Robot design traditionally separates the body geometry from the mechanics of the gait, but they both have a profound effect upon one another. What if you could play with both at once, and crank out useful prototypes cheaply using just about any old 3D printer? That’s where Interactive Robogami comes in. It’s a tool from MIT’s Computer Science and Artificial Intelligence Laboratory (CSAIL) that aims to let people design, simulate, and then build simple robots with a “3D print, then fold” approach. The idea behind the system is partly to take advantage of the rapid prototyping afforded by 3D printers, but mainly it’s to change how the design work is done.
To make a robot, the body geometry and limb design are all done and simulated in the Robogami tool, where different combinations can have a wild effect on locomotion. Once a design is chosen, the end result is a 3D printable flat pack which is then assembled into the final form with a power supply, Arduino, and servo motors.
A white paper is available online and a demonstration video is embedded below. It’s debatable whether these devices on their own qualify as “robots” since they have no sensors, but as a tool to quickly prototype robot body geometries and gaits it’s an excitingly clever idea.
Like the original, [noniq]’s version is laser cut and engraved, and uses some 3D printed parts. But it does away with the fasteners (that’s 60 pairs of nuts and bolts), and instead uses neodymium magnets to make all the triangle pieces snap together to form the icosahedron globe. The hinges are simply some pieces of gaffer-tape.
This design improvement creates a cleaner globe and also addresses some of the concerns posted in the comments of the earlier build. The design files are available for download on [noniq]’s blog — you need to 3D print some magnet holders and stopper plates, and laser cut the 20 triangle tiles. The stopper plates help ensure that the angle between tiles when it is put together is limited to 138 degrees, making it easier to assemble the globe.
Check out the video after the break to hear the satisfying “thunk” of neodymium magnets snapping together.
Be the hero at your next hackathon with this foldable cnc. When the line for the laser cutter is four teams deep, you’ll come out ahead. It might even be accurate enough to pop out a quick circuit board. Though, [wwwektor] just wanted a CNC that could be taken from storage and unfolded when needed. Sit it on a kitchen table and cut out some ornaments, or hang it from the front door to engrave the house’s address. Who needs injection molded chrome plated numbers anyway?
It’s based around tubular ways, much like other 3D printed CNCs we’ve covered. The design’s portable nature gives it an inherently unstable design. However, given the design goals, this is reasonable. It uses timing belts, steppers, and ball bearings for its movement. The way the frame sits on the table it should deal with most routing tasks without needing adjustment to stay in plane with the surface it’s set-on. As long as you don’t need square edges.
There’s a video of it in operation after the break. We love these forays into unique CNC designs. We never know what new idea we’ll see next.
The unfolding mechanism relies on the torque of the rotors spinning up to swing the arms into place. Once fully extended, a spring-loaded flap folds up, catches on some magnets, and forms an L-shaped structure that won’t re-fold without human intervention.
Under normal flying conditions, quads have a two left-handed propellers and two right-handed ones and the motors spin in opposite directions. In order to do the unfolding, two of the motors need to run essentially in reverse until the frame has clicked into place. They use a sensor (Hall effect?) to detect the arm locking, and then the rotors quickly switch back to their normal rotation before the quad hits the floor. In the video, they demonstrate that they’ve got this so well tuned that they can throw it up into the air to launch. Wow.
Everything’s still in prototype phase, and one of the next goals is “strengthening the arms so they can withstand crashes”, so don’t expect to see these in your local hobby store too soon. In the mean time, you’ll be able to see them in the flesh if you head up to the IEEE International Conference on Robotics and Automation in Seattle that started today and runs through Friday. If anyone goes, take more video and post in the comments?