INMOTION V11 (2020)

[Funky]

3 minutes ago, Chriull said:

Hardly, as the mosfets normal failure mode is short circuiting. So one would have to disconnect the malfunctioning board with something else than mosfets, as they could short circuit too in case of malfunction.

So it's not some algorithmic/random failure which 2 of three could decide, it's permanent failure of a board caused by "thermal design insuffciencies"==mosfet overburdening.

 

Fuses connecting both boards / 2 much power = disconnect xD (Sorry i have 15% knowledge in electronics) 

[jmsjms]

2 hours ago, meepmeepmayer said:

@jmsjms

...And even if it did and you had a fully "neutral" freely rotating tire, you would still fall...

I can't just balance myself till it decreases the speed to zero? That's horrible. I have been riding for one year and I didn't think of that. I assumed that it is just like a motorcycle engine shutting off -- the wheels still keep rolling.

Edited January 27, 2022 by jmsjms

[Paul A]

Don't need to carry a spare tire.......when you can carry a spare EUC! 

Think some people actually carry an EUC in a backpack, strapped on.

Not sure if it's a spare EUC or for when they are walking...

 

[meepmeepmayer]

Yep there are two boards. One "power" board with the MOSFETs, and this "control" board (I guess? or just auxiliary stuff?) on top.

I would like to add: I would trust a used board that has been confirmed working more than a new board that might (in theory) have a production issue.

Pictures by EcoDrift:

[Funky]

7 minutes ago, jmsjms said:

I can't just balance myself till it decreases the speed to zero? That's horrible. I have been riding for one year and I didn't think of that. I assumed that it is just like a motorcycle engine shutting off -- the wheels still keep rolling.

2 wheels = same as coasting on bicycle.. Euc dies, you face = ground.. Back of mind you have to be ready to kiss the ground. You wont be available to "run it off" also..

Same as someone would put stick in bicycle wheel.

Try standing on unpowered EUC = That most likely will happen at speed?

Edited January 27, 2022 by Funky

[meepmeepmayer]

10 minutes ago, jmsjms said:

I can't just balance myself till it decreases the speed to zero?

No chance.

You'll just fall, like suddenly everything is slippery ice.

There are various videos of people getting dumped by hoverboards. These are very weak, so overpowering them is a good analogy for them simply stopping working. It happens so fast. Nobody, even if they expect it, can balance that. Or just anybody slipping on slick ground or a rolling log or something that suddenly gives way.

I think the "slipping" analogy is a good mental model. Just try to stand on your wheel while it is off, and try to balance. You'll just slip, unless you are Superman. Now add yourself moving over uneven ground and not expecting it, with momentum and whatnot... no way!

The good news (I can't say that often enough), the chance of this happening with a normal wheel is extremely small. It's one of these quirks that EUCs have that are really annoying and even frustrating, but in reality it is not as big as an issue as the intuition tells.

Edited January 27, 2022 by meepmeepmayer

[jmsjms]

So, when the very first batch of EUCs (the ones produced ~5 y. ago or so) begin to die, there should be an increase of EUC crashes worldwide then. All EUCs will die one way or another... give it maximum of 5-10 years or so. It's something that the manufacturers didn't think when they started building the wheels!?

[Funky]

@jmsjms That's why it's better to buy fast EUC and ride at ~70-80% speed.. If you buy 31mph (50kmh)

Better ride at 25mph (40kmh)

Much, much safer... No overpower and such.

Edited January 27, 2022 by Funky

[meepmeepmayer]

No old models have "started dieing" yet. Not even the cheap noname clones right from the beginning. There's a good chance your battery will be dead and the wheel be beat up and crooked way before any perceptible number of boards start failing.

[jmsjms]

Hopefully some bright engineers are reading this thread right now, and thinking, Okay, if the manufacturers can't do it, then I'll figure it out. Maybe when you turn on the wheel, the wheel will know that it will shut off because the board will go bad, and it will go on safe mode: not allowing the rider to ride it, or allowing only 1-2 mph.

[Paul A]

welding-_-guru

 

· 1 yr. ago

I know a guy with 18,000 miles on a KS 18XL.

[meepmeepmayer]

25000km on an msuper V3 have also been achieved, for example. These had way weaker boards/smaller MOSFETs than we have now.

[Funky]

11 minutes ago, meepmeepmayer said:

25000km on an msuper V3 have also been achieved, for example. These had way weaker boards/smaller MOSFETs than we have now.

Same time any wheel can die suddenly at any given moment.. Even if that's 0.1% chance. Be riding at high speed. Or by burning down in my apartment. Kinda scary..

[Unventor]

34 minutes ago, Funky said:

Fuses connecting both boards / 2 much power = disconnect xD (Sorry i have 15% knowledge in electronics) 

Okey trying to make redundancy systems that can react fast enough is currently not possible. This has been discussed a lot of times here on the forum before. 

If I use another example. ABS brakes od a car system calculate wheel rotation vs lockups about 200 times pr seconds by looking at 4 wheels at the time. The response time is not as fast as it has to change the brake pressure on each wheel. 

If you had to determine something is wrong you need to both monitor, evaluate the react and then reevaluate again and still maintain balance. The time to do this simply takes too long (especially the react part). In the end other things you cannot do can go wrong too. Any mainfunctiin of the tire/tube/motor is a one item only that cannot be changed on the fly. 

Down to this, is why riding an self balancing device on one wheel is a trust game. The risk you take is there ALL THE TIME. It is why safe riding speed in any manual is listed as 20kmh as this is how fast most can run off or react to a problem without getting serious injury. Not all can do this, a few might be able to do it faster. 

You might be able to drive a car faster than speed limits are in a certain area or road, but the limit is a guidance to what can be handled safely both to the driver and their surroundings. And this is what most asking for faster speeds fail to consider. To be a balance between usefulness and risk and surroundings anticipation of the EUC riders there is a limit to this too. In most EU countries EUC are considered a similarity to a bicycle. It is not a MC for the above reasons. 

Now I don't ride a MC as I don't consider it safe for myself to do so. Fine for others. But we each have a risk limit we are prepared to take. Same as MC is not my game some will not ride an EUC for similar reasons. 

To talk redundancy for EUC really makes no sense to me. What we wish ifor is one thing don't it is a very different ballgame. So looking at high speed wheels these days they are 25kg+, adding double of everything or triple to have a reference point from weight alone would make the EUC an impossible product. 

Riding EUC is for some a sport others a commute others fun others away of making a living or exploring or alternative travel arrangements. But the risk is there at all time. Somethings can be done to lower the risks.

Redundancy is not one of these though. EUC riders need to be/come to terms with this. 

 

[Asphalt]

18 minutes ago, Unventor said:

Okey trying to make redundancy systems that can react fast enough is currently not possible.

Redundancy was implemented in the iPS S5 in 2018.

Dual motors, dual batteries, dual BMS, dual control boards.

[Tawpie]

54 minutes ago, Funky said:

Same time any wheel can die suddenly at any given moment.. Even if that's 0.1% chance. Be riding at high speed. Or by burning down in my apartment. Kinda scary..

It's why I don't take issue with non-riders that ask me if I'm crazy. I'm reckless enough to trust life and limb to consumer grade electronics trying to meet a price target, but there's no way you'll catch me skydiving. I mean, who in their right mind jumps out of a perfectly good airplane? I'm not crazy at all!

Edited January 28, 2022 by Tawpie

[Prisondude]

2 minutes ago, Tawpie said:

It's why I don't take issue with non-riders that ask me if I'm crazy. I'm reckless enough to trust life and limb to consumer grade electronics trying to meet a price target, but there's no way you'll catch me skydiving. I mean, who in their right mind jumps out of a perfectly good airplane? I'm not crazy at all!

i been thinking of skydiving looks like a fun adrenaline rush have done indoor version

[Paul A]

Plenty of skydiving/parachute accidents on YouTube.

 

 

[Unventor]

9 hours ago, Asphalt said:

Redundancy was implemented in the iPS S5 in 2018.

Dual motors, dual batteries, dual BMS, dual control boards.

I am pretty sure this model is not able to maintain balance on top speed/load performance. Also it didn't operate at the same speeds high end models do these days. 

[Chriull]

I'd wish at least one manufacturer would start to use state of the art design, manufacturing, QA and firmware!

As long as this is not the case redundancy is imho useless and counterproductive. What sense makes combining a couple of failing systems - they won't get better by this!

As long as one is far from maxing out the technical possibilities available with a single system there is no use in increasing complexity by redundancy.

And with EUCs there is no easy redundant system possible to overcome some faults...

[mrelwood]

14 hours ago, jmsjms said:

So, when the very first batch of EUCs (the ones produced ~5 y. ago or so)

First EUCs were made 10-12 years ago. I started riding 5 years ago. The one I bought 4.5 years ago is still in use as a spare wheel. The board is pretty much the only part of the wheel that hasn’t required any maintenance.

Electronics usually last a very long time. I have 16 year old electronics in my car, that has been stored outside in -20 - +30 •C temperatures year around, rain or shine.

 Guitarists often use electronics built 70 years ago, only replacing the wearing, easily replaceable parts.

 

14 hours ago, jmsjms said:

All EUCs will die one way or another... give it maximum of 5-10 years or so.

That’s the most pessimistic comment I’ve read in a long time! Why on earth would the controllers or anything else spontaneous fail so soon??

14 hours ago, jmsjms said:

It's something that the manufacturers didn't think when they started building the wheels!?

Since the wheels advance with such a blinding rate, a normal life cycle of an EUC is maybe 2-3 years, due to people wanting to buy newer features. Manufacturers are extremely well aware of this, as making mass produced items requires you to be able to reach the target group with a great precision.

Making EUCs that are designed to last 20 years would be just as aged in two years as the ones that cost a third, the cheaper ones just would’ve outsold the expensive ones a thousand times over.

13 hours ago, Asphalt said:

Redundancy was implemented in the iPS S5 in 2018.

Dual motors, dual batteries, dual BMS, dual control boards.

The wheel barely got released when IPS went under. That should speak in volumes. Redundancy is irrelevant if it only duplicates features that people don’t want to buy.

[RagingGrandpa]

22 hours ago, Asphalt said:

Redundancy was implemented in the iPS S5 in 2018.

Dual motors, dual batteries, dual BMS, dual control boards.

That redundancy did not increase safety.

If one motor fails, in the best-case you're left with only half of the normal amount of torque available, which means if the failure comes when you're riding 20mph, you'll instantly overlean and crash.

And worse, usually when one motor fails, it is because of an electrical fault that causes drag on the motor (or even causes the motor to lock up). So you've got one motor applying a braking force, and the other motor having to overcome it, plus keep the rider balanced. An impossible task.

Sadly, because of these failure modes, redundancy in the motor or the controller's power electronics does not make an EUC safer to ride at high speed. If a single FET fails, you're going down, even if you put 3 more FETs to back it up.  

(Redundancy of the battery pack is helpful though, and many modern EUC's like V11 and V12 do have the ability to run using 1/2 of the battery.)

[mike_bike_kite]

I quite like how Kingsong approached backup on their new S20. If the balance sensor fails for any reason then it can still sense position using other means. I know it's only one aspect of backup but it at least adds safety without adding extra risks. 

[mrelwood]

19 minutes ago, mike_bike_kite said:

I quite like how Kingsong approached backup on their new S20. If the balance sensor fails for any reason then it can still sense position using other means. I know it's only one aspect of backup but it at least adds safety without adding extra risks. 

I also applaud the gesture. I just don’t think I’ve read about a single EUC crash in the last 5 years caused by the hall sensors failing.

[fbhb]

40 minutes ago, mrelwood said:

I also applaud the gesture. I just don’t think I’ve read about a single EUC crash in the last 5 years caused by the hall sensors failing.

Didn't we just hear from Veteran claiming that the recent cut out issues with their Newly released Abrams were "Hall sensor" related?

Also, Denis Hagov posted a YouTube video where he had to replace the Hall sensors in his faulty Abrams (20.31 near the end):