I have a structure which has a geometric non-linearity due to contact. Let us say that the lengths at t = 0, 0.5, 1 s are 1, 1.5, 1.8 mm respectively.

The final time step in my simulation is 1 second, so when I plot the strains at the final strain, I am assuming that it computes it with respect to its initial configuration (t = 0 s), and the strain will be approximately (1.8 - 1 / 1) = 0.8

Is there a way I can compute strains with respect to an intermediate configuration (e.g., t = 0.5 s), such that the strains will be (1.8 - 1.5 / 1.5) = 0.2? I want to do this because my phenomena of interest happens between 0.5 s-1 s.