Would you rather an EUC that is safe for the rider or to protect itself?

[Murdomeek]

I see this topic pop up again and again and I'm curious on where everyone stands.

- Would you rather an EUC that provides maximum safety to the rider by always trying to keep them balanced no matter what?  By continuously giving maximum power in those situations until it self destructs?  (Max speed and hits a bump, going up a steep trail and over torques it, etc).  The most likely component is the mosfets in the controller that would die.

- Or would you rather an EUC that protects itself in the event of a max load situation?  Via firmware safety limits, current limits, fuses, etc.  A controller replacement costs $200-$500, weeks of shipping, technical skill labor involved, more wait time if you get a shop to do it, etc, etc.  You can miss entire months of summer riding season depending on where you are.  You would rather get dumped than have to deal with the headache of getting a controller replacement repair job done.  


Over the years, I've seen both sides of the argument:

- WTF my $3000 EUC died from an over torque going 5kph!

- WTF my EUC just dumped me going over a bump on the street! Screw the wheel, I could have been hit by a car and died!

- We need more built in safety features to protect the components. Vote for quality!

- I want all the unrestricted, unlimited power I can get ripping race tracks or climbing mountains as a 300lb heavyweight rider. I know the limits, I can play within it. 

- etc, etc, etc

Obviously the answers depend on the rider and the type of riding they do. Also their beliefs on personal safety vs the monetary and time costs of a controller replacement.  Hence the poll

*These max load situations I'm talking about are beyond the standard beeps and tiltback and app warnings safetys.  Either the user ignores them, cant hear, is ignorant, or the power draw is too fast for them to react.  

 

Curious to see what you guys think

 

[Punxatawneyjoe]

In my opinion, you could have all the safety's in the world. Beeper, 200 db siren, tilt back a wire stuck up your.....well you get the idea. And someone is always going to ignore/break or push it beyond it's limits just to get twidiot likes. Also i think I'm slightly confused about the 2 options you have here because wouldn't a dead controller result in a cut out?

[Murdomeek]

Yes, but their argument is I'd rather have ALL the power, in case the extra few amps will save my fall/ buy more time for me to react.  

[Robse]

I really don't see the point.  Either situation ends with a cutout sooner or later. The user is responsible 99% of times.  If there is no cutout, the cutout will happen anyway, just 10 ms later when no power is left, so whats the point?  Have a cutout and no fried electronics,  or have a cutout AND fried electronics?  Vote here  [  ]:yes   [  ]:Yes

[Cerbera]

The wheel should save itself, and cut out and drop you if it's between that and frying the motherboard AS WELL. Nothing worse than horribly injuring yourself or just being shaken up after a crash, only to find yourself stuck in the middle of nowhere with a non-functional wheel that can't get you home, and will seriously burden your attempts to try and get there under your own steam...

Edited February 17, 2023 by Cerbera

[Robse]

2 minutes ago, Cerbera said:

The wheel should save itself, and cut out and drop you if it's between that and frying the motherboard AS WELL. Nothing worse than horribly injuring yourself in a crash only to find yourself struck in the middle of nowhere with a non functional wheel that can't get you home. At least if it saved itself there some chance it'll still get you home !

that's a good point 🙂 did not think of that "option"  However: (my opinion) people should not ride in the middle of nowhere without some sort of backup: phone, partner, "if I'm not at home at 5 do call" etc

[Cerbera]

1 hour ago, Robse said:

However: (my opinion) people should not ride in the middle of nowhere without some sort of backup: phone, partner, "if I'm not at home at 5 do call" etc

Your phone can sometimes break in the same crash you need it to solve, or if you are out in the wilderness or up a mountain, you can find yourself with none reception and a very long way from the nearest taxi-accessible road ! @Marty Backe , renowned exemplar of EUC massive trip best practices, always primes the Mrs with where he'll be and when, and takes a backup GPS device with him, which is all good advice, but in my case there's only the cat to tell, and she has a record of being particularly shit at rescue coordination ! So I tend to plan any off-roading I do so it's not too far off-road !

 

Edited February 17, 2023 by Cerbera

[meepmeepmayer]

I voted for "dead controller" because I don't trust the manufacturers to implement limits properly. It's probably less likely to fry a board than some part of a limit failing - like a too-weak fuse or a wheel that dumps you too early just to be safe - so what seems safer might be less safe. I'd rather have as few extra parts as possible which I need to trust to work properly.

Also, hardware frying should not really happen spontaneously. It's from prolonged extreme stress. So you can have some temperature warning if you have the right sensors, which give you a few seconds for the wheel to warn you.

Looking at the latest fried Master Pro, forcing it uphill, the motor fried (wow!) before the board. So you can have beautifully strong mosfets/boards (credit to Begode where credit is due) and, if you add temperature sensors in the right places (motor), hopefully a bit of a warning time for overheating problems. These "My wheel hit a tiny bump and died on the spot" reports tend to be from wheels with too-weak mosfets/boards in the first place, something that is easily fixable.

Give me reliable hardware instead of mitigating mediocre hardware with mediocre workarounds for supposed safety (not so sure about that).

Maybe it's not as black and white, and some safety limits make very much sense and can be implemented safely and reliably. But in doubt I'd choose to keep everything simple.

[dycus]

I think the wheel should always protect itself. This is also a critical safety feature - letting the control board fry itself can easily result in huge currents being drawn from the battery, either due to a short or low resistance from charred PCB. If the battery is also "cutout resistant" (fused too high or not at all, too high current limit implemented, etc), you could have a battery fire on your hands. This is the absolute worst case scenario with an EUC, in my opinion.

[Funky]

Don't ride at the limits of the wheel.. And you won't need any of these options.

Rider is responsible for his/her ass. Or in this case face. 

 

Option 1 wheel keeps the rider extra ~1-5 seconds upright. But ending is the same faceplant.. + Dead wheel. (Maybe fire.)

Option 2 wheel cuts out faster. But same time doesn't self-destruct.

 

I will go option 2 - simply because i'm not riding at the limits of mine wheel. And i respect the beeps/alarms. 

Option 1 is for those "reckless morons". Who ignore beeps and keep on trucking.

Edited February 17, 2023 by Funky

[alcatraz]

It's a tricky subject. Ideally we need abundant power so the question be made moot. Since we're not at that point yet... 

I'd rather risk blowing the wheel than landing needlessly on my ass, for hitting a pothole accidentally or whatever spiking the wheel and triggering a safety circuit.

I had a failure once, and at that time I would have liked to have a master switch to turn off the batteries' connection to the board. Instead I had to roll the wheel back home, not knowing if the packs were shorting out or not. Not knowing if the smell came from the board or the packs. That was scary.

So to conclude. Vote yes to blow the wheel, but with a heavy duty master switch somewhere.

[RagingGrandpa]

On 2/17/2023 at 2:05 PM, Murdomeek said:

Would you rather?

1) Early cutout
2) Dead controller

That is misleading. 
People can easily interpret that as a choice between 1) Crashing, and 2) Not crashing but damaging electronics. That's wrong! 

Instead of 'cut-out,' Option 1 really means 'performance limits' by means of permanently-enabled tiltback (e.g.: Inmotion EUC's), or motor current limiting (like all EUC's have). 
Limiting performance does not mean a crash. 

'Dead controller' guarantees a crash! 

So in reality, it's like this:
Option 1 is Limiting performance, 
Option 2 is Crashing because of electronics damage. 

Crashing is physically traumatic, so if the choices are only these two, I think all rational adults must choose #1.
 

And as @meepmeepmayer mentioned, the devil is in the details: if performance limits are set with stupidly low or stupidly high values, it's bad for us. Meaning: we're not getting the speeds and torques that the expensive machine could otherwise do (e.g. 18XL 29mph tiltback); or that the limits are set so high that you'll burn boards before the human has time to react (e.g. MSX temperature alarm). 

It's always been this way: a good EUC must have very carefully chosen performance limits. Some models get it right; others don't. 
 

The message I take-away from your poll is: "What would customers prefer: reduced-performance lower-risk riding, or max-performance high-risk riding?" 
But the way you're presenting it hides the message too deeply, so I think we won't get the real answer from this poll result.

Good to encourage discussion on it though!
 

Edited February 24, 2023 by RagingGrandpa

[Tawpie]

I mostly ride wheels that I'm pretty sure are in the early cutout category, and it at times it most certainly is annoying. But (knock on wood) I haven't had to walk anything out of the woods (yet).

Hidden under the max-performance high-risk riding equation is something beyond "not blowing the motor drivers", and that is something I think should be mandatory: do not overstress the batteries.

Manufacturers are pretty good about not allowing overstress with the possible (not proven) exception of the GW 900 Wh packs. The working theory on those is that the wheel's controller allowed routine overstress of the battery and that resulted in well understood progressive damage to the cells themselves. It's supposition to extend the (possible) damage as having caused the fires, but for the cautious, where there's smoke, there's fire. eWheels spent a great deal of money replacing batteries because of this theory, and continues to distrust even the early cutout manufacturer's commitment to ensuring the batteries are not used outside their safe operating envelope.

So, when you setup the firmware to protect the system, don't forget to protect the batteries or you may be laying the groundwork for a fire and that has the potential to affect much more than the life of the rider. This is why I'm an early cutout rider—if I stay farther from overlean, there's a good chance I'm also farther away from wounding my battery. Maybe not in fact, but "probably"! (hopefully)

Edited February 24, 2023 by Tawpie

[Paul A]

Maybe just wear an airbag vest and have the cutout early.

 

On 2/18/2023 at 8:31 AM, Cerbera said:

backup GPS device

Yes, for off roading, especially solo riding.

Personal locator beacons are cheap, compact, reliable, 5-10 years battery life.

[alcatraz]

Some risk of injury can be mitigated with performance limits, but it also adds risk, a controversial subject. As long as it reduces more risk than it adds, it's a net benefit. Is it for every rider though?

Crashes are always going to happen more on wheels without limits because that's the (on average) preferred wheel of speed freaks etc.

[alcatraz]

I lean towards warnings needing a major upgrade. Something that can't be missed by the rider regardless of situation. Loud wind noise etc. 

Together with a proper warning system, then allowing the wheel to self destruct would (in my mind) provide the least possible risk of injury.

[mrelwood]

Great points in the comments!

 This does make me think of a commuter car vs a race car. A race car isn’t supposed to last long, and every bit of added power are taken advantage of. It’s normal to replace the parts often.

A commuter car on the other hand has very different priorities, and lasting long is a key feature. Performance doesn’t need to be at the bleeding edge.

 The comparison isn’t dead on, since a self-balancing vehicle has a high cost of component failure in form of a crash. But there are similarities.

 I’m sure that Roger and other racers rather replace the board than be limited in any way, but in general, for every other kind of riding a reasonably well adjusted limiter clearly makes the most sense. But the limiter doesn’t act on it’s own, there are always alarms and tilt-back in place that try their best to prevent the rider ever reaching the limiter. And this makes the question a bit misleading. It’s not about a limiter crash vs non-limiter survival, but a slightly earlier alert vs a non-limiter crash later on.