\frac{{\left( {\hat x - {x_0}} \right){\rm{sin}}\theta + \left( {\hat y - {y_0}} \right){\rm{cos}}\theta }}{b}} \end{array}} \right. $ (9)

    View in Article

    Li XING, Hong-zhi ZHANG, Xi CHEN, Gang WANG. Deformation Measurement of Thin-walled Part Based on Binocular Vision[J]. Acta Photonica Sinica, 2020, 49(7): 712002
    Download Citation