Robotics engineers at Germany’s Max Planck Institute for Intelligent Systems (MPI-IS) recently took home the Best Paper award at the prestigious Robotics: Science and Systems conference for their work on a jellyfish-inspired microbot. Dubbed “Jellyfishbot,” the little untethered, soft-bodied swimmer boasts both environmental and medical applications.
Dr. Metin Sitti headed up the MPI-IS endeavor. “The idea behind this project was twofold,” Sitti explains. The first iteration of Jellyfishbot was created to study how jellyfish interact with their marine environment.
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Jellyfish are some of the most common and ancient animals in the sea. They play a crucial role in the ocean by mixing it up with their unique “fluidic flow” form of locomotion. By observing the way Jellyfishbot moves, scientists can begin to answer some important questions about the marine ecosystem. “Understanding the relation between the robot’s motion and the incurred fluid flow can help us evaluate possible climate change influences on the water’s mixing,” Sitti says.
But how close is Jellyfishbot to the real thing? The MPI-IS team began by observing ephyra, or baby jellyfish. They watched how they swam, hunted, and stirred up the water around them. They found that the jellyfish used their fluidic flow not only to move but also to trap prey. The researchers then used what they learned to create Jellyfishbot.
The team manipulates the tiny swimmer, which is five millimeters in diameter, using magnetic particles embedded in Jellyfishbot’s elastomer body. The particles provide movement when the team applies an external oscillating magnetic field. This process allows Jellyfishbot to bob around just like its natural counterpart, creating an easily observed analog.
“Obviously, it is much easier to record and measure the swimming of our robot instead of the real thing,” Ziyu Ren, MPI-IS Ph.D. student and co-lead author on the study says. “The swimming motion data is much cleaner, and we can ask questions such as what happens to the fluid around it if the jellyfish swims differently.”
Along with swimming, Jellyfishbot can also “hunt.” In other words, the bot can pick up, carry, and drop “cargo,” as the team calls it. “When we mimic the swimming of the larval jellyfish, we can trap and manipulate objects with this millimeter-sized robot using the same mechanism a jellyfish applies when on the prowl,” Dr. Wenqi Hu, research scientist and co-lead author added. The team published its award-winning paper in the journal Nature Communications.
A follow-up study by Ren and fellow Ph.D. student Tianlu Wang also showcases how Jellyfishbot can help out in the medical field. Scientists are hopeful that the tiny bots could fight cancer by being injected into a patient and using ultrasound imaging to find cancerous tissue.
Then, the bot could release medication in controlled doses. This process would make treatment much less painful for patients, and also, improve medication efficiency.
It looks as if Jellyfishbot has a lot more to do than swim.