Patterns, transitions and the role of leaders in the collective dynamics of a simple robotic flock

TL;DR

This study investigates how simple robotic flocks exhibit collective motion driven by collisions, noise, and leadership, demonstrating that small groups of leaders can steer the entire flock and that noise influences the transition between different collective states.

Contribution

It introduces a simple experimental setup with self-propelled robots to study collective dynamics, highlighting the role of leaders and noise in pattern formation, supported by agent-based simulations.

Findings

Leaders can effectively control flock direction with minimal members.

Noise facilitates faster and more robust ordering.

Jamming reduces the correlation between density and ordered motion.

Abstract

We have developed an experimental setup of very simple self-propelled robots to observe collective motion emerging as a result of inelastic collisions only. A circular pool and commercial RC boats were the basis of our first setup, where we demonstrated that jamming, clustering, disordered and ordered motion are all present in such a simple experiment and showed that the noise level has a fundamental role in the generation of collective dynamics. Critical noise ranges and the transition characteristics between the different collective patterns were also examined. In our second experiment we used a real-time tracking system and a few steerable model boats to introduce intelligent leaders into the flock. We demonstrated that even a very small portion of guiding members can determine group direction and enhance ordering through inelastic collisions. We also showed that noise can facilitate and speed up ordering with leaders. Our work was extended with an agent-based simulation model, too, and high similarity between real and simulation results were observed. The simulation results show clear statistical evidence of three states and negative correlation between density and ordered motion due to the onset of jamming. Our experiments confirm the different theoretical studies and simulation results in the literature about collision-based, noise-dependent and leader-driven self-propelled particle systems.