Researchers at Harvard weren't, so they came up with a way to . To start with, they borrowed a trick from printed circuit microelectromechanical systems ( for short), the technology used in an , for example (aka the thing inside your iPad that lets you ). Instead of cutting out parts from flat pieces of stock and then assembling them into the finished robot, the researchers used a laser cutter to cut the part design into the stock and then sandwiched the pieces together with adhesive.

The researchers used different materials at different layers to create simple mechanical structures---they used a layer of flexible plastic sandwiched between two layers of carbon fiber cut down the middle so the parts could move becomes a hinge, for example.

At this point, you would have the robot assembled, but it's still very flat. To turn the flat robot into a three-dimensional robot, the research team took inspiration from origami and children's books. The researchers designed hinges into the material surrounding the robot, so that when they applied pressure to the top layer of the sandwich, the parts of the robot would move into place, sort of like a fairy-tale castle in a pop-up book. (Check out this .)

From there, the researchers could apply solder to the metal pads designed to lock the pieces together, laser-cut the robot out of the surrounding material, and voila, they had a finished robot, ready for .

This technique makes it easier to build many, many robots in parallel---you're mostly limited by the size of your laser-cutter bed and your ability to line up the layers correctly when you sandwich them together. And researchers are starting to build tools to .