An Autonomous Subgram SMA-Based Swimmer (opens in new tab)

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), achi...