Making Begode wheels safer: PWM tiltback with custom firmware

[Mike Sacristan]

2 hours ago, Freestyler said:

I have asked several people to tell me their max PWM and no-one has overshoot by more than 10% PWM.

This makes me wonder if I did in fact chose a conservative number or people don't push their wheels as hard as I thought.

The truth is probably somewhere in the middle. I took the worst possible outcome out of several attempts where people tried their best to overshoot.

But this was done at 50% PWM where people knew they were safe no matter what (they weren't going to overshoot by 50%).

No one in their right mind would actively try to overshoot as much as they can when the limit is set at 80%.

 

My goal was a zero cutoff percent chance due to an overspeed no matter how bad someone screwed up.

After gathering so much feedback from many people on different wheels, I guess it's time to increase the hardcoded value to 80% for wheels that go up to 105% and 75% to wheels that go up to 98%. (in other words, leave the default PWM limit as it is in the stock firmware)

After all, Kingsgong has it's limit at ~88%, Leaperkim at ~82% (newer wheels) etc.

 

The beep + tiltback implementation is insanely good.
The wheel beeps and initiates creeping tiltback which then gets more and more pronounced.
The beginning stage of the tiltback can hardly be felt. Which means that the beeps almost act like a prewarning.
And the increasing tiltback just slows the rider down... sometimes brutally if they really smack into it and they sure get their posture corrected quickly.

80% definitely sounds like a good number! If someone wants to donkey it all the way to 90% they will still be good!

75% is more of an idiot proof number.

Kingsong limit is insane lol... we have seen how that goes. And yeah the Sherman Max... what a horror.

Sunny day tomorrow! I will fly my EXN to the mooooon! Thanks again for all your amazing work!

[GottaWay]

I ride a MCM5V2 800wh. With the custom tiltback firmware set at 70% pwm, I was able to push to 81.6% pwm one time as recorded by Freestyler's web app. This took me running the battery down to around 50% and pushing more than I'd comfortably push had I not been testing. Ambient temp outside was also 25C(battery was room temp to start). Speed topped at 41kmh. Max temp read 27.82C.

 

After these runs today, I flashed a custom 80% pwm firmware. Pushing similarly, I hit 84.6% pwm with a top speed of 41kmh with battery between 45-50%. Same outside temps. Max temp read 29.66C. Knowing tiltback kicks in 10% later, I did not push against the tiltback nearly as hard. I did ride aggressive to get up to the pwm limit though.

 

My prior testing had me only hitting 75.5% pwm. This involved "surfing" the tiltback lightly, where the light flashes but tiltback is barely engaging, for a few km at a time. So this involved manholes/potholes and a peak speed of 41kmh. Again, at near 25C temps but with more than 50% charge for most of the riding. I did try and push against it, for science, and still only achieved 5.5% over my set limit. The tiltback is strong at 5.5% over and more than I'd care to continue to ride, so I ease off.

 

I only have a couple quick blips down the street on 80% pwm. Given that I rode 1050km with only the gotway beeper going off at 75% and then around 100km on 70% pwm tiltback firmware, I feel 80% should be suitably safe for me and my desires. I'll get some rides in and see in due time. I could see where 78% might be SLIGHTLY safer, especially on a wheel that cuts out at 98%, but I need some ride time to decide that.

 

Freestyler, thank you! You've been a huge asset to this community and a pleasure to communicate with.

 

 

[Mike Sacristan]

So yesterday I flashed the EXN to 80% dynamic tiltback. Thanks again Bill!

Went for a cruise with my friends today... floored it as soon as I left the house... got to a nice high speed and 78% PWM and the wheel did not beep.
Rode some more with the guys... then on the way back home Fredde was on his EXN HS and we were riding on a long straight. He was riding along there at around 50kmh gently accelerating and waiting for his beeps lol. I ripped past him and started beeping, hit tiltback, pushed even more... and actually achieved 86% PWM at 62kmh and sagged down to 81.5V. I also pulled 70A (140A) shown on DB. Needless to say Fredde ran out of balls since once a wheel beeps you kind of wonder if it is yours or not... unless you have dynamic tiltback. Then just yolo.... 

All the numbers look good to me.
"Slow speed" overshooting is easier than high speed overshooting. Or rather... it is easier to overshoot 60kmh than 70kmh.

[InfiniteWheelie]

On 1/12/2023 at 1:57 AM, Lefteris said:

So, you managed to get the whole veteran firmware update process, great to know, that opens up possibilities!
(please tell me more mastah 😂)

Time to fire up that IDA 😁😋
cc @Freestyler

Does this open the door to PWM tilt back for LeaperKim wheels? I really want this on my Abrams.

Edited January 15, 2023 by InfiniteWheelie

[Optimus_Prime]

Question, how do you set up the PWM? I'm having trouble. You members make it look, so easy.

What are the steps, I need to perform to set me wheel?

Thanks, in advance.

 

[Lefteris]

13 hours ago, InfiniteWheelie said:

Does this open the door to PWM tilt back for LeaperKim wheels? I really want this on my Abrams.

We are far far away from that Galaxy...

i'm trying to map the firmware addresses etc.

[lattisimo]

On 1/14/2023 at 10:49 AM, Lefteris said:

stm32 chips have read protection, it's quite difficult to do so... 🤔

I have started my research. It may take me a bit to determine what protection they are using and what exploits are available, hefty learning curve. Have a few ideas on how to mitigate some of my risk but not holding my breath for a solution just yet.

[GottaWay]

Just had a chance to take a quick rip on the MCM5V2 with a full battery on 80% pwm tiltback firmware.

Short story, I think, this is exactly what I wanted.

For references, Freestyler's web app says pwm alarm would kick would at 47.8kmh @ 100% battery, 45.7kmh @ 80%, & 42.5kmh @ 50%.

I hit my speed record on the MCM5V2 comfortably today at an a bient temp of 4C (wheel was kept indoors at room temp prior to ride). 46.2kmh with a max PWM of 84.4% (that's 4.4% over my "limit"). Stats from the ride read: Current Battery=80.6%, Max Battery=100%, Min Battery=42.2%, Max Speed=46.2kmh, Max PWM=84.4%, Max Phase=51.8a, Min Phase=-48.5A, Max Temp=35.11C

Seems to be exactly what I wanted. I'm able to ride very close to the rated top speed of the wheel with some sense of safety now. It's awesome.

[Asymeel]

@Freestyler

Thank you so much for your amazing contribution for EUC community !

I saw that you managed to change the Mten4 to 100V. I would like to experiment it with mine 🤗🤗🤗

I currently have Mten4_GW1011004 official firmware installed. I needed it because I have installed a kill switch button.

Is possible to provide me a custom firmware based on this official one + the 100V activated with the procedure to implement it (I already saw the video with the proxy change to install CFW via Begode app)?

And I let you decide about the PWM value based on others experience/feedback. 

Thank you very much 🙂 

Lucas from Switzerland

[Timwheel]

Hello @Freestyler I can't seem to use the method you sent me that work a few months ago, did you change some settings ? Thanks a lot ! I did my master but I can't find the mcm5v2 software, I now have a blackboard

 

Tim

Edited January 20, 2023 by Timwheel

[Justin38]

Hi @Freestyler, Thank you for all your work on begode firmwares, do you think it's possible to modify the firmware of a Nikola card (side mount) to put it horizontally at the top of the wheel, I'm making a custom wheel and I I prefer to put the batteries on the side of the wheel than at the top to reduce the center of gravity, I hesitate to use the firmware of the hero but I may have stability problems since the hero is 18 "and my custom 16" and not the same weight 

Edited January 22, 2023 by Justin38

[Lefteris]

2 hours ago, Justin38 said:

do you think it's possible to modify the firmware of a Nikola

Only if the Nikola has a program-abled board. The black motherboards are usually upgrade-able from the app using firmware.

[Justin38]

19 hours ago, Lefteris said:

Only if the Nikola has a program-abled board.

Yes I understood, what I wanted to know is rather if it is possible to change the orientation of the card in the firmware because a side card cannot be calibrated when mounted horizontally at the top of the wheel 

[Lefteris]

1 hour ago, Justin38 said:

Yes I understood, what I wanted to know is rather if it is possible to change the orientation of the card in the firmware because a side card cannot be calibrated when mounted horizontally at the top of the wheel 

Sorries, got it! Hope you figure it out!

[bracky72]

How do I get this cool firmware onto my wheel?  I’ve read the whole thread and it’s still not clear.

[Freestyler]

21 hours ago, Justin38 said:

Yes I understood, what I wanted to know is rather if it is possible to change the orientation of the card in the firmware because a side card cannot be calibrated when mounted horizontally at the top of the wheel 

Sorry, I don't know how to do that yet :/

[Vince.Fab]

It would be really cool to just be able to recalibrate a motherboard in any mounting orientation.   I just swapped MBs between an EXN ht to a RS Hs, had to flip them and mount in original orientation to work... that was fun lol.  

 

Also in case you guys didn't see, Euc World's new app update adds Freestyler's firmware updates!

[Rawnei]

3 hours ago, Vince.Fab said:

It would be really cool to just be able to recalibrate a motherboard in any mounting orientation.   I just swapped MBs between an EXN ht to a RS Hs, had to flip them and mount in original orientation to work... that was fun lol. 

Sounds like a huge oversight on Begodes part?

[Seba]

6 hours ago, Vince.Fab said:

Also in case you guys didn't see, Euc World's new app update adds Freestyler's firmware updates!

Yup! EUC World 2.30 is out, so now you can easily install both stock and @Freestyler's custom firmwares. You can switch between two, you can also downgrade and upgrade at any time.

[Cerbera]

1 hour ago, Seba said:

You can switch between two, you can also downgrade and upgrade at any time.

What are the chances of bricking a Master if I do this ? Just thought I'd check...

[Seba]

5 hours ago, Cerbera said:

What are the chances of bricking a Master if I do this ? Just thought I'd check...

Same as with every firmware update. Downgrade is just an update using older firmware

[moarmoto]

Thanks for this amazing work.

I just bought an extreme bull commander (will be shipped soon)

From what I gather,

1) EBC does have black board and interfacing with it is technically possible

2) EB hasn't released original firmware nor any subsequent updates

3) so there is no baseline from which you could implement the enhancement to alarming using PWM.

 

[fbhb]

19 hours ago, Seba said:

EUC World 2.30 is out

Thanks for this @Seba Will the updated Wear OS companion app be available shortly? Sorry for off topic, Cheers.

Edited January 27, 2023 by fbhb

[taiguy]

Anyway to pull my current firmware off my master for patching? It's an oddball version.

[chuvisco]

13 hours ago, taiguy said:

Anyway to pull my current firmware off my master for patching? It's an oddball version.

What firmware are you on? I’m on GW2014503 and thinking I might be in the same boat.