Delay Induced Swarm Pattern Bifurcations in Mixed Reality Experiments

Swarms of coupled mobile agents with communication-time delay are known to exhibit multiple dynamic patterns in space, which depend on interaction strength and delay. We demonstrate experimentally delay-induced bifurcations between spatio-temporal patterns with two separate robotic platforms using a mixed-reality framework, and isolate parameter regions where transitions occur. We show that multiple rotation patterns persist in the presence of collision-avoidance and uncertainties in the real robot dynamics. Moreover, we show the existence of multi-stability of rotational patterns not predicted by usual mean field dynamics. Our experimental results increase understanding of swarm-pattern robustness in the physical world, and may form the basis for improved reproducible models of swarms with physical robots.