Perpetual meandering rotation of floating bodies on a supersaturated fluid

1. Free bodies submerged in supersaturated fluids like carbonated water can “dance” vertically, rising and falling periodically due to dynamic surface bubble growth and removal. Body rotation at the fluid‑air interface is critical for destabilizing a weakly stable equilibrium and setting off another plummeting event. In this work, we experimentally investigate the rotational dynamics of 3D‑printed bodies floating atop a basin of carbonated water. Using computer vision, we track body trajectories and reconstruct their rotational velocities, for cylinders and spheres of varying dimensions. We then derive a mathematical model to explain the experimental findings, and to analyze the sensitivity of the dynamics to a number of dimensionless groups. Since most natural bodies exhibit non‑uniform mass distributions, we also fabricate cylinders with controlled center‑of‑mass offsets and extend our model to predict how asymmetric mass distributions alter rotational behaviors. Our observations may provide insights into related fluid mechanical systems, from Quincke rollers to capsizing icebergs.