Occurrence and removal of wiggles in transient rolling contact simulation

The CONTACT software created by Kalker and further developed by Vollebregt has recently been integrated in dynamical simulation software like RecurDyn and libraries usable in Matlab or C. When such larger packages impose small timesteps compared to the gridsize used, a wiggle-like phenomenon arises. Additionally, transient time-stepping appears to give rise to a smoothing effect that alters detailed traction profiles. A method is presented that focuses on scaling of the timestep for the influence coefficient matrices. This method stops the occurrence of wiggles. Furthermore, the smoothing effect is explained and a solution for this problem is proposed using world-fixed coordinates. These two refinements result in an improved algorithm that allows for small timesteps to be chosen in CONTACT, producing results consistent with results using larger timestep sizes.