A before (left) and after (right) look at one "robot" fresh from the oven.
You may remember tuning into the self-assembling cube set called M-Blocks that made its way out of MIT last year. Here's a quick refresher: The modular robots had the ability to change their geometry based on the task at hand with help from an internal flywheel, magnet power and commands transmitted via computer over a wi-fi connection—which made for a hands-free, mechanical dance of sorts, much to the excitement of the Internet at large. Now, another group from MIT—the Computer Science and Artificial Intelligence Laboratory (CSAIL)—has introduced a new mechanical must-see in a similar self-assembling form. This time, the magic happens when you heat things up.
The CSAIL crew introduced their most recent work on bakeable robots at last weekend's IEEE International Conference on Robotics and Automation in Hong Kong. The research incorporates printed robot parts that morph 3D components once they reach a certain temperature. The scale might be small for now, but it gives us a great way to rediscover robotics with a rejuvenated childlike appeal, in an odd Easy Bake Oven kind of way.
The video MIT has released is short, sweet and only hints at the possibilities, starting with the basic shapes such as perfect coils and formations. Check it out:
Thankfully, the research team behind this discovery (led by Daniela Rus, MIT's Andrew and Erna Viterbi Professor of Electrical Engineering and Computer Science and CSAIL director), gives us a little more insight into the work with two papers on the project:
One paper describes a system that takes a digital specification of a 3D shape—such as a computer-aided design or CAD file—and generates the 2D patterns that would enable a piece of plastic to reproduce it through self-folding. The other paper explains how to build electrical components from self-folding laser-cut materials. The researchers present designs for resistors, inductors and capacitors, as well as sensors and actuators—the electromechanical "muscles" that enable robots' movements.
But isn't anything going to fold into itself to some extent when heated? Shuhei Miyashita, one of the papers' co-authors explains why this isn't just some origami parlor trick:
The key difference in the new work, explains Miyashita, is a technique for precisely controlling the angles at which a heated sheet folds. Miyashita sandwiches a sheet of polyvinyl chloride (PVC) between two films of a rigid polyester riddled with slits of different widths. When heated, the PVC contracts, and the slits close. Where edges of the polyester film press up against each other, they deform the PVC.
Imagine, for instance, a slit in the top polyester film and another parallel to it in the bottom film. But suppose, too, that the slit in the top film is narrower than that on the bottom. As the PVC contracts, the edges of the top slit will press against each other, but there will still be a gap between the edges of the bottom slit. The entire sheet will then bend downward until the bottom edges meet as well. The final angle is a function of the difference in the widths of the top and bottom slits.
If you're looking for more self-assembling robot eye candy, check out this video featuring the aforementioned set of robotic, self-grouping cubes: