Experimental Modeling of Chiral Active Robots and a Minimal Model of Non-Gaussian Displacements

TL;DR

This paper experimentally investigates chiral active particles, modeling their dynamics with overdamped chiral active Brownian particles, and introduces a minimal model explaining non-Gaussian displacement phenomena observed in these systems.

Contribution

It presents a minimal model that captures non-Gaussian displacement distributions and the transition from single to double peaks, advancing understanding of active particle dynamics.

Findings

Experimental particles follow chiral active Brownian motion

Minimal model reproduces double-peak velocity distributions

Transition from single to double-peak displacement observed

Abstract

We design 3D-printed motor-driven active particles and find that their dynamics can be characterized using the model of overdamped chiral active Brownian particles (ABPs), as demonstrated by measured angular statistics and translational mean squared displacements (MSDs). Furthermore, we propose a minimal model that reproduces the double-peak velocity distributions and further predicts a transition from the single-peak to the double-peak displacement distributions in short-time regimes. The model provides a clear physics picture of these phenomena, originating from the competition between the active motion and the translational diffusion. Our experiments confirm such picture. The minimal model enhances our understanding of activity-driven non-Gaussian phenomena. The designed particles could be further applied in the study of collective chiral motions.