Dynamics of capillary self-alignment for mesoscopic foil devices

We report experimental evidence for three sequential, distinct dynamic regimes in the capillary self-alignment of centimeter-sized foil dies released at large uniaxial offsets from equilibrium. We show that the initial transient wetting regime, along with inertia and wetting properties of the dies, significantly affect the alignment dynamics including the subsequent constant acceleration and damped oscillatory regimes. An analytical force model is proposed that accounts for die wetting and matches quasi-static numerical simulations. Discrepancies with experimental data point to the need for a comprehensive dynamical model to capture the full system dynamics. (C) 2013 American Institute of Physics.