The wheel that broke Marty’s Leg
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- čas přidán 9. 09. 2024
- In this video, I do an examination of the wheel that failed while Marty was riding it and ended up causing two broken bones in his leg.
Marty is in good spirits and I think he will be back on his wheel before solid-state batteries are a thing.
Great video Roger and you are insane for riding it at the end, although it made me laugh.
I really don’t want it back so if you can think of anything to do with it, feel free 🙂
Hey Marty, wishing you a speedy and complete recovery!
feel better marty, sorry to hear about this, you are a tank, get well soon
You have a hole in ya shirt lol
Marty, if you dont want it back, and roger has given it the A-ok on a health check, why don't you raffle the wheel off and the money could help pay someones hospital bill who doesn't have insurance or give it to someone who lost their wheel in a bad accident.
Get well soon Marty Backeman!
Get the log file from EUC world from Marty's phone. Also take the motor apart and check if the hall sensor board is kinda loose and can wiggle over bumps. Check if the solder points might have scraped the inside of the motor cover and did a temporary short. If there is no silicone or anything on the solder points, put some on to prevent further cutouts.
You guys should continue to use this machine to see if it repeats the issue. This is already the most famous EUC! keep it alive.
Roger, thanks for the teardown. As yet another engineer it seems we're left with Single Event Upset (SEU) as the most likely cause. SEU, is why aircraft controls are usually triplex, quad, or dual redundant. And note that EUC redundancy is inherently limited by single 3 phase motors. Redundant hall sensors do make good sense as well as possibly dual/dual battery and controller designs (as well as the multi-transistors). Maybe someday we'll even be using 6 phase motors (don't hold your breath, that will be years if ever).
Of course, you write everything well and correctly about redundancy, but in the Begode A2, the power supply of the processor and peripherals is served by one chain of DC-DC converters, and previously it was different. Now any failure/short circuit in the periphery will cause an overload on the power system and lead to a reboot of the controller processor. This is a blatant disgrace. It was done well on the first mten4 controllers
@@MrIbif IDK the specifics of the A2 design. My point is more about redundant systems being necessary for life-safety. Single engine airplanes get to be simplex with "fail safe". Simplex maybe "fail safe" depending upon the FMECA (can glide to the ground), but in the case of a simplex controller-battery-motor needed for safety, how? I mean no dead code, sure - or maybe DO178? But without hardware redundancy its all bullshit. CMMI says miles without unexpected software failure shows flight safety, but such simplex systems only achieve 10^-3 level mission reliability. Why? Well SEU (muons, space particles upset bits in memory/computer). Only redundant control systems overcome that. I've been working redundant systems like that with avionics/engines since the mid 1980s. These wheels are risky, even with perfect hardware. SEU is real. 6 phase, dual/dual control/power - I'd pay $10K for the equivalent performance of a Master with that (and add 20lbs w/o performance boost too). My other POV issue is swappable batteries for less weight configuration with high range config-options and charged swap range extensions w/o base weight being bloated beyond my use cases.
I don't think people realize how rare SEU are and what kind of precise bit flipping is required to get specific output.
“Marty is on a lot of drugs, he’s been hanging out with the Knight Riders too much.” 🤣☠️🤣☠️🤣☠️
I have the issue with cheap Airwheel, that the wheel doesn't stop spinning when footrests hit the ground therefore it tends to want too snap your ancle
I’m about to buy one of these when they hit Australian shores, so at this point, now I’m unsure…………………
Damn, I will miss Marty! Get better soon, my guy!
@ElectricUnicycles,
Do you know that since autumn the power supply circuit of the controller and peripherals has been changed on Mten4? Previously, these were independent circuits, but now the controller, hall sensors, headlight illumination, headlight, taillight - they all hang on the same power branch. And if you have a short circuit, say in the headlight, then be sure that the wheel will level you. Compare the controller from mten4 last summer and autumn or the A2 controller and you will see that there are fewer elements on the board. This is an unforgivable reduction in price in my opinion. Low-voltage converters could fail on the wheels of the gotway, but it always carried the rider to the last. Now, thanks to circuit changes, this will not happen. It is necessary that the manufacturer return the old circuit and replace the controllers with controllers where the power supply of the microcontroller and the peripherals are divided into independent electrical circuits.
Very interesting analysis 👍
To quote the New Yorkers, the irony is that between a fire wheel and a cutout wheel, the fire wheel is preferred over the cutout wheel.
the fire wheel makes it go faster
I was riveted for every moment of this video. I may be in too deep. It was great seeing Marty smile from the doorway. Great video Roger!
Glad you enjoyed it!
Do we know how the crash played out that resulted in the broken bone? I'd love to know so that if a wheel does cut out I can "crash safer" via better understanding the possible ways for a crash to play out and mitigating for them ahead of time.
My bet would be that the spiked pedals played a huge role in the injury. Most likely one foot on the ground and the wheel pivoted with his other foot on it. He seemed a bit foggy on it.
Thanks Roj. We were all in suspense about the wheel. Like the Al Capone vault 😜😂
Sorry to hear about Marty, hopefully he has a speedy recovery. I'm watching this about 1 month into recovering from a broken foot after crashing my v12.
Roger - your vid was posted to the euc forum, and I came over to give it a like and say thanks. Good work.
Thanks for that!still a bit nervous to ride this thing.
Marty is one tough cookie he be back in no time 😼👍👍
Check the gyro's cutoff points when stationary leaning it left/right. It should be the same angle on both sides. I had a Gotway that had bad recalibration data stored, so it became unrideable. Among other things it cut off at different angles. A room temp calibration later and it was fine. Has been fine now for 10000km but at the time it felt like something was seriously wrong.
On a totally different note. I like the idea of putting backlit pictures in the nook between wall and ceiling! Looks great!
Thanks. Printed on an inkjet printer.
doesnt begode eucs keep internal logs? that would be one way to trace faults by software... again if the feature is available that is...
No data logger / black box memory on the board that i'm aware of. Would be a great place to check if there was.
Did you try pressing on the components on the battery while the multimeter was plugged in? Maybe pressing on the side while riding effected something
Good on you for doing this for Marty
He did for everyone.
Not finding anything is even more troublesome. Here's hoping this gets resolved...
Yeah... I was really hopeful it was the main power plug.
Dang that’s crazy the wheel completely checks out but still turned off on Marty
Gotta be main board.
Idea for possible causes
1, weak cells - You should test battery under load, unfortunately not cheap to test - you need something like "DL24MP Electronic Load"
2, Hall sensor / noise at board. - You can rule out motor by connecting it into VESC and checking if hall works at higher RPM
I was load testing it with me on it. over torqued to beeps a few times. No failure.
load can be easy to test, just plug it into a motor and apply a load
Did you freespin it? What speed does it cutout?
31mph
@@roghaj Probably not likely Marty cutout at that speed.
I wonder will they come out with a A3 or was the Falcon a shift away from the A2 look
Roger EUC ? some E-Wheel riders use a app with their unicycle. usually in that app there's DATA that keeps track of the unicycles operation. look over the DATA first.
No logging was active at the time.
Marty legless, one wheel on his wagon... too soon? You know we wish him well 🙂 Cold solder (UK we would call that a dry joint?) Talking about dry joints you could stress the PCB a little bit, a dry joint on there would do it. Plenty of opportunity on a main board. PCB's are flow soldered, a bit of a black art and you have to be meticulous, clean, and know what you are doing to get good results.
Dry joint sounds better. I might adopt that nomenclature. I do have a microscope that I use for PCBs, but the multilayer nature of these make finding anything a real challenge.
@@roghaj Hard to see the fault (though a poorly wave soldered board can be identified), easier to reproduce it through distorting the board, if that is indeed the problem. Small connectors too can be a problem. Intermittent, oxidized, dirty, indifferent quality (they are not likely to be gold plated which would be a norm in professional equipment). The springyness in the contacts of small connectors can work harden with age as well. Can be the devil in equipment of a certain age.
gotway don't change.
I had same cutout happen to me overpower but no beeps and threw me to the ground braking my sholder all I can say is take it easy at 50% or lower as you can’t ride it that hard gotta be gentle with it on the mten4 hope you figure it out I believe overpower maybe 🤔
Literally testing the wheel without gear omg man... Be safe mate! Well it was a nice inspection nonetheless :)
Crash, rinse and repeat.
@@roghaj totally haha
If the machine caused injury then it should be returned to the manufacture for examination before DIY disassembly.
I disagree. The manufactures have been known to cover up issues that would hurt their reputation. I have no skin in the game. Just wanted to answer the question.
you sound like someone who has no clue what they are doing
Be nice
I build drones I don't know if this could be the problem but the tec in a euc is a lot like my drones that's why I got into euc riding. Iv had two flight controllers that had bad gyros in them they would fly perfect but on landing and or supper fast moves they would cut power and fall out of the sky. The problem turn out to be from vibration to the flight controllers gyro.
I’m a drone builder too. Did bump testing to check the Gyro. No problem there.
Personally my theory is that this particular A2 happens to be racist. Its one of those thats only for Chinese peeps only so tell Marty to send it to me. I'm of Chinese ancestry so this A2 will do fine by me. Hope Marty gets a smile from reading this. Tell him to heal up soonest as we want his impressions on the Extreme 😅
How about insufficiently clean signals from hall effect sensors momentarily?
Wouldn't have made the machine turn off.
Whats the battery percentage when A2 cutout? You need to examine all the components on the PCB with magnifying glass. Once in the full moon, the computer misaligned mounting components on the PCB. Check all solder points.
Keep in mind that it did not cut out but it shut off, going ~12mph 🙂. There’s a big difference. The battery was pretty close to full
@@ElectricUnicycles Never quit EUC, Marty. God speed on your recover!
@@ElectricUnicycles is there video on this? Could be helpful on determining the cause. Also good luck with the recovery!!
@@Hunter_Heart thanks
evil ghost in the machine
Nice job!
It's probably not the A2s fault! Maybe it was Marty's! Maybe Marty had a muscle tension or collapse or nerve/brain failure due to his age! Lol! That shirt is nice though.
My usual stance is, don’t blame the wheel. However, in this case, I am making a hard exception.
Faulty capacitor?
I didn’t go so far as to test their capacitance, but they passed visual inspection. I don’t plan on testing every component on the main board one piece at a time. The only parts that would cause the machine to shut off while moving would be a full power disconnect. Almost every other air would result in the machine still being on after the failure.
How can it be faulty when Roger is riding it. Either the cap is blown or its not 😉
Just trying to understand what could possibly go wrong, but that makes sense, my assumption was a voltage drop, caused by a capacitor not holding charge or depleted by some other part of the circuit, but it makes sense that probably isn't the case if it can balance, & Roger was riding it that it was likely an glitch or rare set of conditions met. It's not like anyone has access to a dyno or parallel bars, & a treadmill to fully test it.
@@roghajTotally correct, actually if a wheel is still powered on or if its powered off, is a good indicator for a hardware fault totally cutting power off (machine off), or if its a software fault or slight hardware fault that has nothing todo with power delivery (machine still on)!
Capcitor fault would just give you a “weak pedal”, but no catastrophic failure (at least not directly).
So thats all pretty curious and in my view you have checked exactly the right components.
Unfortunately this feally makes a “zombie” wheel out of it…..
yea everything seemed like typical begode tech it sucks that it dropped marty tho that is super sketchy
Was Roger a EE or technician in a prior life - or just a clever autodidact? Thank you for this detailed troubleshooting session. Send it back to Begode for failure analysis? Maybe they'd be amenable since it did injure a high-profile EUC celebrity.
You’re too nice. I think I’m going to drop my lucky metal shavings in there and close it up to give back to Marty for good luck.
@@roghaj Give the wheel to Super Lady (Dawn). She can fix it 🙂!
Awesome 😎
Thank you! Cheers!
Four Loko😈💜
I think I might stick to hard liquor.