DIY Onewheel – open-source self balancing skateboard(bytesizedengineering.com) |
DIY Onewheel – open-source self balancing skateboard(bytesizedengineering.com) |
With some incredibly odd timing, I documented building a onewheel right before the commercial ones existed, for a 2014 writeup:
https://transistor-man.com/flying_nimbus.html
So jealous that off the shelf hub-motor in wheel assemblies exist now, i had to build a custom hub and dealt with the oddities of planetary backlash, then ended up fitting an early direct drive motor.
There are a lot of hardware variants at different price and quality points but it's a great, hackable, open-source (GPL3) motor controller for smallish motors (in the 24-44 volt range—they typically use a gate drive/power supply controller with a 60V limit).
12S seems to be considered the highest voltage that the original VESC can reliably handle, which works out to 43.2V at 3.6V per cell.
the knockoffs are NOT GOOD and thus even _more_ dangerous to ride because no-one else has figured out how to get the balancing software right.
so, yeah, if you go into this project, know that regardless of how awesome your hardware skills are, the software is the bit that's _really_ going to take a lot of time if you want an experience anywhere close to the official one.
We just had an initial support for VESC NRF/HM10 devices added into Gadgetbridge if this is of interest to anyone fascinated in this subject.
However, the real solution is to just get a fender since riding on anything but clean pavement leads to a lot of dirt being flung around.
All that aside, I would advise anyone who wants to try going this route to watch their ass.
A standard Future Motion developed Onewheel is an extremely dangerous device. I always, always wear a helmet on mine. If you wear a helmet, the device pretty much stops being fatally dangerous, and just becomes a source of rather mild injuries if/when you fall. I rarely fall on mine now, and when I do, I don't get injured due to standard skateboarding/mountain biking pads. All that being said, FM put a TON of energy and learning into their firmware. A onewheel that cruises on a smooth surface is relatively straightforward compared to one that can be reliably ridden in rough conditions, handle bumps/voltage sags/etc gracefully, and just be super durable as well.
I could definitely see an open source onewheel eventually becoming on par with FM's XR. But if you're an early adopter of this thing, be ready to fall, A LOT.
NMC is a type of lithium-ion battery. The cell voltage of the ebike battery he's using is 3.7v, which means it also uses NMC cells.
I learned to ride an InMotion V8 [1] during the pandemic, and although there was a significant learning curve, it's now my favorite way to get around new york city. Definitely wear a full face helmet and wrist pads though if you decide to learn to ride!
0 - https://www.youtube.com/watch?v=h1aRPKyjzj0 1 - https://www.ewheels.com/product/new-inmotion-v8s-728wh-batte...
Also seems super inconvenient to move around. The XR was already annoying to take into shops as it was heavy and long. This is heavier and longer. Though the extra weight might smooth out the ride a bit. Surprised he went for a smaller tire. I feel like a larger one would take bumps better.
EDIT: Whoa, the VESC stuff is really expensive.
Never understood the Segway either.
You get sweaty as hell, and new riders can only ride for short periods of time before suffering lots of fatigue in feet/legs/hips.
Edit: One of my favorite trail riding videos on onewheel
You shouldn't be. Those are motorized vehicles and are not allowed on non-motorized trails.
Doing this with mass transit would take an hour, walking would take an hour, driving would be a pain because of parking.
It's great for all sorts of little trips like this, probably up to a 6mi round trip (I have the pint).
They can't produce any torque at zero speed, they can't smoothly reverse direction, they likely can't produce enough negative torque at higher speeds, and their control bandwidth is probably inadequate for anyone but an extremely skilled rider.
1: https://dailyhornet.com/2021/onewheel-lawsuits-pile-up-after...
I was padded up for both falls but still sustained a sprain to an ankle and some pretty mean scrapes to my shoulder and arm.
My worst fall was due to the motor cutting out on a moderate acceleration uphill climb from stop. This is not unusual on the OW but is normally associated with a lower battery level.
I was pretty good with it, but in the end I could justify the potential for falls once every 100 miles, let alone 50.
They are fun to ride, though.
I've gone up to 24 MPH (on flat) when I had one, and have hit the ground going twenty. I'm honestly not sure more speed is a good idea as it just takes one little crack in the road you weren't anticipating to throw you balance off.
After all, when you brake hard with a car or motorbike or bicycle, it's the front wheel, well in front of the centre of mass, that does almost all the work.
In a single wheel vehicle, the wheel well in front of the centre of mass.... isn't there. In a unicycle that means you're flying off the front (it's even worse in a monowheel) so you'd better not be going faster than a man can run.
your stopping speed is limited by how fast it can decelerate you, which is essentially the same as how fast it can accelerate you. it's not super fast to stop, to be fair, but neither is a bicycle going at high speed (though I'd expect the bike to be a little bit quicker to stop).
The smaller wheel is a bad idea. Period. Can't fault the heavier weight though. Future Motion machines their aluminum rails from single billets. It's not something that you can replicate easily without tremendous capital expenditure.
I'm planning on buying the new GT soon, but it's even heavier, and my god is it awful carrying those things around.
When you are going so fast that the motor is at its brink, the onewheel will raise the nose as a warning. Ignoring this will toss you off the board, maybe that's what people are experiencing?
Mine cut off semi-randomly a couple dozen times when I was well past the 300 mile mark. The worst/most annoying cases would be when trying to re-engage it when the traffic light would go green, but the onewheel wouldn’t re-engage and it’d just look like I was tripping forward in traffic. I’d have to step over to the curb and restart it a couple times before it ‘worked’
It was definitely the most fun I’ve ever had commuting, but the fact that I couldn’t trust it to simply just not shut off on me in traffic made it feel pretty impractical.
Apparently a couple causes for this could have been a bad battery and also a bad footpad. For now, I’m just sticking with my ebike, since a battery failure there is a bit less catastrophic!
Well, now you have. I ride OneWheels and one of mine (all stock except tire) has developed an issue where it does randomly nose dive, even at medium speeds (10-14mph). I'm logged about 2k miles and I'm well aware of when the board can nose dive due to pushing too hard up a hill or into a headwind. I've had 4x nose dives on that board (specifically in the last dozen rides) that were not caused by any of the standard issues. It seems to be a footpad sensor issue since after the dives, the footpad won't engaged fully without some well targeted "precursive maintenance."
Personally, I think a lot of people ride them way to fast for the amount of gear they wear and their skill falling safely in that gear. I like to ride slower and carve. It's more fun and much harder to break a bone if you know how to fall well.
I’ve been tempted by an ebike and have a fancy bike for long cycling rides, but the Onewheel is just easier for lots of quick small stuff. Plus it’s fun.
1: https://www.tapeswitch.com/ 2: https://transistor-man.com/PhotoSet/flying_nimbus_MKIII/P108...
It's surprisingly intuitive once you get going.
Leaning back is not an option once the motor stops pushing the wheel towards you - it’ll roll and then tumble to a stop much more quickly than air resistance slows you down, so you’ll fly off the front.
I’d like for there to be a magic solution to this problem since the size of an EUC is very attractive. Rolling to a safe stop on my electric scooter is preferable in the meantime.
either way, safety gear safety gear safety gear. especially since basically all these electric personal mobility enhancing whatsits are horrifyingly injury-prone compared to anything the size of a bike or larger.
I'd say in the active group of people there were maybe 2 that this happened to, out of maybe 10-20.
You don’t, and the trails I ride on allow them. In Boulder County, that’s not the case. I ride in other counties. But thanks for the lecture, dad.
Regardless, it makes zero logical sense to ban a 2 horsepower, silent, electric motor vehicle that is lighter and slower than a mountain bike, but allow mountain bikes. It’s hippie logic: horsepower produced by human legs augmented by fancy mechanical gears and chains is “natural” enough to allow, but if it’s powered by something else, ban it before the heathens desecrate the sacred space.
Thankfully, most of Colorado is people stoked about what they are doing, instead of pissed about what others are doing. You fall into the latter category. Boulder is your kind of place. Meanwhile, I’ll be somewhere else menacing the public safety with a 25 pound vehicle with a top speed of 18 mph.
Your disrespect for public land deserves to be called out.
Please explain to me how I’m “disrespecting” public lands? A Onewheel is as quiet as a mountain bike. It’s slower. It’s tire distributes weight on a bigger surface are and doesn’t ruin the trail with ruts. I don’t deserve to be called out, you just like rules and lording them over others. Go tell someone else what to do, Karen. Unless you obey the speed limit to the letter everywhere you go, you have no leg to stand on. After all, if I go 57 in a 55, I’m “disrespecting public roads” in your logic.
That being said, in places that don’t allow them, the rangers shrug, say “cool, glad it’s slow and doesn’t disturb wildlife” and go on about their business. I had a ranger near Leadville trying mine, and he later bought one. Boulder County is a stark exception. They were one of the first places in USA to ban mountain bikes from their trails in the 80s. An organized, well funded lobby pushed for that to change and got the ban removed. Unfortunately, there is a small minority of citizens who gleefully will call the police if they see you on a mountain bike trail with an LEV. They won’t say anything to you, they’ll dime you out as soon as you get out of sight. Boulder rangers will give you a court summons. I was on a trail in the summer when a fire had made a smoky haze. The trail was deserted, due to the poor air quality. A member of a super expensive ashram saw me and my son from a balcony, and called the rangers. I went to court. The judge thought it was absurd, openly stated that the motorized vehicle ban was enacted in the 80s to bar gas powered ATVs and dirt bikes, and fined me 100 bucks. She said it was the same fine a mountain biker gets if they go on a hiker only trail.
The Karen in this thread is one of these people who don’t like sharing trails. It’s not about the motors, it’s about their belief that motors will bring the_wrong_kind_of_people. The kind of people who weren’t wearing masks outdoors on windswept, sparsely populated trails last summer like they were (glad they finally caught up with rest of us and science and stopped shaming people who understood how aerosols work).
FYA Boulder has a few trails explicitly designated for ebikes, so they are slowly evolving.
It 100% is about motors. Get a mountainboard if you want to ride legally and stop acting like a martyr.
> E-bikes are not allowed on trails designated for non-motorized use. Non-motorized trails include trails like hiker, horse, or mountain bike trails. E-bikes, like other motorized transportation, also are not allowed to travel cross-country off trail. There are no exceptions.
MTB: Non-motorized
Dirt Bike/E-Bike/One Wheel/Jeep: Motorized
For example, an audible tone the moment it shuts off the motor while underway.
There are other design changes that could reduce the danger of a nose dive that 3rd party manufacturers have pounced on including small wheels that allow the product to potentially slow instead of come to a dead stop when an edge hits the ground.
I don’t know what product liability is for continuous mounting evidence that an existing design is lacking obvious safety feature and choosing not to make changes or acknowledge this.
But I suspect ultimately this will end in a class action suit.
I assume these are the wheels you're talking about[1]. Pretty ingenious idea, although it does mess with the look of the board
[1]: https://www.etsy.com/listing/1069745398/onewheel-xr-safety-w...
Expectations for safety have changed a lot,too. I raced ski team in high school. Helmets were optional and very few rec skiers wore them.
Now it seems unusual to see someone without one.
I’m aware of the haptic feedback the board is supposed to give when it is getting tired, though there are many claims of it not being produced prior to a nose dive.
Yes that product you linked is what I was describing. Note their description describes nose dives on the OW as “inevitable.”
If it has the ability to monitor battery life then it can certainly do stuff like emit an impeding dead battery warning tone and then gently decelerate to a stop.
Though I bet its an issue where the battery level is simply monitored via voltage. So lets say a 15% charged battery has enough current to push the rider along on level ground, BUT, the moment the rider hits an uphill, the current increases beyond what the now weaker battery can provide, the voltage drops below the battery threshold and the battery protection circuit shuts down. Very unsafe design.
A proper design would allow the battery and motor drive to cooperate so when the motor current demand rises to maintain velocity, the battery pack can tell the motor, sorry, I cant give you anymore and the motor drive can then decelerate or simply refuse to continue accelerating.
I do not have experience with Onewheel XR, but pushback on the Pint series is rather noticeable and hard to ignore when you hit set speed limit. Onewheel XR is said to have weaker pushback.
These are good thoughts though even in your solution I suspect it points toward the idea that the design is fundamentally unsafe.
The reason is if the motor decelerates you still must be prepared for your weight to shift, even gradually.
I'm aware that Boulder has different rules than most of CO. JeffCO allows Class 1 bikes on MTB trails [2]. A OneWheel isn't a Class 1 because it isn't pedal assist.
You disrespect public lands by violating the rules that govern them. There are legal ways to skateboard on MTB trails, but they don't include a motor. Earn your turns, or stick to paved surfaces.
[0] https://www.fws.gov/refuges/biking/e-bikes.html
[1] https://www.federalregister.gov/documents/2020/11/02/2020-22...
Or... I’m going to enjoy Colorado and the fact that most people don’t have a need to be hall monitor busybodies, and keep doing my thing.
I’ll be stoked on what I’m into, and leave it to others to be pissed about what others are doing.
You're just selfish and disrespectful of public lands.
The design of self-balancing PEVs isn't fundentally unsafe, but it (like most sports and means of transportation) does carry risks that you should be aware of and compensate for.
By the way, I do a ton of riding on Jeep trails and roads as well. But the challenge isn't on par with single track.
The intention of banning "motorized" vehicles was never about the power source itself, but instead the negative externalities created by the power source. It was about preventing the negative externalities that "motorized" created in decades previous to the current one, when virtually every motorized vehicle capable of being on a trail was powered by an internal combustion engine. With ICE, you have to have a ton of horsepower (compared to EVs) to get enough torque to handle trails. There was no such thing as a "motorized" vehicle that was silent and non-polluting. They had top speeds in the 40s and up, and due to the engine are hundreds of pounds and therefore dangerous, on top of the noise and exhaust.
You've ignored the "spirit" of the law, or the reasoning behind why they were put in place. You've fixated on a technicality, out of a misguided sense of purity, where everyone on the trail needs to "earn" the right to be there through direct physical effort. The people who banned mountain bikes had the same argument as you, viewing any form of wheels as "cheating". It's a quasi-religous viewpoint, it's not logical, and therefore you are forced to resort to technicalities without explaining the logic of how a onewheel makes the trails less safe, less intact, noisier, less hospitable to wildlife than a mountain bike does. You have no answer to this. Instead of examining your viewpoint, you stand on the letter of the law. It's a sign of a very weak position.
> You're just selfish and disrespectful of public lands.
Please name a single way I am hurting anyone else on the trail that differs from a mountain bike. Name a single example. What does my onewheel do to interfere with other people's use of the trail that a mountain bike doesn't? You may have an extremely insightful point that I haven't thought of. If you do, it might change my mind. I don't have any desire to "disrespect" public lands, or hurt others. How am I hurting others? How am I hurting the trail?
