If you fell off EUC and got injured in the last few years, how are you all doing now?

[Keith]

1 hour ago, caelus said:

One option would be to deliver the max current - until max temp is reached. And only then cut out. Thus, you would have more time.
I never had a high speed cut out, so I don't know how it is behaving then.

Regarding the fall: as you are not hinged to the wheel you move on linearly. That is why even at very high speeds you usually have enough time to react before you hit the ground. The vertical velossity is independent of the horizontal speed.

I would expect that in a frontal fall (faceplant) you are better off without helmet (if that doesn't have a full face guard).
 

Actually I don't think so. In offroad situations, you allways might hit some stone or a tree, thats where a helmet can come in benefical. Otherwise it is not! If there is no obstacle, you usually only have to deal with abrasion. And 30km/h is not fast by any means if you just land on the tarmac. But all that is very individual and depends on how you are used to falling from speed.

What IS that strange smell? Ah, I've got it.......... bullshit! 4 paragraphs absolutely full of it.

at least if you have now bought a Gotway V3, maybe you can shut up until you actually have some experience of "moving on linearly" when the wheel fails and "having nothing except abrasions to deal with at 30 km/h.

As @KingSong69 has said above you do not have a clue about how an EUC works and what it's motor has to do to keep you balancing- despite it being explained ad nauseum in this forum.

Edited September 4, 2017 by Keith

[Scatcat]

Now now boys, no need to get angry...  

The cut-out happens because the alternative are burning batteries or blown circuits. There is no such thing as "max power - until max temp is reached", because there are set limits on the power the batteries will provide, and the power the board and cabling can take.

You don't want a battery fire.

You REALLY don't want a battery fire.

And if you overstress the board, the only thing that blown circuits will give you are maybe a tenth of a second more to react. OTOH if you fall and manage to roll out of it, you now have a burned out EUC to limpingly lift home. Probably with fused wires, blown MOS and locked wheel.

Cut-out crashes will be part of the story for as long as the power and redundancy of the EUCs are less than the craziest of us riders demand of them. When we have carbon-carbon batteries or somesuch, that can deliver twice the power without heating up; when we have redundant circuits; when motor-power are twice what they have now AND when the manufacturers over-engineer their wheels with two grades thicker cabling and perfect QC - then maybe.

And by the way. Look at some videos of people suffering cut-outs. You will note that in effect the wheel acts as a hinge. If you are sharp and have the right stance, you may be able to push upward forward in the fall and gain more leverage for the tuck and roll. But then again, unless you know what's happening, the reflex is trying to regain your balance.

[HermanTheGerman]

9 hours ago, caelus said:

I never had a high speed cut out, so I don't know how it is behaving then.

Yes, you can't on an airwheel.  It's no big deal to run off any problem in most cases, also on the old Ninebots.

 

9 hours ago, caelus said:

Regarding the fall: as you are not hinged to the wheel you move on linearly. That is why even at very high speeds you usually have enough time to react before you hit the ground. The vertical velossity is independent of the horizontal speed.

Sure. 

But now lets put aside your old airwheel, and take a look at your new old MCM V3, a wheel with 260Wh battery being able to run 28 km/h (but not much more, which is bad, because it means it has no power and torque to spare).

This is the right wheel to learn what a cutout and a faceplant at higher speed is, so actually I wouldn't need to describe it, but I'll do:

You ride at the wheel's limit around 28 km/h,  battery is already around 50%, wheel hits a small hole, cannot manage it and cuts out. Your body position was quite forward leaning to keep the speed, and the rubber of your shoes has enough friction to keep you connected for a fraction of a second, while the wheel tilts forward to throw you off. This reduces the speed of your feet, while head and chest try to keep the existing pace because of their physical inertia. Before you have time to think, your feet will touch ground, which further reduces their speed, and now you act as a pendulum:

Your feet, grabbing the ground like an anchor, accelerate your body and head into a circular motion where the head gets the most acceleration, and whAmm, your nose made of steel carves a sharp scratch into the street.  If you are very fast, you may turn your head before, so that the side part of your (hopefully) helmet hits the street, instead of the front. 

 

9 hours ago, caelus said:

And 30km/h is not fast by any means if you just land on the tarmac. But all that is very individual and depends on how you are used to falling from speed.

Good luck.

I'm writing this as one guy who learned the hard way that it is better to wear a helmet when skiing, cycling or motor cycling. From my point of view the pseudo scientific article at your given link, which describes that wearing a helmet is more dangerous than not wearing one, is just crap.

Edited September 4, 2017 by HermanTheGerman
take/put wording

[Scatcat]

Just to get an idea of what a downhill helmet with a chin guard can do for you, look at this testing video for Bell Super MIPS 2R... Especially at 1:45 and forward, where they simulate a true fall.

 

Edited September 4, 2017 by Scatcat

[WARPed1701D]

2 hours ago, Scatcat said:

Just to get an idea of what a downhill helmet with a chin guard can do for you, look at this testing video for Bell Super MIPS 2R... Especially at 1:45 and forward, where they simulate a true fall.

 

And that helmet isn't actually downhill rated.

Look at this video of the Met Parachute that is rated. I'm sure you see less deformation of the bar during impact.

 

[radial]

Maybe I misunderstand the meaning of the term, but I don't see how the construction of the Parachute helmet really qualifies as "monocoque."  According to the video, the chin guard and helmet shell are two separate pieces fastened together at four points.  I'm sure those fasteners are very sturdy, but two-piece construction isn't monocoque in my book. It looks like a very nice helmet, though.  I would wear it without hesitation.  

[Scatcat]

3 hours ago, WARPed1701D said:

And that helmet isn't actually downhill rated.

Look at this video of the Met Parachute that is rated. I'm sure you see less deformation of the bar during impact.

 

As I understand it, the DH-rating of the Bell 2R only fails on the sides, where the ventilation holes are judged to allow a branch or other pointy debris to poke through. Also the geometry apparently leaves a bit more of the side of the face vulnerable to poking damage.

The strength of the chin guard per see, is supposed to meet the standards. And you can see in the respective videos that neither chin-guard allows flex enough to actually hit the face in the tests.

I ordered the Bell, mostly because I want to be able to remove the bar when I feel I don't need it. I'll get back with my own judgement of it when I have some personal experience.

[Mono]

On 03/09/2017 at 7:47 PM, Scatcat said:

Let's put this in simple terms @caelus.

Do you think my acquaintance, the swede with the titanium inserts, would be alive today without his helmet?

He went full body slam, and you can read the litania of injuries he suffered above. No evasions, no statistical speculations, no "he might not have had that accident if..." - just your honest judgement if he would still be with us.

Given the description of the accident and injury pattern, I would say the helmet probably didn't help in this scenario (no way to say with any reasonable certainty, of course). There is even some (maybe small) chance the helmet aggravated the injury, because it added mass to the face which planted into the ground. 

It's not the first case where I have read of a serious injury despite recommended protection gear in this forum. I find it puzzling that the overwhelming reflex is, even in these cases, to talk about...how protection gear is important to prevent injuries. Kind of funny, if it wouldn't be such a serious matter. There are quite likely at least a couple of much more important factors which could have improved the situation in this accident and in many others. Just for some reason, nobody dares to talk about them in the context of an accident with serious injuries. The big elephant in the room.

Edited September 4, 2017 by Mono

[Scatcat]

30 minutes ago, Mono said:

Given the description of the accident and injury pattern, I would say the helmet probably didn't help in this scenario. There is even some (maybe small) chance the helmet aggravated the injury, because it added mass to the face which planted into the ground. 

It's not the first case where I have read of a serious injury despite recommended protection gear in this forum. I find it puzzling that the overwhelming reflex is, even in these cases, to talk about...how protection gear is important to prevent injuries. Kind of funny, if it wouldn't be such a serious matter. There are quite likely at least a couple of much more important factors which would have improved the situation in this accident and in many others. Just for some reason, nobody dares to talk about them. The big elephant in the room.

I'd say that the fact that the helmet became scrap plastic, and his forehead/frontal lobe didn't, points to the helmet actually helping him keep breathing and thinking straight.

But yes, protection is not the only factor.

Speed is one important factor. Reserve torque is another very important factor. The fact that most of us are "old men" with about as much athleticism as Garfield is certainly a factor. I could go on, but there it is.

The wheels we ride go faster than they're truly capable of. In another thread me and @meepmeepmayer joked around about what we would design into a EUC. But it was only half a joke, because while we oh, and ah about the latest and greatest, all the wheels on the market are really insufficient.

They are, as was said in another discussion, comparable to early airplanes. Fantastic in their innovation, but death traps compared to even a current light-weight.

We have too little max-power, and too slanted a torque curve compared to the max-speeds. We could well use 4kW motors rather than the current 800W-2kW ones. We could use batteries that could deliver twice the voltage and twice the amperage, with wires/circuits and boards to match. We could use full redundancy. We could use a lot flatter battery curves, that can deliver safe power even when the battery falls below 50%. Wider tyres, one piece pedal arms, thicker shafts, watertight internals, speed-limits that leaves 15-25% headroom in the torque department and so on. If you go down a pot-hole, there should be enough power to climb back up. Maybe a scary jump at the end, but no cut-out.

And then of course it comes down to our own behaviour...

I routinely run my GT16 at 20mph for long stretches, sometimes even a bit more. Sure it has a 2kW motor, but still it has no redundancy and only a 16" x 2.125" wheel. Even a gust of wind is enough to force me to compensate by using my body angle to catch and deflect the airflow. A simple bump I don't see is enough to rattle my teeth, and that is even though I never ride with straight legs, never ever. A patch of wet mud in the wrong place can make me skid and almost lose my balance. Just in the last week, I've had two close calls with fate. One a f-ing bicyclist that went like a moron in the wrong lane at a red light and the other a Beamer with racing ambitions coming into a roundabout. In both cases I was fractions of a second away from something very serious indeed. In the case of the bike I ended up going up a curb and almost getting stuck on it. In the case of the BMW only a panic power break and a swerve kept me from becoming the bambi on his bumper.

So no, protection is not everything. It's just the bloody insurance policy when all else goes to hell. We hope the insurance is good enough, but we won't know until we actually need it.

Edited September 4, 2017 by Scatcat

[Mono]

You are talking to a large extend about factors we cannot control now or even in future and that won't have any impact on our safety right now or in near future. Maybe it gives some ease of mind, but it's IMHO not the best time investment on safety return.

Edited September 4, 2017 by Mono

[Stan Onymous]

6 hours ago, radial said:

 I'm sure those fasteners are very sturdy, but two-piece construction isn't monocoque in my book.

Monocoque refers to the body is the frame. So the Dodge darts in the 60-70 that made the design popular in America are made up of several panels spot welded at their seams. Same thing for the Subaru 360. What I think you are describing is forged, but that would ofcourse be too heavy. The planes that were also monocoque were called this not because they were one piece, but because the body of the plane was the support in order to save weight. That is my remedial knowledge of monocoque design in cars.

[caelus]

On 4.9.2017 at 11:23 AM, KingSong69 said:

the GW V3....absolutly unknown to such things like cut-outs because of

- batterie fail,  mosfet burn, shorted connector, burned wires,  blown dc converters etc etc

[ironic mode off]

 

Cut-outs dont go away from "knowledge"...they can only be prevent by redundancy, which no EUC has until today. 

A cut out is scary, but - hopefully - rather unlikely. Anyway, it would help a lot to exactly know in which cases a cut out may occure. I tried to search in the forum, but unfortunately there seems to be no clear answer. I searched youtube, and I found two cut out crashes. The one because of "oszillations" - could be solved by firmware update. And this one, considered to be a speed cut out on a descend. I don't know it it really was a cut out. But don't see, why the software should do a cut out in this case. All other crashes I found where not related to cut out (overlean, etc). Any other experiences here, where a cut out occured?

On 4.9.2017 at 9:57 AM, Scatcat said:

Rather immediately you hit the maximum power available and when that is not sufficient the wheel cuts out. Either because a MOS blows, or because the circuit turns off to protect itself from burnout.

The wheels do support peaks of very high load and don't cut out "rather immediately". Probably they cut out if certain temp is reached - but that takes some time of high load.

Anybody knows the exact algorithm behind? Coul'd find it searching.

[Scatcat]

3 hours ago, caelus said:

A cut out is scary, but - hopefully - rather unlikely. Anyway, it would help a lot to exactly know in which cases a cut out may occure. I tried to search in the forum, but unfortunately there seems to be no clear answer. I searched youtube, and I found two cut out crashes. The one because of "oszillations" - could be solved by firmware update. And this one, considered to be a speed cut out on a descend. I don't know it it really was a cut out. But don't see, why the software should do a cut out in this case. All other crashes I found where not related to cut out (overlean, etc). Any other experiences here, where a cut out occured?

The wheels do support peaks of very high load and don't cut out "rather immediately". Probably they cut out if certain temp is reached - but that takes some time of high load.

Anybody knows the exact algorithm behind? Coul'd find it searching.

Nomad's fall isn't very informative, since the camera tumbled too.

He had a lot of luck, more than his fair share actually. He got off with only minor cuts and bruises. I run the exact same stretch of road at the end of his video about three to four times a week, and there are no obstacles at all. So as long as you don't crash into a pedestrian or bicyclist there is just super-smooth asphalt worn down by years of light traffic use.

Still, he was going 45kmh, which is a little bit faster than the human body was meant to run or handle.

As I understand it, when you get a clean over-speeding cut-out without any obstacles, the wheel often goes "squishy", for lack of a better term. That is, you get a few eye-blinks where you feel the wheel losing its stability before actually falling. I've heard recollections of Nomad's fall from people who have "discussed" his risk-taking with him, and from what I've heard that was the only warning he got. Still, it was enough for him to start a run-off. He of course fell and hit his hands on the wrist guard skid-surface but managed to convert it to a roll. You sometimes see such unclean rolls out of over-speeding cut-outs. There are a few more examples of cut-offs on youtube, like:

In the first video you see a sort-of-tuck-n-roll, in the second not so much. The guy in the first video knew he could very well take a fall, and prepared for it. Still stupid, but not totally moronic.

Imagine the second fall without protective gear. Not only do you hit the asphalt at 50kmh: Denim keeps abrasions from your skin for about 20cm of the glide. Your head is at risk not only from the ground, but from the EUC coming up behind you.

Now suppose you have knee-padding, then you glide on that instead of your skin. Same for elbow-padding. If you have good wrist protection, the impact force doesn't hit the fine bones in your hand and wrist, but part of the force moves upward along the arm. And if you have a good helmet - then at least the straight impacts as you bounce, and the impact from your EUC if you're unlucky enough to have it hit the back of your head won't play spoon and egg with your cranium.

This guy in the second video wen't like a moron, but at least he was protected.

Edited September 6, 2017 by Scatcat

[Stan Onymous]

It has been talked about several times on the forum and in several threads. In my posts it was fewer cells and faulty cells inside the battery that cause my shutdown. 

The battery shutoff problem is a power issue due to high speeds needing high watts. When your battery goes down to 35%, you are no longer carrying 67v. It may be more like 61v, and that will tax the amps to ramp up. At a certain amperage, the wires become overheated and start resistance which can lead to shut down. Also having battery packs with fewer cells will exacerbate this problem. I am not aware of their algorythms, and they may be trade secrets so dont hold your breath. 

That is essentially the problem with all DC transmission. Heat and resistance. It is also the reason why most newer EUCs govern the speed as the battery depletes.

Edited September 6, 2017 by Stan Onymous

[US69]

3 hours ago, caelus said:

The wheels do support peaks of very high load and don't cut out "rather immediately". Probably they cut out if certain temp is reached - but that takes some time of high load.

Could you please forget your "cutout attempts on high temps" thoughts? thats nonsens, sorry!

A cutOut happens when something in the wheel fails.....that can be all: one of the 120 batterie cells, a little conductor on the board, a wire, a fuse etc etc etc

Mostly it is a fail because of mosfets! mosfets on first place! And: They are not that seldom!!! 

Has nothing to do with temperature, on high temp you get a high temp warning beep and tiltback, thats it...than you have enough time to slow down!

 

Also on ALL wheels a cutout happens when you go over the MAXIMUM speed the wheel is capable, that lies in the nature of self balancing vehicles...to explain that, would take about an article of writing!

 To make it short: if you reached the barrier of your wheel-the max speed- NO EUC in the world is able to "just slow you down"!!!

As long as you push IT HAS TO try to get faster...and that fails on a certain point, and the wheel cutsout.....

 

Dont get me wrong: Thats really not meant as offense, but with your airwheel AND reduced technical experience, most here are a "bit offensed" when they hear that a helmet is useless and in the same sentence get that your technical understanding is a bit underdeveloped....

From own experience...i have broken 4-5 rips on my 2 main falls, and was only lucky that my head didnt hit a sidewalk or something, i wouldnt be here anymore.  So a VERY friendly and neat advise would be just to read a bit more in the forums here, about falls, cutouts....technical failures (especially on the GW V3, as we are all beta testers for some Gotway devices)....

And get a bit more informed :-)

Then the "wind against" your statements would not be so hefty!

Edited September 6, 2017 by KingSong69

[Scatcat]

Actually, let me try a very simple explanation of cut-outs at high speed.

1. When a electric motor spins, it generates electricity. That is the reason we have regenerative breaking. The higher the speed the higher the voltage. And the voltage is polar reversed to what we feed the motor with.
2. So the voltage we send to the motor must be higher than the voltage the motor generates, or we would have zero power.
3. As the speed go up, the voltage to overcome gets higher, and the potential difference lower. The effect is a negative torque curve, where the torque eventually reaches zero.
4. The absolute max speed is the cut-off speed with the wheel in the air. Usually 30-40% higher than the practical max speed with a 70kg rider on the ground.
5. When you reach beyond practical max-speed, the remaining torque is very close to zero, there is no power left to balance the wheel. A piece of gravel, a small crack in the road or just moving your hands forward may be the tipping point where the pedals start dipping forward. There is now no way in hell you can recover.
6. One of two things happen. 
   • a: The wheel goes squishy, since it can no longer up the power as needed and you're better off jumping off even if you're going 50kph, or
   • b: The wheel tries to compensate, even though it can't and something fails - a BMS, a MOS, a melting cable, a connector, a soldering, a fuse.
7. If a happens you have a slim chance to tuck and roll, if b happens you're face-planting.

[caelus]

3 hours ago, Scatcat said:

There are a few more examples of cut-offs on youtube, like:

These are both not cut offs.
It's just overlean at high speed, where the motor hasn't enough torque. But it did not cut off. It's the same as in this crash.

[novazeus]

7 minutes ago, caelus said:

These are both not cut offs.
It's just overlean at high speed, where the motor hasn't enough torque. But it did not cut off. It's the same as in this crash.

x-games can't be too far off after watching this guy's video. x-games would be safer, no pine trees.

[steve454]

@caelus  here is one.  Also go to Youtube and read the comments, very interesting.

 

Edited September 6, 2017 by steve454

[steve454]

@caelus  this one he gives a good explanation as to what will happen if you exceed the max speed.  He has no protection but still rides to the point where the wheel starts to feel mushy.

[caelus]

55 minutes ago, steve454 said:

@caelus  here is one.  Also go to Youtube and read the comments, very interesting.

Thanks for the Video. This one seems to be a firmware problem, see comment by Daniel Orantes: "Apparently they put out a bad firmware update (1.26) that caused random shutoffs and threw their riders. That being said I still purchased a Ninebot One E+ and have enjoyed it for a week now with no incidents (using firmware 1.27). Also Ninebot does not just shutoff when you exceed max speed / power limitations, it deflects the pedals and slows you down."

[caelus]

48 minutes ago, steve454 said:

@caelus  this one he gives a good explanation as to what will happen if you exceed the max speed.  He has no protection but still rides to the point where the wheel starts to feel mushy.

He is also talking about loosing torque, not a cut off.

Unless you are going on a descend, it should be impossible to reach the cut-off speed. You can only get there by lift test, i.e., without load.

[steve454]

4 minutes ago, caelus said:

Thanks for the Video. This one seems to be a firmware problem, see comment by Daniel Orantes: "Apparently they put out a bad firmware update (1.26) that caused random shutoffs and threw their riders. That being said I still purchased a Ninebot One E+ and have enjoyed it for a week now with no incidents (using firmware 1.27). Also Ninebot does not just shutoff when you exceed max speed / power limitations, it deflects the pedals and slows you down."

Your welcome.  As far as I recall, I haven't seen any real cutoff videos seen from the side, only overleans.  The few cutoff videos are hard to see what exactly it is like, just one second the rider is riding, then instantly the camera and rider go down.

[caelus]

What kind of habit is that to give negative rep on each post??

[kasenutty]

Do you not like it? I gave you a negative, and I will explain: I did not like what you said. 

 

If you don't like what I say, give me a negative back. 

Edited September 7, 2017 by kasenutty