关键词: 数字图像相关方法, Newton-Raphson迭代, 粒子群优化算法, 初值

Abstract: Since the Digital Image Correlation（DIC） method based on the Newton-Raphson（N-R） method is sensitive to initial values, in the paper, a new DIC method based on the N-R method and the Particle Swarm Optimization（PSO） algorithm is proposed. The new DIC method has the parallel computing capability of the PSO algorithm and local search capability of the N-R method. In searching, the initial values are updated in the process of the alternate iteration of several times by the two methods（N-R and PSO）. The N-R method is used as the last iteration, in which the updated initial values are used. It is found that compared with the N-R method, the new DIC method is not strict to the initial values. This is due to the fact that the initial values of the displacement and strain have been updated since the two methods iterate alternately several times. The displacement and strain of points on a surface of a simulated material model stressed are calculated during the failure and satisfying results are obtained.

Key words: digital image correlation method, Newton-Raphson iteration method, particle swarm optimization algorithm, initial value