This squirming robotic superstructure is the next Roomba

What do a mighty morphing dinosaur, several children in a trench coat, and a swarm of smiling robots have in common? They know there’s power in numbers — at least when it comes to their constituent parts.

Megazord from the Power Rangers franchise and the Teselecta from Doctor Who are examples of superstructures, or a structure in robotics made up of tinier robots. And they’re not just science fiction anymore.

In a new paper published Wednesday in the journal Science Robotics, a team of physicists from the University of Bordeaux designed a new kind of superstructure that uses mindless mini-robots to power a seemingly intelligent superstructure that can squeeze through obstacles, pull things, and even battle other superstructure bots.

“We made them play games — we played billiards — and they do it so well that you're like, ‘The hell with it, they are intelligent!’” Hamid Kellay, a professor of physics at the University of Bordeaux and a senior author on the paper, tells Inverse. “But they’re not.”

What’s new — When it comes to the mini-robots themselves, which Kellay calls “bugs,” he says they’re not too different from what you find in similar studies on this subject. And in fact, they’re the same kind of small, vibrating toy you might give a child or a cat. They’re roughly 1.7 inches long and less than an inch tall and colored orange and red with tiny, non-functional legs.

Using these off-the-shelf toys helps the lab cut down on time and money in 3D printing something of their own, Kellay explains.

The true significance of their studies lies in the collaborative motion they observed when a collection of the robot bugs were set loose in a thin, flexible shell — similar to putting a wind-up toy inside a rubber band. Even though these bugs are truly mindless (i.e., they’re just a plastic shell and a vibrating motor), they appear to move intelligently within the flexible scaffold.

Studying how these superstructures move through different obstacles will help the research team understand the new kinds of forces these superstructures exert, says Kellay. In other words, how they interact with the world around them.

Why it matters — These kinds of superstructures are still in the early stages of development. Still, Kellay says they could have several practical applications in the future, including cleaning hard-to-reach or dangerously infected areas of your house.

And if they were to be scaled down much smaller in the future, these bots might one day also play an important role in the future of internal drug delivery.

How it works — Unlike complex speaking or dancing robots that might seem standard today, Kellay says that these robots and driven purely by “physics and chance.”

Here’s how they work in a nutshell:

• The robot bugs are painted with small lines to help the researchers keep track of their orientation
• These bugs are then let loose in a flexible scaffold on a flat surface
• Turned on, these bugs vibrate and move randomly until they run into one another
• Running into each other then creates a “clustering” movement where the bugs align together at a barrier
• This collaborative movement at the barrier then propels the entire scaffold, or superstructure, forward

The team put these superstructures through many trials, including climbing through small openings, cleaning up obstacles, and even battling each other for supremacy.

In later trials, the team also outfitted a group of the bugs with what Kellay describes as a tiny backpack containing an extra motor, light sensor, and battery. When exposing this group of bugs to bright light, the researchers found they would change their motion from a straight line to a small orbit.

“If you have no lights, they will go straight, but if you turn the light on and turn the second motor on, they start orbiting,” explains Kellay. “This orbiting actually turns out to be very nice because when you put a bunch of these things into this scaffold when they're turning like this, they generate more collisions... and cluster faster.”

This means you need fewer bugs to accomplish the same result.

What’s next — In the future, Kellay says he’s interested in exploring more options for controlling these structures using flashing lights to maneuver individual bots at a time.

And as a professor, Kellay says he’s also excited for the learning opportunity these “idiotic” little bugs offer for students just getting interested in the field of physics.

“Things like this are of really of high educational value,” says Kellay. “Show this to kids, and you get them immediately interested... As a university professor, that’s very important to me.”

Abstract: A swarm of simple active particles confined in a flexible scaffold is a promising system to make mobile and deformable superstructures. These soft structures can perform tasks that are difficult to carry out for monolithic robots because they can infiltrate narrow spaces, smaller than their size, and move around obstacles. To achieve such tasks, the origin of the forces the superstructures develop, how they can be guided, and the effects of external environment, especially geometry and the presence of obstacles, need to be understood. Here, we report measurements of the forces developed by such superstructures, enclosing a number of mindless active rod-like robots, as well as the forces exerted by these structures to achieve a simple function, crossing a constriction. We relate these forces to the self-organization of the individual entities. Furthermore, and based on a physical understanding of what controls the mobility of these superstructures and the role of geometry in such a process, we devise a simple strategy where the environment can be designed to bias the mobility of the superstructure, giving rise to directional motion. Simple tasks—such as pulling a load, moving through an obstacle course, or cleaning up an arena—are demonstrated. Rudimentary control of the superstructures using light is also proposed. The results are of relevance to the making of robust flexible superstructures with nontrivial space exploration properties out of a swarm of simpler and cheaper robots.