Error Analysis of Displacement Measurements Based on Digital Image Correlation Method

The error of displacement measurements by digital image correlation method is examined from a pratical perspective. Different from previous research, this study focuses on external factors influencing the accuracy of displacement measurement in the study of cooperative mark recognition and camera placement. Our major objectives of this research include indentificating the chief error sources and assessing their influences on the testing results. There are 5 parts in this paper. We start with a brief introduction of the necessity of analyzing the errors. After reviewing the principles of digital image correlation method, an detailed discussion of error soureces of this method is provided. Then we design a pratical experiment measuring the characteristics of a spring vibrator using the digital image correlation mesurement systems and laser displacement sensor. By comparing the results from two ways of measurment, we end the study with the conclusion that the accuracy of displacement measuring by digital image correlation method is tightly related to the choice of cooperative mark and camera intersection angle.