3d full-field deformation measuring technique with optics-based measurements

Abstract

Full-field deformation measurements plays a vital role in designing, monitoring and retrofitting many engineering products ranging from civil engineering structure to aerospace applications. Optics-based measurements have gained a vast popularity over last two decades. This paper attempts to establish a method in measuring displacements in a 3D environment, using optics-based measurements, in a cost-effective manner. The study focuses on measuring displacements of a moving object with two stationary cameras. Images acquired from two cameras are processed through MATLAB software package and selected region of the object is reconstructed in a virtual 3D environment at each step. Digital image correlation technique is then adopted to measure displacement by comparing the coordinates of reconstructed objects in each step. It is shown that the displacements can be measured to an accuracy of 0.15 mm (in 20 mm) for the selected object giving an accuracy of 98%.