This paper describes the use of the digital image correlation (DIC) method of deformation measurement suited to finite element method modelling. The technique has applications in component manufacture in the automotive industry. Displacement of the tested material is inferred by tracking the deformation of a random speckle pattern, applied to a component's surface, in digital images acquired during load testing. More recently, the DIC method has been extended to use multiple cameras, permitting measurement of three-dimensional shape and deformation. One particular DIC algorithm is preferred for deformation analysis because it can measure arbitrarily large rotations and strains and performs with superior accuracy and efficiency. It is based on an iterative solution process for finding the maximum of the cross-correlation coefficient in an n-dimensional parameter space. DIC has an advantage when locally varying material properties are being measured, as the modulus and yield strength can be measured in a single tension test. Examples of use are given. For the covering abstract see ITRD E126782.
Samenvatting