A regularized contact model with asymmetric damping and dwell-time dependent friction

A general regularized contact model, including normal compliance, energy dissipation, and tangential friction, is described in this paper. The normal damping coefficient is formulated as a function of the coefficient of restitution e and the impact velocity only; the results are energy-consistent, with continuous force progression at the beginning and end of the impact, for both small and large values of e. The introduced seven parameter friction model based on an explicit formulation of the friction forces is suitable for real-time applications. The friction forces are split into its sliding and sticking contribution and a temporal lag effect, the dwell-time, is included using a novel dwell-time dependent stick state variable. Several examples are presented to demonstrate the features of this general contact model. The simulation results for a double pendulum hitting a plane are obtained, and a comparison with a benchmark problem shows the model behavior is in good agreement with published results.