“It’s kind of like a Swiss army knife for robot tasks,” says Daniela Rus, the director of MIT Computer Science and Artificial Intelligence Laboratory.
She’s talking about her latest research, which describes a new kind of robot that transforms its body to accomplish more tasks. Humans are equipped with tools that let us do lots of things–our hands can play music, work an industrial saw, and write, all requiring vastly different skill sets. But robots, on the other hand, are not quite so dextrous. They can usually only do very specific things with a limited set of tools.
But Rus and her co-authors in a new paper have found a way to make robots much more flexible. The trick? Exoskeletons that fold into a variety of shapes around a central “engine” bot when they’re heated. The exoskeletons act almost like new sets of clothes, and each one enables the robot to do something new: to wheel around, to float in water, to walk, and even to glide through the air.
The exoskeletons are made of a material that has three layers. The middle layer contracts when it’s heated, and by designing sheets of the material that only includes that key middle later in certain areas, Rus and her team created many exoskeletons that fold around the “engine” bot when it’s heated up. The bot can then “shed” each skin by dunking itself in water, which dissolves the latching mechanism that holds the exoskeleton to the robot.
In a video of the exoskeletons at work, a tiny cube-like engine robot quivers and vibrates around a table. It shimmies over to the hot plate, where there’s a sheet of this special material waiting to envelop it. A pair of circular wheels spring up around it, and the bot rolls its way over to a kind of moat filled with water, where it sheds its exoskeleton. The bot can then shimmy back to the hot place to pick up next exoskeleton, and the process repeats. The video ends with the bot triumphantly gliding off the table (before hitting the floor, seconds later).
The morphing bot is the latest in a long line of research into folding, origami-inspired robots coming out of MIT; Rus has also published a paper on how you could package a folding robot as a pill that could be swallowed, deploying it to help patch wounds and deliver medicine inside the body. This particular development could give that folding robot pill a lot more capabilities—if you also swallowed a packet of exoskeletons, the bot could take on different forms when it needed to perform different tasks inside your body. “Origami is another way of making soft flexible architectural bodies that combine new materials and package the capabilities brought by the materials themselves to make machines that are much more powerful,” Rus says.
There are other applications too. Though Rus focuses on small robots, larger bots could also benefit from this idea. If you needed to move equipment over a river, a wheeled robot could take on a more boat-like exoskeleton so it could float across. Scientists could send a single robot to deep space or deep under the ocean along with a set of exoskeletons, enabling a single, simpler bot to do many more tasks.
Rus says that the robotics team has begun to focus on making robots that are suited to interact with humans by making them smarter, more autonomous, and better at understanding what people want.
Her small folding robot exoskeletons are a far cry from the industrial robots found on today’s factory floors, which must be caged off because they’re so dangerous. Instead, these exoskeletons make robots more independent and functional–two important features, as Rus and the rest of CSAIL’s robotics teams work towards robots that can work productively and safely alongside people.