I remember when the original ones came out far longer back than I like to admit. I could never get the hang of it with 1 wheel each end.
A random thought i had:
It would be interesting to be able to lock/harden up the steering when going very high speed. Some e-scooters has this function on their steering wheel when going high speed, so the steering is depending on the user weight.
Some kind of iteration of that control
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I had this idea a while back for luge.
Never built it, but we called it the go brake.
The idea was a brake lever for each hand on the luge rails that would control the front/rear trucks.
It was one of my favorite ideas that couldn’t see the justification of actually trying.
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Has anyone tried printing a super thick sound blocking TPU case for BN m1 drives?
I wonder if 1cm of 15% or 20% 3d honeycomb infil would dampen the scream I get at 25mph+?
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Was thinking about this last night.
Go Kart tires on an Eskate.
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Sorry my friend, but twampa already TM that idea 
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Do itttt
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no way steel gear teeth would not win in a short time scale.
if it somehow did hold then RIP wh consumption.
hmm rubber drive connection, sounds familiar…
Just run two belts for reliability
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Is there actually one that was made?
Made? Idk if they made / created the mold, but they sure have tires that was used for go-kart and golf kart, then now brand them as esk8 tires
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I mean, if you do it right, the gears should never be touching the case anyway, only air.
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Liquid silicone. . .
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Oh oh I misread and was thinking about coating the gears. Seems like what you want is gearbox cases made of cast iron or something to reduce the noise from gears.
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Has anyone suggested or tried a sort of high capacitance switched buffer for eskate packs before? Basically at power on a pwm switch charges a biig capacitance bank from the battery at a relatively comfortable discharge rate for the cells, like much bigger than existing ESC caps. Say you’re using high capacity 21700s like an LG M50, charge the caps at 5-7A as opposed to Mooch’s recommendation of keeping at or below 10 and the datasheet of 14.4A temp limited. The buffer remains cut off from the ESC until it’s reached operating voltage, and continued to charge while the ESC isn’t hitting the battery hard.
So if you need to floor it at speed to overtake or make it up a hill or something else that would push your high capacity cells into serious sag and/or ageing territory, you’ve got a buffer that can help you out. It effectively keeps the cells running more often but limits the peak drain. Or alternatively, you continue to blast the cells a bit when you need to overtake but now you have bursts of much higher power available for field weakening. You can gear low for the majority of riding for efficiency and (IMO) a nicer ride feel, and then yeet into the sunset if needed.
I haven’t done the maths on this in case it’s not obvious, but it would be really cool to see a ~3P pack made of high capacity cells that can act like a high discharge pack for short bursts, given we don’t usually have high sustained loads. I know this sort of counteracts some size benefits of using a smaller pack but packs are usually wider than ESCs, so stick it on a brick alongside the ESC. I’m hoping that you could achieve a high enough peak power boost that it would justify itself but idk how the weight, size, and cost stack up vs more cells in a bigger pack
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Ultracaps are great for millisecond bursts or shorter. Much longer than that and you need a lot of them. They can deliver tons of power but have almost no capacity.
Their low voltage rating causes problems too. For a 12S li-ion pack you would need at least twenty 2.7V rated ultra caps in series along with a 20S BMS just for them. You never want to even get near their voltage rating so 2.5V each is max.
Using them in parallel with a li-ion pack also means we are only using a tiny bit of their available voltage range. Going from 50.4V down to 33.6V (2.8V/cell in a 12S pack) only uses 0.84V from each cap. All the rest never gets used and typically much, much less of their available power would be used.
If you took twenty 100F caps the size of your thumb and got them wired up in series with their own BMS you’d have a large 5F, 50V cap pack. You might also need the circuitry to switch them in/out of the circuit but perhaps they could always just stay in parallel.
That pack of twenty caps would give you about 2 seconds at 40A before the cap pack dropped to 33.6V. Since the li-ion pack wouldn’t discharge that fast the caps could never deliver that 40A and the caps would share some current with the li-ion pack. They wouldn’t have much of an effect.
Bottom line…adding another 1P string of good li-ion cells would give you more power at a much lower cost, be more reliable, and take up less room.
I have to admit though that your idea has fascinated me for a verrrrry long time, ever since I worked with a client to parallel ultracaps with A123 cells to create small packs for unsticking snowmobile and car engines in cold weather. Worked incredibly well but we only needed six caps in series.
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This one is reliant on tech that I don’t think we have, but…
What if you had an esc that recognized each as a separate power source, and only drew from that 40amp 2second burst cap pack at it’s top end, or as a “turbo” button? Would the caps charge fast enough to even use often at all?
Could be pretty cool to have a low power board that can burst an extra xx amps, even cooler if it had a turbo gauge on the remote.
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I was also thinking about it from the other direction as well, there can be a buffer where braking energy can go and get charged back into the battery at a safe current amount over a longer period of time. You can then run high braking amps for even more effective brakes without worrying about the charge current going too high and reducing cell life, or wasting energy using a resistive setup.
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LOL…that gauge would be cool.
I don’t think we get any benefit from having them completely separate. The caps are still only capable of delivering 40A for two seconds before hitting a low voltage. You can easily get that from adding another 1P of of P42A’s.
The caps would drop their voltage fairly linearly over that two second period. You would have to compare that to P42A’s which would have a larger instant voltage sag but would then not drop their voltage much after that. Which would end up delivering more power?
Maybe if you had forty caps in series, with their BMS and electronics to switch them in/out, and dumped that huge burst of power into the motors. That would actually use the caps much more effectively. But now all the electronics need to be rated for that higher voltage.
I think it would be hard to beat just adding more cells in parallel and using very low resistance connections internally/externally for the pack (better spot-welding, copper inter-connects, better connectors, etc.). Especially when considering cost.
I would love to test all this…fascinating concept…but too much time/money.
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Unfortunately, we’re constrained by the same low capacity for ultracaps here too. If we can only discharge at 40A for two seconds then we can only charge at 40A for two seconds before they are full.
Then we have to make sure the caps are at a higher voltage than the pack so current can flow into the pack and then allow the caps to discharge at a controlled rate into the pack.
It’s all possible, and allows for lots of regen current, but verrry expensive and large. Would love to see it done by someone though.
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I think capacity would be slightly less important for braking though, as the amps would quickly fall off as speed is reduced. It would only need to take the initial excess hit, while the rest would flow into the battery as normal. It’s not like the braking energy goes solely into the caps - it’s only capturing the remaining energy after battery amps gets maxed out.
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