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arXiv · 2606.15028

An Autonomous Subgram SMA-Based Swimmer

Conor K. Trygstad·Francisco M. F. R. Gonçalves·Néstor O. Pérez-Arancibia
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Abstract

We present the Swima, a bioinspired 900-mg swimmer propelled by two 10-mg high-work-density (HWD) actuators driven by shape-memory alloy (SMA) wires. We integrated onboard power and computation by using a custom-built printed circuit board (PCB) and an 11-mAh 3.7-V 507-mg single-cell lithium-ion (Li-Ion) battery, which in conjunction enable autonomous swimming in excess of 18 min. The Swima can swim at speeds of up to 22.4 mm/s (0.56 Bl/s), achieves turning rates of up to 14{\deg}/s, and can follow 0-degree heading reference trajectories with root mean square (RMS) values of tracking errors of about 6.5{\deg} across multiple tests. This robot is the first subgram microswimmer with onboard power, actuation, and computation developed to date.

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Conor K. Trygstad, Francisco M. F. R. Gonçalves, Néstor O. Pérez-Arancibia. 2026-06-12. An Autonomous Subgram SMA-Based Swimmer. https://arxiv.org/abs/2606.15028

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