  A new scheme for digital image correlation, i.e., short time series DIC
(STS-DIC) is proposed. Instead of processing the original deformed speckle
images individually, STS-DIC combines several adjacent deformed speckle images
from a short time series and then processes the averaged image, for which
deformation continuity over time is introduced. The deformation of several
adjacent images is assumed to be linear in time and a new spatial-temporal
displacement representation method with eight unknowns is presented based on
the subset-based representation method. Then, the model of STS-DIC is created
and a solving scheme is developed based on the Newton-Raphson iteration. The
proposed method is verified for numerical and experimental cases. The results
show that the proposed STS-DIC greatly improves the accuracy of traditional
DIC, both under simple and complicated deformation conditions, while retaining
acceptable actual computational cost.
