Inducing rotational motion in the mercury beating heart system

In this paper, we report experimental results showing the generation of rotational motion in a non-autonomous Mercury Beating Heart system. Using an electrochemical cell under potentiostatic conditions, a traveling chemomechanical wave can be created on the periphery of the surface of a mercury drop, placed on a concave glass surface, and completely immersed in an acidic media. Due to the spherical geometry of the container, this chemomechanical wave deforms continuously the surface of the drop to induce a variety of rotatory dynamics with different topological structures. In the present study, the applied potential was systematically varied to observe the different dynamical structures. Since the time series of the generated current does not provide useful information, the corresponding image analysis of the bidimensional projection of the surface of the drop was performed in order to verify the existence of the traveling waves.