Indexed by:会议论文

Date of Publication:2014-08-22

Included Journals:EI、CPCI-S、Scopus

Volume:9233

Key Words:digital gradient sensing (DGS); elasto-optic constant; image processing; least-squares method

Abstract:The digital gradient sensing (DGS) method is a full-field optical technique to measure the in-plane stress gradients of transparent materials. Elasto-optic constant is an important material characteristic for the DGS method and is usually not given. On the basis of introducing the working principle of DGS method, a calibration method of elasto-optic constant based on the least-squares method is proposed, and the accuracy of iterative convergence is improved by introducing liner error. A theoretical model of a semi-infinite plane under concentrated normal load on boundary is chosen to verify the feasibility of the proposed method. The full-field experimental data of polymethyl methacrylate specimen is obtained from the digital image correlation method. The experimental results show that the least-squares calibration method can determine the elasto-optic constant of transparent materials effectively.