2015 was two years ago, and to the surprise of many, we actually had hoverboards at the time. Of course, these weren’t Back to the Future-style hovering skateboards; they were crappy two-wheeled balancing scooters that suffered a few battery explosions and were eventually banned from domestic flights by some carriers. But oh boy, there were some funny Vines of these things.
The popular and cheap electric unicycles and hoverboards that have been swimming across the Pacific from the great land of Ali Baba for the past five years are based around a single, cheap controller board. This controller board is built around the STM32F1038T6 microcontroller, and are able to control a pair of three-phase brushless motors. The teardown began on the electric unicycle forum and was completely documented in a GitHub repo.
The Open Source firmware is now mostly complete, although the necessary self-balancing function doesn’t work. We’re thinking that’s alright; with this new firmware, these electric unicycles have a crazy amount of torque and could be the basis for a few very cool builds. You can check out a video of this torque below.
Since then it has been completely redesigned and now has a super fat kite-surfer wheel, a front crash skid with damper, and a variable geometry which allows it to steer properly despite just having one wheel. It does this by allowing the rider to shift their position relative to the wheel, instead of the seat always being rigidly locked directly above the axle.
That steering is a pretty clever upgrade, but we do wonder if the new crash skid will have an atlatl effect and really launch the rider in a crash. Our gut feeling aside, it is designed not to plant itself in the pavement, but to slide along (without ejecting the rider) until the vehicle loses all momentum.
There is something about self-balancing unicycles that attracts experimenters, each of whom takes a different approach. We see everything from this device constructed mainly from a Razor Scooter to this more polished-looking unit based on an earlier Segway clone design. [XenonJohn] reminds us that “there is still much to learn in this area and you can genuinely innovate even as a hobbyist. Also, you can only do so much on a computer, you then have to actually build something and see how well it works. [This recent test] shows what you can do if you just keep on experimenting.” Video of the test drive is below.
Focus Design sent us a video of their self balancing unicycle (looks like they’re taking on Focus Features too). The electric machine moves at 8MPH and lasts 1.5hrs on a single charge. It only weighs 24.6lbs. They say that new riders only need about 2hrs. practice. They’re building ten units to start for $1500 each.
Electric unicycles are nothing new to our community. We’ve long been fans of [Trevor Blackwell]’s electric unicycle. [Trevor] spent several months learning how to ride a regular unicycle before he could properly debug the electric version. There are several other designs out there: The Einrand-Fahrzeug has a wide wheel to make balancing easier. The eniCycle includes a steering mechanism. The Uniquecycle has a brushless motor in hub for a compact design. We did a roundup back in July that covers these plus many other motorized unicycle concepts.