The traditional theory about the digital-image correlation method (DICM) is modified, and a nonlinear displacement model is proposed and developed. On the basis of the displacement mode, both the Jacobian Vector and the Hessian matrix of the Newton- Raphson iterative method for estimating the approximate values of displacements and their gradients are given. The computer software for the nonlinear DICM is developed. In this paper, a rubber specimen stretched is employed, and the strain components at an arbitrary point of interest are computed using the nonlinear DICM. The experimental results show that the research work lays foundations for improving the accuracy of measuring finite deformation using DICM.

Date Published: 29 May 2002
PDF: 4 pages
Proc. SPIE 4537, Third International Conference on Experimental Mechanics, (29 May 2002); doi: 10.1117/12.468873

Published in SPIE Proceedings Vol. 4537:
Third International Conference on Experimental Mechanics
Xiaoping Wu; Yuwen Qin; Jing Fang; Jingtang Ke, Editor(s)