从云纹数字图象直接建立应变场图象的新方法

A NEW METHOD FOR CONSTRUCTING DIGITAL-STRAIN -FIELD-IMAGE FROM MOIRE PATTERN

本文提出一种从云纹数字图象直接建立数字应变场图象的新方法。数字应变场图象直接用图象灰度表示应变大小。此方法不但得到定量的、直观形象的应变场图象,且方法简单,实用,满足工程精度要求。

A new method for constructing digital-strain-field-image from a moire pattern with the help of digital image processing technique is proposed in this paper. The digital-strain-field-image expresses the train values directly by its grey levels. The digital moire image is pre-processed by the separate linear enhancing transformation.Then the digital-strain-field-image can be obtained by making a differentiation for the digital moire pattern and doing a simple division operation. The digital-strain-field-image not Only gives the visual strain-field distribution, but also gives the strain values of every point.This method is simple and applicable and has satisfactory accuracy.