Digital Image Correlation of Two-Dimensional Trajectory and Deformation Measurement and Applied to Construct 3D Surface

Autor: Sheng-Yi Wang, 王盛儀
Rok vydání: 2018
Druh dokumentu: 學位論文 ; thesis
Popis: 106
This thesis start from verifying 2D Digital Image Correlation (DIC) ability then expand the topic to 3D measuring errors, and finally build a 3D surface constructing system by using single camera and automatic devices. 2D DIC trajectory measurement ability can be proven by comparing to 1D LASER displacement meter result, and have successfully matched by measuring XXY precision stage origin motion trajectory and displacement. The stage operating system had defect of overshooting, and have been fixed by applying a protecting logic circuit which will block the motor input for state of limit. Also, the system is changed into MATLAB environment for compatibility and has improved the degree of freedoms for angle displacement, direction and speed. The stage is found having better trajectory result compared with the shape of input command while operating with lower speed. Measurement of a three-point-forced acrylic circular plate is used to verify the full-field displacement and deformation ability of 2D DIC. The result of displacement and deformation measured by 2D DIC system are similar to the displacement and deformation simulations computed by COMSOL. This thesis presents a relationship between 2D and 3D measurement error derived by geometry, and gives a procedure to make sub-pixel standard image which verifies the 2D DIC method with an accuracy of 0.02 pixel. 3D measurement error can be predict by applying coordinate values of point in 3D space and error on 2D plane and verified by a test measuring feature point in different positions. At last, the thesis build a 3D surface measuring system by single camera, a single axis robot and precision stage, which have the possibility to capture photos for different view angle. The system ability is verified from measuring checker board plane, and successfully built 3D surface of an unequal diameter PVC pipe and a Beethoven plaster statue.
Databáze: Networked Digital Library of Theses & Dissertations
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