For Its Size, This ‘Ultrafast’ Small-Scale Soft Robot Is Faster than ‘Most Animals’

A team of researchers at Johannes Kepler University in Austria has created small-scale “ultrafast” robots that are driven via electromagnetic fields, can carry “cargo,” and are faster than “most animals.”

Small-scale robots—which can range in size from the millimeter scale to the nanoscale—continue to develop more and more degrees of freedom. And cargo delivery methods. One new small-scale “ultrafast” bot developed by researchers at Johannes Kepler University in Austria adds a helping of speed to the mix. In fact, for its size, the bendy bipedal-ish robot is faster than “most animals.”

“High-speed locomotion is an essential survival strategy for animals, allowing [the inhabitation of] harsh and unpredictable environments,” the researchers write in a study published in Nature Communications outlining their ultrafast robots. “Bio-inspired soft robots equally benefit from versatile and ultrafast motion but require appropriate driving mechanisms and device designs,” they add.

To that end, the researchers, including Guoyong Mao, et al. created a class of “curved” small-scale robots controlled by electromagnetic fields acting upon printed liquid metal channels embedded in their soft, elastic “bodies.” More specifically, the electromagnetic fields modulated the Lorentz forces—or the forces that act upon charged particles due to electric and magnetic fields—applied to the embedded printed liquid metal channels, which themselves carried alternating currents.

Image: Guoyong Mao et al, Ultrafast small-scale soft electromagnetic robots, Nature Communications (2022)

To generate the alternating currents (and thusly the ability to move), the robots were connected to an external source of power via electrodes. In the video immediately above note the wire tether connected to the electrodes, which are attached to the top of the robot. 

The results, as the video (assembled by Tech Xplore) shows, is a small-scale robot that’s able to move at “an ultrafast relative speed” of 70 body lengths per second (BL/s). This measurement, the researchers note, quantifies the velocity of different organisms across a large spectrum of body sizes. And can be as high as 323 BL/s for the mite Paratarsotomus macropalpis.

Image: Guoyong Mao et al, Ultrafast small-scale soft electromagnetic robots, Nature Communications (2022)

For reference, Tech Xplore notes in its report on the small-scale ultrafast bots that a cheetah runs at speeds of somewhere between 20 and 30 BL/s. In fact, the researchers note in their study that their “Vibrating SEMRs [or small-scale soft electromagnetic robots] exhibit dynamics similar to a running cheetah, which inspired the development of the ultra-fast running robot.”

The small-scale curved robots aren’t only just fast—17.5 times faster than previous soft-bodied robots, in fact—but also capable of jumping, swimming, “navigating” their terrain, and, of course, delivering cargo. Indeed, the small-scale class of robot is evidently quite modular, allowing for different builds for different purposes. In the image immediately above we see an untethered version with L-shaped feet (SEMR UL); an untethered version with rectangular feet (SEMR UR1); and an untethered version with rectangular feet (UR2). (The different feet help the robots to grip different types of surfaces.)

As for potential uses, the researchers say these small-scale ultrafast robots generally help to develop “human-robot interaction,” as the interface between robots and the biological organism requires “soft, safe, fast and robust [robot] designs capable of operation in harsh, dynamic environments.” For an example of one of these harsh and dynamic environments, Mao et al. offer the human stomach. Specifically, they say small-scale bots like these could work to treat gastrointestinal tract-related diseases via drug delivery or “non-invasive surgery.” Because what sounds more trustworthy than tiny robots swimming around in your stomach trying to make incisions?

Feature image: Guoyong Mao et al, Ultrafast small-scale soft electromagnetic robots, Nature Communications (2022) via Tech Xplore

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