Guobiao Yang

Single Camera 3D Digital Image Correlation Using a Polarized System

In this paper, a novel single camera three dimensional digital image correlation (3D-DIC) system, using a polarized pseudo-stereo system, is proposed. Compared to traditional 3D-DIC systems using stereovision, it has a more compact structure and better vibration resistance. Compared to the conventional single camera pseudo-stereo system that splits the CCD sensor into two halves to capture the stereo views, the proposed system achieves both views using the entire CCD chip without reduction of the spatial resolution. In addition, the center of the two views stands in the center of the CCD chip, similarly to conventional 3D-DIC systems, thus minimizing the image distortion compared to the conventional pseudo-stereo system. The two overlapped views in the CCD sensor are separated using the different polarization states, and the standard 3D-DIC algorithm can be utilized directly to perform the evaluation. The principal and experimental setup are described in detail, and multiple tests are performed to validate the system.

Forming Limit Diagram Determination Using Digital Image Correlation: A Review

The forming limit diagram (FLD) is one of the most important criteria in sheet metal forming because the formability of materials can be assessed by the FLD. Recently, different measurement methods based on Digital Image Correlation (DIC) have been developed for FLD. This paper presents a review of DIC for FLD determination, the principle of each method is descripted, and the pros and cons of these methods are discussed.