It’s amazing how much the BB-8 droid from the upcoming Star Wars film has captured the public’s imagination. Part of this is due to the fact that the astromech droid’s design is so unusual, and that its workings are a mystery. This has sent robot builders to the drawing board to try and work out the various ways this bot could work. And people are coming up with many different clever designs. It’s as if J.J. Abrams and his conceptual artists issued a design challenge to robot hobbyists, one that they’ve eagerly accepted.
UK maker James Bruton, whose ambitious 3D printed robotics projects we’ve covered here before, has a recent video series detailing his version of a BB-8. James began his project soon after seeing the original Episode 7 trailer, featuring the BB-8, and so he had few clues to go on.
Now that he’s done, and an actual real-world version of the droid has premiered at Star Wars Celebration, Anaheim, there are many things that he’d do differently, and he may, in a second version of the build.
One of the things that I love about Bruton’s project videos is that he explains his design process, prototyping stages, the actual build, and the problems, troubleshooting, and fixes — all in clear and straight-forward detail. And he’s not afraid to admit mistakes, kludges, and downright fails (and thankfully, there are few of the latter). Regardless of what the project is, you really learn a tremendous amount about mechanical and electrical engineering, 3D printing, and microcontroller programming.
As you might imagine, this project was a serious challenge. The BB-8 astromech droid in the trailer is comprised of a ball with a domed head magically balancing on top of it. James came up with a rather ingenious but fiddly design involving putting everything in the head dome and using the dome to drive the ball beneath. He used a lightweight polystyrene ball for the body, a Plexiglas dome for the head, omniwheels, and an Arduino Mini Pro for the brains.
Four omniwheels sit beneath the dome and move the ball to move the entire robot. A Sparkfun LSM9DS0 9-axis accelerometer/gyro/magnetometer is programmed to keep the dome balanced on top, dynamically reading its position and adjusting to stay on top of large ball moving beneath it.