The invention is a method to predict the type of deformation of an object
as elastic, plastic or fracture from a time series of specklegram
patterns or fringe patterns (the difference of specklegrams). From the
recorded patterns, a velocity vector field is calculated. The behavior of
the velocity vector, as it evolves in time or space, is used to predict
the deformation type. Fracture is predicted at a particular spatial
location if the velocity vector file shows the dominate wavelength (or
period) as increasing over time at that particular point. Plastic
deformation is predicted at a particular spatial location if the maximum
excursion of the velocity vector field at that particular location is
decaying or distortion tensor parameters begin to depend on locations
(they are different at different locations). Elastic deformation is
predicted at a particular point if the maximum excursion of the velocity
vector filed is approximately constant over time at the particular point
or the distortion tensor parameters are constant (do not vary among
different locations).