Thrown off after nosedive with no pushback warning (nose dive, nose-dive)



  • An experience and some questions:

    ~Background~

    Been riding for a few weeks, always in classic mode, new board so new firmware. Have ridden on smooth pavement, rough pavement, hard dirt, soft slightly muddy dirt, grass. Until this weekend never had the OW do something that I didn’t understand. When first learning I didn’t understand how to work the sensors so I was run over or thrown off in reverse a few times. I believe I now have a good handle on these and can stop and dismount easily in 1 spot without really thinking about it. I don’t ride too fast and don’t think I’ve felt pushback.

    ~The Experience~

    This Sunday I thought I would get in a ride before the rain started again here in SF. Streets were dry. I live in some moderate hills and cruised around and up and down not over 6-7mph. Then, with 60%+ battery remaining, I was going straight on a relatively flat street, probably a bit slower than my average speed. While it happened pretty fast, my recollection is that without any warning and without losing my balance. the nose of my board ate the pavement. Wearing helmet and wrist guards, I launched forward – as a snow sports guy I put my right (forward) arm out by reflex. The board continued to travel forward at a 45% angle to the right, thunking loudly against a garage door where it stopped. I dislocated my right arm and spent the rest of the day in the UCSF Emergency Room high on Dilaudid and Fentanyl.

    ~Questions~

    Obviously I would like to understand why this happened. From reading this thread I see some theories but the root cause is unclear. Given the occurrence from time to time of similar experiences, I believe it would be prudent for FM to provide collection of and selected access to real-time actuator/sensor data. If the OW lacks sufficient memory I don’t think it would be hard to log across Bluetooth to the phone. I also think it would be in the company’s best interest in order to improve and refine the behavior of the OW. I would understand a potential reluctance based on litigation risk but it needs to be done and the lawyers would just have to do their best to protect the company, as they do in all motor vehicle industries.

    My second question is somewhat higher level. When I am cruising on pavement at a consistent speed in classic, the board sometimes feels like it is leaning a bit forward for a few seconds then leaning a bit back for a few. I am trying to stay balanced over the wheel and not rock forward and back, but I am still getting this feeling. Anyone else find this?

    Closing note to FM: I strongly encourage you to follow up on this issue. Right now you have a loyal set of users who are willing to take some bruises for the company and the product; we are certainly not looking to damage the company. Help us to help you improve the behavior of the product and make it more attractive to the mass market. If you need some help or ideas, just let me know. Thanks!



  • @dj.rknz Ouch....that sucks. Sorry to hear. Hope your arm/shoulder heals soon.

    I am on this thread with a couple of similar experiences and a similar request to @onewheel. I hope they do follow up and/or let us begin to collect the data. After each of these "events", it has taken me longer and longer to trust the board and ride again. I love this product and don't want to loose faith in it.

    Regarding your questions, the forward/back thing goes away as you ride more. I suggest trying Extreme mode. Seems to be a better (albeit less carvey) ride.



  • I was riding today and rode on and off for about 3 miles. On coming back to my car, I was heading up a slight incline and going what I estimate to be between 6-7mph.. All of a sudden the wheel just locked and I happened to nose dive pretty bad. Thankfully I was wearing my wrist guards, but my arms got shredded pretty bad. I've been trying to analyze what happened. At the end of the day, until OW can give us more recordable data.. We are not going to be able to prove whether it's the rider, board or conditions.

    I would happily build an alternative app if FM/OW would open up their data api to bring the sensor data into another app.

    Until we get some data collection, we're shooting in the dark as to why these stop the way they do.

    OK back to scraping asphalt out of my arms. Cheers



  • @Mynticelx said:

    I was riding today and rode on and off for about 3 miles. On coming back to my car, I was heading up a slight incline and going what I estimate to be between 6-7mph.. All of a sudden the wheel just locked and I happened to nose dive pretty bad. Thankfully I was wearing my wrist guards,

    Same thing here yesterday.. Pretty sure through no fault of my own.. It's a bit disconcerting when these things happen..



  • The Onewheel is an inherently unstable powered unicycle, not a self-balancing device. All of its sophisticated sensors and controllers merely give it a way to respond to the control input from the rider. It's more stable than a traditional unicycle because the control system can make more precise adjustments to the wheel more rapidly than humans can by turning a crank with their legs, and because the tire is wide. Aside from that, you're still learning to balance a unicycle, but this one goes a lot faster.

    New riders have to work hard just to avoid falling, and slow speeds feel fast. Pretty soon they get the hang of balancing. They get the hang of steering. Their confidence improves. Slow speeds feel very slow. They don't feel like beginners anymore.

    The stability and power they get from the motor and electronics come with a trade-off: Unlike legs turning a crank, the motor of a Onewheel isn't wired into the rider's brain, so the rider's awareness of the motor's limits is vague. As the rider approaches those limits, the motor loses its ability to improve stability, or even to provide useful feedback to the rider.

    At that point, the rider has become the pitiable fool (and let's be honest: We are all this fool) who deliberately rode a powered unicycle in Extreme mode (so that it would be even less able to protect the fool from himself) at a higher speed than he can safely fall...

    Anyone with a defective board should certainly have it serviced. The rest of us should understand that we're learning how to ride a powered unicycle at unsafe speeds, and we should adjust our expectations accordingly. It's not safe, nor is it easy, and that's part of the appeal. If you're taking high-speed nosedives, congratulations! You're no longer a beginner! Here's another piece of good news: You're not an expert yet, so you still have lots of cool stuff to learn.



  • @badcheese nailed it. (and this is why you should always wear a HELMET.)



  • @badcheese While I agree with everything you said.. There are some of us that were till in classic mode that this has happened to. I'm not complaining and don't necessarily believe it's the fault of the OW... But just like a unicycler (if that's even a word) would check their mecahnical parts to their bike, I would like the same for the OW. Stream me the data of the ride to understand why these things happen. What as the speed, gyroscope angle, engine rotation, etc. It's not too much to ask to FM to open that up to its riders.



  • @dj.rknz I would like to know that someone in a senior management or engineering role at FM is reading this thread. Could you please confirm that this is the case? Thanks very much.



  • @badcheese I'm afraid I must disagree with Mr Cheese on this. A unicycle is an analog device under the direct and absolute control of its rider. Its instability and difficulty are due entirely to the physics of its design. This is the reason it costs $150 instead of $1500.

    A OW, on the other hand, is a digitally intermediated, highly-abstracted ride by wire system that depends heavily on behaviorial models embodied in software along with a complex network of sensors and actuators. The fact that it is not self-balancing is immaterial; more material are the facts that the behavior of the system depends almost entirely on the assumptions and judgements of the system's designers, how these are embodied in software and component selection, system testing and revision, heavy end-user input and honest reassessment, and more testing and revision. In this regard a OW is more like a fighter jet than it is like a unicycle. As with the jet, there can be strong perceived pressure on management to "bury the data"; this must be resisted at all costs, particularly with a system as immature as the one we are talking about.



  • @dj.rknz said:

    [...] This is the reason [a unicycle] costs $150 instead of $1500.

    A cheap unicycle costs $150. What we have is a fancy unicycle. Here's a guy who spent $2800 on his unicycle, and it doesn't even propel itself:
    http://www.unicyclist.com/forums/showthread.php?t=117532

    A OW, on the other hand, is a digitally intermediated, highly-abstracted ride by wire system [...] the behavior of the system depends almost entirely on the assumptions and judgements of the system's designers [...] In this regard a OW is more like a fighter jet than it is like a unicycle.

    The OW is far from ride by wire. With the right software, we could replace the pilot of a modern fighter jet with a corpse and still fly fancy aerobatic maneuvers. Put a corpse on a OW, and the best you could hope to do with software control is maybe drag it in a straight line for a short distance - assuming the fender kit keeps the corpse from jamming up the wheel, etc. (I'll leave the remaining details as an exercise for the reader...)

    Also, keep in mind that pushback just means the wheel speeds up slightly in an effort to get a little bit ahead of the rider's center of balance. The most extreme thing about Extreme Mode is that the pushback is extremely subtle.



  • @badcheese I think what @dj.rknz meant when he said "ride by wire" is that the rider's physical input does not translate in a direct mechanical fashion to the control of the vehicle, a la a bicycle or unicycle. The input is translated through sensors and processors and then fed as binary information to the motor control unit.

    There is a term in motorsport, "brake by wire" which means that a processor controls the brakes based on input from the driver vs. direct mechanical braking where depressing the pedal engages a series of mechanical bits to cause the brakes to be applied. The "feel" and feedback of a "by wire" mechanism isn't going to be as straightforward as one where direct mechanical input is involved. With a vehicle as advanced and new as the OneWheel, there is going to be a lot of room for development to improve all of the things. It would be very nice if FM would release some sort of API to at least monitor the vehicle's data output. Tasker integration would also be incredible, but I don't see that ever happening. I'm afraid that they won't open up even the data output of their proprietary software any because of the looming threat of Chinese knockoffs. You know the Trotter is only the beginning of that shit circus...

    But that being said, I agree with you both on your major points.



  • Wow: I ate it bigtime in a nosedive scenario on pavement and been on crutches for weeks. I sent the board back to onewheel after they told me it may be defective but now im told its working fine. They are sending it back. This thing did the dive 2 times.



  • @smashdunk Expecting the company to respond to any questions that are not real simple and generic is impossible. The have a firewall up to prevent us from talking to anybody except each other re: anything technical, and this toy is technical as hell. All it is is software.



  • @powder Sorry to hear that! But nosedives typically happen when people lean forward and put all of their weight on the front, rather than keeping their center of gravity over the wheel and tilting the board with their feet to speed up or slow down.

    The OneWheel uses your body and the laws of entropy [Edit: INERTIA, not entropy] to keep itself level by moving in the direction the deck is tilted, causing your body weight to shift backwards. But the OW can no longer use your body to stabilize itself if you're off balance (which is what happens when you put your body weight on the front of the board). All that will happen is the nose will hit, the board will stop, and you'll get thrown onto the ground, hard.

    If you stay centered, the chances of this happening are significantly lowered. And a lot of the times, if you do nosedive, you'll be able to either pull out of it, or run it out.

    Anyway, hope you feel better and can jump back on that horse! But if you do... stay centered!



  • @thegreck I'm sorry, but I have to correct you about the "laws of entropy" thing. What you're talking about are the laws of Newtonian Physics. Entropy is some heady stuff about the universe's tendency to ever more chaos.



  • @bmtka Oh, sorry... I meant inertia, not entropy! I had to re-read my post to even believe I had said that.



  • I'm scared to get back on the board at least on pavement cause no pushback warning and I've been thrown down twice now on pavement and the company told me to send the board back and they would test it...cost me $53 to ship and they maintain nothing wrong with it. Lots of us are getting thrown off forward for some reason and the company seems to be stonewalling re: reason. I'm an old guy and I've been on crutches due to this.



  • @Kwok That's the answer...attach a couple of small wheels to the front to counter nose dive. I can bloody well do that. As soon as I get off my crutches I will give it a try.



  • @powder Just follow my advice (keep your center of gravity over the wheel, and concentrate on not putting your weight on the front footpad) and you should be fine. Even if you roll over something unexpected that causes the nose to suddenly go down, if you're balanced, you should be able to run it out instead of falling on your face.

    This isn't just something I made up... it's the physics of how the OneWheel works; plus it's how every advanced rider who never nosedives rides their OneWheel.



  • Thanks...will try harder to balance front to back. The times I nosed it were when I was trying to accelerate out of a dip in the pavement and I leaned forward when the board slowed too much.


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