We investigated the effects of interstitial air on the impact bifurcations of period doubling motion in vertically vibrated grains beds. The impact of grains on the container bottom undergoes a series of subharmonic bifurcations as the vibration intensity increases. With the presence of air, the...

We investigate the dynamics of a plastic ball on a vibrated platform in air by introducing air damping effect into the completely inelastic bouncing ball model. The air damping gives rise to larger saddle-node bifurcation points and a chaos confirmed by the largest Lyapunov exponent of a...