Hello, my name is Amelia and I love robots. I love robots in all shapes and sizes. As the host of Amelia’s Weekly Fish Fry podcast at EEJournal.com, I have had the privilege to report on the advancements and innovations in robotics quite a bit over the last ten years and two of my all-time favorite stories involve very small robots.
Tiny, sea-creature-inspired robots
Have you heard of the tiny, octopus shaped robots developed by Northwestern University? Inspired by sea creatures and made to be used in aquatic environments, these centimeter-sized robots are shaped like four legged octopi and are made of up of around ninety percent water by weight. These tiny aquatic robots can walk at human speed, climb hills, transport cargo, and do a funny little break-dance motion to release a particle as well. And they do all of this without complex hardware, electricity or hydraulics. How? They are activated by light and walk in the direction of an external rotating magnetic field.
These sea-creature-inspired robots are constructed of a soft matter that includes a hydrogel that contains a scaffold-like structure made up of ferromagnetic nanowires that change shape in response to light. So, when these robots encounter light, the molecules in the hydrogel become hydrophobic. When this hydrophobic process occurs, the robots repel water which causes the robot to change from the flat position to a standing position. When the light is turned off, the robot will return to its flat position because its water molecules have gone back to their original state.
These robots also respond very quickly to rotating magnetic fields. When they are in a bent position and a rotating magnetic field gets close to them, their embedded skeleton exerts cyclic forces to activate their legs. When the magnetic fields rotate fast enough, these tiny robots have the ability to walk as fast as a human.
When the team from Northwestern University combined these steering motions and walking motions together, they were able to remotely operate and direct the robots through narrow passages and complex routes.
Once the robots’ responses to magnetic fields and light were coupled, the researchers managed to make the robots pick up cargo and deliver it to a specific destination by rolling or walking. To drop cargo off at its destination, the robot can either invert its shape, thereby allowing the cargo to just slide off, or it can perform a breakdance spin-type motion to dislodge the cargo.
Samuel Stupp, head researcher on this project at Northwestern University, puts his research in perspective like this, saying: “Conventional robots are typically heavy machines with lots of hardware and electronics that are unable to interact safely with soft structures, including humans. We have designed soft materials with molecular intelligence to enable them to behave like robots of any size and perform useful functions in tiny spaces, underwater or underground.”
Seeing a bright future for future applications, Samuel says: “Eventually, we’d like to make armies of microrobots that could perform a complicated task in a coordinated way. We can tweak them molecularly to interact with one another to imitate the swarming of birds and bacteria in nature or schools of fish in the ocean. The molecular versatility of the platform could lead to applications that have not been conceived at this point.”
The world’s first self-replicating living robots
Did you hear that a team of researchers created the world’s first millimeter-sized living, programmable organisms? With the help of some programmed repurposed living cells scraped from frog embryos, along with a specialized algorithm that created thousands of simulated designs for new life-forms, a team of researchers from the University of Vermont, Tufts University, and the Wyss Institute for Biologically Inspired Engineering at Harvard University created a new class of artifact called Xenobots. A mere eleven months later, this team was able to design these Xenobots to replicate themselves, thereby discovering an entirely new form of biological reproduction.
So, how does this new form of reproduction apply to these new millimeter-sized living, programmable organisms? The team found that their Pac-Man shaped Xenobots could swim out into their petri dish, find single cells, gather hundreds of them together, and then assemble these “baby” Xenobots inside their mouths. And then, BAM! A few days later, there were new Xenobots that look and move just like their “parents.”
An important key in this new discovery within Xenobot replication is the use of an artificial intelligence (AI) program that uses the Deep Green supercomputer cluster at UVM’s Vermont Advanced Computing Core. This algorithm was able to test billions of body shapes in simulation—pyramids, triangles, starfish, squares—with the goal to find a body shape for the parent Xenobots that would be the most effective at motion-based kinematic replication, Eventually, it came up with the shape of Pac-Man, and it worked.
This kind of kinematic replication is not new—it’s a well-known method to reproduce molecules—but, until now, it had not been observed at this scale.
Michael Levin, Ph.D., a professor of biology and director of the Allen Discovery Center at Tufts University and co-leader of the new research, puts it in focus like this: “This is profound. These cells have the genome of a frog but, freed from becoming tadpoles, they use their collective intelligence, a plasticity, to do something astounding.”
So, where are we going with this research? Joshua Bongard, Ph.D, a computer scientist and robotics expert at the University of Vermont who co-led the new research contends that this type of research goes beyond building Xenobots in petri dishes. As he says: “The speed at which we can produce solutions matters deeply. If we can develop technologies, learning from Xenobots, where we can quickly tell the AI: ‘We need a biological tool that does X and Y and suppresses Z,’ that could be very beneficial. We need to create technological solutions that grow at the same rate as the challenges we face.”
Would you like to listen to more stories about robotics? To celebrate the five hundredth episode of my EE Journal Fish Fry podcast, we launched a special playlist that highlighted nine different podcast episodes that feature stories about robotics. These include my interview with Florian Pestoni, CEO of InOrbit, about the future of AI and robotics in the workforce, and also my discussion with HanBin Lee, CEO of Seoul Robotics. You can check out these episodes on youtube.com/eejournal or by visiting eejournal.com and selecting the “Fish Fry” header at the top.