Does the increased power/torque of the XR change nosedive likelihood?
Pretty simple question, though arriving at an answer may be hard. My very limited understanding of physics says more torque generally = faster acceleration. If I'm wrong on that, please correct me.
If many nosedives are caused by overaccelerating, outstripping the board's ability to both keep under you and keep its nose up; does additional acceleration and power help the board get back under the rider faster in this scenario, making the nosedive less likely?
Or, does the XR simply allow the inattentive, overaccelerating rider to reach the nosedive-danger tipping point in slightly less time off the starting line?
Or, is there no real change from the +?
It seems somewhat counterintuitive to think "more power = more safety", but I've actually been wondering for a while if more power would actually make the OneWheel slightly safer, by reducing (though never eliminating) the chances of a nosedive.
I've been thinking about this and in the grand scheme of things, more torque means more acceleration potentiality, but FM could also enlist a governing type of unit to help control speed/acceleration (not sure if this is known) so that more reserve power is in place to provide a noticeable/reliable kickback. I would think that's why there is no speed increase with the new version, just power/torque. 2HP is quite a bit of get up. Overacceleration nosedives will likely never go away though as there's no physical barrier stopping someone from pushing through kickback.
@ventoriffic Yeah, since the board doesn't actually have a 180-lb counterweight on the back, and isn't magic, I can ALWAYS force the nose down. But if it can somehow allow a slight bit more warning (when I nosedived mine, I felt no pushback - and I know what pushback feels like, and heed it) that would be a huge help. I know that nosedived can never be totally eliminated, but any enhancement to the board to make them more rare and harder to achieve would be welcome.
nosedives are (overwhelmingly) user error. Unless the user is going away with the XR, i'm not sure why people would think that would change.
@makermarc Sure. I repeatedly stated that I am fully aware nosedives cannot be eliminated, only (potentially) reduced.
If, as others have stated, nosedives are sometimes a case of overacceleration overloading the board's power capabilities (so it does not have enough juice to BOTH thrust/torque forward AND meaningfully pushback in case of overbalancing to the front) then at least in theory, changes to power allocation and acceleration/torque could make nosedives less (or more!) likely.
Again, no one has stated that nosedives can be eliminated. They can't, on a single-wheeled board. But it'd be nice if the margins could be widened.
I think it stands to reason that if the board has more power from the battery available, and can there for generate more torque, but doesn't increase the top speed. The chances of a ND should go down, just based on the possible # of scenario's the increased torque would make a difference in. The ND will never go away, but it "should" in theory decrease on the XR.
@glyph I think i understand the question, but it's completely relative. People who have smooth input and lots of experience riding don't have any nosedives whatsoever, so the extra power may benefit those people who can already feel the limits of the board. People who are not smooth and don't understand the limits will still likely face issues. It's possible the new battery pack has a slightly higher voltage, slightly higher max motor rpm, and can be pushed slightly further, but i'm not sure how this translates to fewer nosedives with leadfooted people that blow past the limits anyway.
It may very well increase the margin at lower speeds where the torque is still available, if that's what you're wondering. More than likely your second assumption is correct, people will just reach the point of no return faster.
@makermarc - I'll definitely be watching people's XR reviews and feedback here. I'd like it to be true only because I don't think of myself as a leadfoot, and after 256 largely uneventful miles on the + I nosedived for the first time and f*cked my arm/shoulder up bad, and I can't ride right now, and it SUCKS. I freaking love riding and can't wait to get back on, but am also gun-shy.
I am fully willing to accept it was probably my error (I was accelerating from a dead stop at a crosswalk) - maybe after 256 miles I got JUST comfortable enough to get cocky or careless.
But man, it'd be nice to think there's some combination of power-allocation/acceleration-governor/pushback and rebalance-trigger tradeoffs (and we know from riding modes that it's at least somewhat possible, since Delerium has more torque, and the board rebalances itself within smaller "lean" tolerances, than in Mission) that could have made this less likely.
Even better if these parameters were individually-cusomizable, so that I could say trade away a bit of aggressive performance for a bit of extra stability, while you could do the reverse trade.
Heal up soon brother! I think i remember reading about your injury.
I have mixed feelings about riding on pavement at the moment (and can't due to my studded tire). I don't even have that many miles on mine but I fall off continuously riding on snow/ice and it has changed my stance and helped my balance a ton. I run out every fall now without incident. There's no chill in my stance when i'm offroad, just constantly ready for the worst. Hopefully this translates over to pavement riding.
I remember how easy it was on pavement to just get into a groove and gradually trying to keep pushing that speed on a long stretches, standing nice and relaxed while riding. I feel for people just trying to get from A-B, that's likely when you need the pads the most.
@makermarc - my only prior bad spill was due to speeding too fast down a dark road I didn't know, and hitting a big bump that I didn't know was there at speed. Definitely a dumb error, but I got lucky that my equipment protected me.
I haven't been back to where my arm-breaking accident occurred, but I'd like to see the pavement there (it'll be one of my first destinations) - I was again riding at night and the road was not very familiar to me so even though I wasn't going (IMO) fast (as I said I was just coming off a dead stop), I do wonder if there was some uneven bit of pavement that overtaxed the board trying to rebalance itself while also accelerating, and/or caused me to bobble my stance and overweight the front of the board.
It all happened so fast, and afterwards I was too consumed with pain and trying to get myself and my gear out of the street and figure out how I was going to get myself home and to the ER, to do proper accident investigation.
One thing I've already done, is gotten a durable, bright, breakaway lighting rig to attach to the board, so when I'm riding at night the pavement around me should now be clearly lit. It wasn't cheap, but if it could have prevented this, it would have been a bargain. I'm also going to add a bicep pad to my leading arm, since in my experience if you can't run it out, that's probably where you're landing.
@glyph Long story kept long: Maybe, but most likely not noticeably enough. Digging into the future motions patents gives an insight on how the OW + vs V1 motors are built.
OW+ being about 2 pounds lighter, and having 5 Celcius better temperature performance at the same wattage, (simulations were done at 500W for both).
This increased temperature conductivity is probably how they pulled off using the same engine at 750 W instead of 500W, (remember that the V1 does have ~1500W momentary power, [ultimatley wattage is just how much Voltage and Amps you run through the motor]).
Anyway, getting back to the subject at hand. The improved thermal efficiency has probably been maxed out with the OW +, assuming all equal except the battery pack, we could see momentary increases in torque during cold starts, but as soon as the motor is up to temperature, I believe that will be the limiting factor.
The Battery chemistry is also different, NMC have a lower specific power than LiFeP04, but higher energy density. (Like running a small hose at high pressure, instead of a big hose at low pressure) On the other hand NMC (small hose high pressure, has a larger water tank. )
Issue 2: also by digging through the patents.
There are hints of the foot pads acting as an approximate weight sensor, which tunes torque(amps) feed to the users weight. This could give the rider a preliminary sense of confidence, as the board will compensate for a rider with more... em.. potential energy (weight) , but again, once the temps get maxed out, the board will save your investment from itself, and let you take the hit.
@drn3rd Actually, they don't need the footpad sensor data to estimate rider weight. That can all be done through monitoring the torque request vs. acceleration obtained. With all other things being the same, it's easy to make an estimate based on the energy being used.
I'm sure it is more difficult for the board to keep up with a heavy rider in high-torque situations, but ultimately, the board will reward the smoothest rider, not the lightest one.
@makermarc Agreed. I was just paraphrasing what the patents mention.
I would guess that, if the weight estimation is being used, it would be for something like a base value for torque requirements at start, i.e "motor engagement". But as patents go, these are mentioned in could's and if's.
@drn3rd Lots of interesting stuff in those patents!
Looks like they have official terminology describing how the pushback is calculated (based on the "power margin indicator")
@makermarc I love the way "pushback" et al, is describe in patent form.
Awesome, a patent with some actual information. I noticed poking around the OW+'s Bluetooth Low Energy API that it reports a live "Safety Headroom" value between 0-100. I'm working on a handsfree iOS app now to allow you to monitor that, battery, speed, foot sensor status etc. via an earbud and would really appreciate anybody who could help test. Send me a DM with your email and I'll add you to the beta group. Will announce more generally when it's a little more polished.
Or if you're a developer type, build it yourself here: https://github.com/OnlyInAmerica/OneWheelMonitor
@dbro Great idea!
I am interested however i haven't yet my new XR ;-)
I had received the OW + but it didn't work and, discovering this forum, I realized that the OW wasn't that safe as I had no idea about the "Nose dive" concept.
I hope your App' will also work with the XR
even at lower speeds, if people stomp too hard with a more powerful board (where software is enabling more torque) they will in some cases be MORE likely to nosedive due to wheelslip, depending on the terrain and rider weight.
@dbro Hey Dbro if you want to dig deeper
Is basically a collection of their patents