Affiliation:
1. Dalian University of Technology
Abstract
As a noncontact optical measurement method, the digital image correlation (DIC) method
can provide full-field displacement and strain measurement during
object deformation. In the case of small rotation deformation, the
traditional DIC method can obtain accurate deformation measurement
results. However, when the object rotates at a large angle, the
traditional DIC method cannot obtain the extreme value of the
correlation function, resulting in the occurrence of decorrelation. In
order to address the issue, a full-field deformation measurement DIC
method based on improved grid-based motion statistics is proposed for
large rotation angles. First, the speeded up robust features algorithm
is applied to extract and match the feature point pairs between the
reference image and the deformed image. Furthermore, an improved
grid-based motion statistics algorithm is proposed to eliminate the
wrong matching point pairs. Then, the deformation parameters of the
feature point pairs obtained by the affine transformation are taken as
the initial deformation value for DIC calculation. Finally, the
intelligent gray-wolf optimization algorithm is used to obtain the
accurate displacement field. The effectiveness of the proposed method
is proved by simulation and practical experiments, and the comparative
experiments show that the proposed method is faster and more
robust.
Funder
National Natural Science Foundation of China
Subject
Computer Vision and Pattern Recognition,Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials