Reinforcement learning of a biflagellate model microswimmer

Sridhar Bulusu; Andreas Zöttl

doi:10.1140/epje/s10189-025-00513-3

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arXiv · 2508.15561

Reinforcement learning of a biflagellate model microswimmer

Sridhar Bulusu·Andreas Zöttl

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Abstract

Many microswimmers are able to swim through viscous fluids by employing periodic non-reciprocal deformations of their appendages. Here we use a simple microswimmer model inspired by swimming biflagellates which consists of a spherical cell body and two small spherical beads representing the motion of the two flagella. Using reinforcement learning we identify for different microswimmer morphologies quasi-optimized swimming strokes. For all studied cases the identified strokes result in symmetric and quasi-synchronized beating of the two flagella beads. Interestingly, the stroke-averaged flow fields are of pusher type, and the observed swimming gaits outperform previously used biflagellate microswimmer models relying on predefined circular flagella bead motion.

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Sridhar Bulusu, Andreas Zöttl. 2025-08-21. Reinforcement learning of a biflagellate model microswimmer. https://doi.org/10.1140/epje%2Fs10189-025-00513-3

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