Application of radial basis functions in strain analysis of digital image correlation

Digital image correlation systems provide the motion of material points on surface a specimen or component. Commonly, local interpolation concepts are chosen to determine in-plane strains principal stretches. However, this approach yields discontinuous fields. In paper, global concept, particular, radial basis functions is considered displacement and strain field overcome underlying problem discontinuities. Since there might be boundary effects, i.e. larger errors in approximation comparison analytical verification examples, multiquadric applied as particular function. It turns out that error becomes smaller at edges domain interest, although condition number resulting equations scheme, critical. studies additively manufactured parts lead conclusion promising for real-world applications.