Why does the board have to lock up @ max speed?



  • I'm not an engineer or mechanic, so I'd love to get some feedback from you all... I know there are some rocket surgeons amongst us that could shed some light on it for me.

    Last weekend, I had my first hard fall on the OW. Thankfully, I seem to have come away with no major injuries save a bruised ego, ripped shirt, bruised/sprained wrist and a nice chunk missing from my left palm (aka my mistress).

    For me, the accident happened as I was riding down the sidewalk. A bike rider, also on that sidewalk (=/) was coming towards me so I dipped off the sidewalk on to the road and in that transition, with my eyes on the road ahead (cross traffic) and the bike rider, I didn't see a small pot hole in the road. I took the pot hole at speed (10mph +/-) and it threw me off balance. I had to lean forward to regain my balance, and in doing so, quickly pegged the speed on the OW causing it to stop and send me tumbling forward.

    I tried to run it out but that wasn't happening... I braced with my palm, then forearm, then tucked and rolled a bit over my left shoulder and came to a stop. I had a helmet on but I rolled gracefully enough that it didn't touch the ground. My palm got the worst of it, with a little road rash on my forearm and a little less on the back of my shoulder.

    The thing is... if the OW didn't hard stop when you peg the speed... if it simply cut out and coasted... I'd have regained my balance and kept on trucking. The fact that exceeding the top speed causes a hard stop is what caused me to go tumbling. Hindsight being 20/20, I should have been wearing wrist guards... I purchased some earlier in the week and they arrived yesterday... I'm thankful I didn't go tumbling in front of a car and that I am strong/agile/lucky enough that I didn't break my arm or wrist. My hand hurts and I've been mostly useless in the gym this week but all things considered I'm grateful.

    Is it/would it be feasible to have a mechanism that allowed for coasting when the motor cuts out? Is there a mechanical/engineering/cost reason that would make that solution unrealistic? talk amongst yourselves =) and thanks in advance for reading/responding.

    Have a terrific weekend all.



  • @OriginalEric Couldn't tell you, but I agree that it seems wrong.



  • It feels wrong too



  • I agree with everyone so far. This is a great question i would like them to answer as well.



  • I have launched at over 15 mph at least 5 times the first two weeks I got it. Heres my theory or anatomy of a crash. When it takes off it gets to the speed where you start to wobble causing your foot to lose contact with the sensor which shuts the motor off which makes the nose tip forward with your weight and contacts the ground skidding as you fly like Superman towards the pavement. The key is to stay centered and don't lean forward. Get in the habit of leaning back slightly and use your ankle like on an accelerator and gently push to speed up. I am comfortable at just under 12 mph using this method. I use a biking app on my windows phone that shows top speed and map tracking. I use the elbow pads that protect a portion of your forearm too.



  • No, I just did it for the first tjme, what it is is you guys are pushing through the pushback. I was trying to test the speed of the device. I was being an idiot. And I knew the limits, I was trying to push it. I was in fact had my center of mass behind the wheel, but was pushing down to see if I could squeeze just a little more speed, then boom, it locked up and it launched me. But, the board was clearly telling me to slow down.... The people that keep getting launched, are not listening to the board.... Your just pushing forward. :). I ended up with some nasty road rash :)



  • @Aaron-Broward-FL
    Sounds awesome. The safety feature that doubles as an anti-safety feature.



  • Okay, my 2 cents:

    First of all, I don't think you would be able to coast at all, even if the wheel didn't lock up when cutting out. Just try to keep your balance on the board when it isn't turned on; it's almost impossible.

    Second, the reason I think the wheel "locks up" is because of the regenerative breaking, which makes the friction on the wheel super-high when the engine cuts out.

    Does that make sense?



  • I might be wrong, but for me it seems that it is already possible to deal with an high speed cut-of from the motor. at different occasions i managed to "recover" to regular riding again by just manually rebalancing the onewheel instead of jumping off and running it out.

    e.g. when close to top speed and pushing to much on the front sensor side (because of hilarity or because of an unexpected road hole) it happend to me several times that the board stopped balancing for a moment. but if I managed to quickly react correctly and counter-balanced it, it seems like it rebalanced and I was able to continue the ride.

    I even had it two times that I was already sliding on the front bumper pad for several meters at (more than) top speed, but was able to rebalance it until the onewheel rebalanced and continued to work fine.

    is it just my impression, or have some of you experienced the same thing?
    if so, all we need is some good practise and to stay cool instead of jumping of and running it out...altough it is risky of course;-)



  • @cr4p

    Happened to me once when I pushed it a little and was able to recover.
    I don't think it locks at top speed.
    I think it locks at a steep angle which you wouldn't be able to recover from anyway.
    Try it in hand. When it tilts to certain point, it locks.



  • You guys are not taking about the same thing, I have hit a bump, had the back of the board bottom out, and I was able to rebalance. What we are talking about is... Flying along at top speed at a constant rate not accelerating... And then without warning, like getting side swiped by a bus your face is in the pavement about 10 feet in front of the board. There is NO opportunity to correct anything. It's the equivilient of what you could imagine driving into a 1 foot high concrete wall at top speed would be like, but, with no warning. :)

    And, there was a comment that made sense, above, the board may not be locking up at all, the engine may just simply be cutting out, if the board is dying and there is no self balancing happening, the forward momentum of the board would carry you into a face plant.... So, that is clearly what is happening.. Because it would make no sense to design a lock up. So what is happening is if you push past the pushback, the board dies and your momentum carries you forward the board nosedives immediately, just basic physics there, it feels like someone hit the breaks, but that's the self balancing gone bye bye..

    By Joe I think we got it. :)



  • One aspect I'll bring up is that I don't think the board should be able to completely seize when the sensor pads experience a disengagement of pressure while moving. I think the board should remain active and provide a gradual deceleration of the device rather than the complete stop of the wheel rotation on pad disengagement while in motion. When I turn on the board, and don't have pressure on the foot pad, the wheel is very hard to turn, but I can imagine that accidentally having a foot slip off and have the boards wheel stop immediately can't do the rider any good. Maybe there is a way to have the board decelerate slowly for a given time period until while remaining the balance assistance or at least until pressure is put back on the sensor. Then again, this idea would have to only be put into effect while riding above a certain speed because if it was active all the time, it would be very difficult to get on the board and begin riding from a stand still.



  • @T-CAT When the board is moving you actually have to lose contact with one of the sensors for quite a few seconds before it cuts out. (edit: by "quite a few" I mean 3 or 4.)



  • That is true, but the boards wheel still immediately stops instead of gradually decelerating and balancing. This can be a safety concern if the both pads were to fail (or the associated electronics), or someone's foot is off the pads for just a tad too long, as the rider would go flying superman style. A gradual deceleration while providing balancing assistance would likely be the safest bet, along with having slightly wider foot pad sensors. Having four sensor pads (especially two strips of the ones on there now), but positioned horizontally instead of vertically may work. So, take the blue area now with the sensor pad (two) and lay that horizontal on the top portion of the wood plank, and another strip (of two) and place that on the bottom part of the wood foot plank. :)



  • I wish the sensors could be angled. Like the bindings on a snowboard. Riding goofy and turning right is slightly awkward.
    I think they designed it this way for ease of dismount. I peel my foot and sometimes start drifting back and then remount it and just jump off with both feet anyway most times.



  • @wheeler really? I find it a breeze turning right while riding goofy



  • @wheeler good call on the idea of an angled sensor pad. I always think that too. I ride very duck footed. I guess they would have to angle them backwards for me because I'm goofy foot though.



  • has anyone else noticed that it can freewheel? my wife and I have both disengaged the sensors a bit too early when coming to a stop and had the board freewheel out from under us and bam, right on our backs. we have both only made that mistake once! also I want to add to the conversation that I have accelerated too fast and went through pushback twice and just ran it out and once I think that I broke contact by squirming my foot around and I got launched with no possibility of running it out so I think that the responses are different.



  • The only thing that makes logical sense is they gotta be working on the lock up problem, but its something with the hardware like a cut-off of some kind with the DC motor that's supplied by others and thus can't just be tweaked with a few lines of code. It really seems to be the main thing holding these boards back from mass acceptance and unequivocal endorsement by current riders, I suspect its only a matter of time before we see a motor upgrade that definitively resolves this issue.



  • I noticed mine cutting out when I attempted to go over a curb a couple times. I was going too slow so the back of the board hit the curb as I was going off the curb but my feet didn't come off the sensor so I'm confused why It cut out.



  • @SeaP90d said in Why does the board have to lock up @ max speed?:

    The only thing that makes logical sense is they gotta be working on the lock up problem, but its something with the hardware like a cut-off of some kind with the DC motor that's supplied by others and thus can't just be tweaked with a few lines of code. It really seems to be the main thing holding these boards back from mass acceptance and unequivocal endorsement by current riders, I suspect its only a matter of time before we see a motor upgrade that definitively resolves this issue.

    I agree only lunatics and adrenaline junkies (like myself) may sign off on riding a board that mysteriously cuts out and leaves an uncontrollable wide open window for major injury or death beyond the already inherent dangers that exist. It would be alot more comforting knowing that as long as I don't do A,B or C I won't have to deal with an unexpected cut out.


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