First Look at TorqueBoards Direct Drive Motor

It would work with normal firmware, just run canbus between the rear Vesc and canbus between the front vescs then connect both lots through split ppm

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@everyonewhowantstousepneumatics

An axial direct drive with pneumatics isn’t going to work, the only exception being one with stupidly large brushless motors wound to a very low kV. The beauty of a reduction system is that the amplification of torque is directly proportional to the gear ratio. Decreasing the kV of a 6374 motor doesn’t amplify the torque as a reduction does.

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So the same principle would apply to the Carvon direct drives as well? I was hoping to go pneumatics too with a stealthier look from either the carvons or the TB direct drives on a 2WD as going 4WD at least in the case of Carvon’s V4TD would cost more and weigh much more as well

Yeah, the same principle applies. It’s the exact same thing. Carvon torque drives are just slightly modified $99 Koowheel hubs - kV is way to high, and torque way to low for pneumatics.

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Well that’s disappointing. Probably why they recommend going 4WD on it when going pneumatics. When you put it that way it makes me want to try building my own but i think id be way over my head as I dont have the skills or equipment to do so :frowning:

No - because the firmware would not send most power to the front wheels at low speed and rear wheels at high speed – and wouldn’t send braking to the rear wheels except hard braking to the front wheels, on a linear split.

This could be added, though - like a traction control module in the software.

Ahh got ya, you want it to change power at different ends depending on speed.

@Ackmaniac is there anyway to do this? It seems kinda cool

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With my firmware mod it is possible to adjust different acceleration and brake power at front and back axle. For example 30% front and 70% back during acceleration and 70% front and 30% back at braking.

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but decreasing kv does increase torque and its directly proportional to current, you could say that’s it’s beauty. there are many vehicles with hub motors successfully running much bigger wheels such as with a bicycle and with a low kv. you could call a bicycle hub motor stupidly large if you want and it’s true you could get more power out of a smaller mid-drive with pulleys, but if the hub motor is larger no pulley is necessary and just as good efficiency can be gotten if not possibly better as well as many other benefits. but i hear you and at some point the wheel becomes too big for the motor and its kv and it will be less efficient.

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Torque is determined by the number winds and the strength of the magnets in the system. To lower the Kv you have to increase the number of winds and for any given volume of copper you can fit around a stator, increasing the turns of the wire decreases the current throughput because the wire has to be thinner. That’s why hubs heat up more (and are always going to be less efficient than a satellite system), you can’t rewind a 3000w 6374 for torque and expect to be able to push 3000w through it again.

An e-bike uses a stator engineered for torque - it has a shit tonne more magnetic poles and motor teeth than recasede 12t14p 6374.

You can’t just make the motor larger and call the system more efficient!

:+1:

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had to add inside

but…yes adding more poles adds more torque. so yes more magnets and poles you can say adds more torque as it lowers the kv, but youre trading copper losses for iron. which may be good and ideal in some cases depending how fast the motor goes largely. that’s my take on it all. happy to hear any disagreement! but besides that point i also still think a direct drive is capable of the same efficiency as a pulley drive in our typical application. maybe not ideal on the steep uphill but overall. going up the steepest hill…i think you could use a bigger motor with the right kv and you’d be as efficient.

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Yeah, I know. Also generally by increasing the teeth, you increase copper fill.

I was thinking more along the lines of the physical restraints imposed on a system when you make the motor larger, which was why I said you couldn’t call 'the system more efficient" as opposed to “the motor more efficient”. You’re right - a larger motor is more efficient than a smaller one given they both operate in the same conditions. The bone I’m picking at is the design of the system - efficiency isn’t just for the motor, it’s the collective efficiency of all the subsystems together.

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id have thought increasing the teeth would likely decrease the copper fill. not that ive compared. i imagine with double the teeth if you keep the same overall iron content, so instead of a 2mm thick tooth its now 1mm, the copper content could potentially be the same here with 1mm slots instead of 2mm and each of those slots now having half the fill, so equal…except when getting more and more teeth there is a mechanical limit and they have to be so thick to stand up to vibrations and physical forces, especially so on a skateboard, so at some point the smaller teeth necessitates having less copper eventually as it needs to be iron with the bigger teeth so they dont bend or break. (although thinking about it again, alone here, if the stator were designed to have teeth with no slots, with the diameter being complete iron, that would give a lot of support and maybe you could get away with the 1 turn per tooth motor im talking about below…and benefits of no cogging and smooth coasting)

but surely with more teeth you COULD get better copper fill if you just decreased the ratio of iron to copper. and maybe that would work well and making me want to try modeling motors again

but in adding more teeth and dropping the kv that way, as apposed to doing it with more turns of wire, …id like to see how that would go. It would be probably more work to build but assuming the teeth are still strong enough, at lets guess 36 teeth, and before with 12 teeth the motor needed maybe 10 wire turns to get to the desired kv, maybe now it would need a third of that, and at maybe 3 turns…and going along those lines maybe if 50 teeth are strong enough you could do a single turn in the slot and then you could maybe have a cast piece inserted instead of trying to fit in cylindrical wire, or have the slot just the right shape for a shape wire, and therefore get 100% fill as apposed to even best case with cylindrical wire is roughly 85%.and still achieve the same kv. but the iron losses at speed would suck and now it’s an uphill monster only. and surely not so simple and its assuming the motor were designed so that all those small magnet fields went where they were supposed to go

back on point…how many teeth does the stator have @torqueboards

I have 24 teeth. Molars are gone now.

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Try adding more teeth but next-to instead of in-between the other teeth. You’d need to write custom firmware to drive it though… but it could possibly lower the kv without thinner teeth or thinner wire. So imagine two stators on the same axle but offset relative to one another so each tooth was “grabbing” the magnet at a slightly different time

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I still have molars

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i like turtles

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ok ok forget the side tangent please. and back to the motor!? where’s the motor?

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Yeah, don’t think it’s coming soon, torqueboards is pretty silent about it. Too bad, because they would be completely unique in the market if they could make it widely available + reliable.

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Yeah after realizing how difficult it is right now to contact Jerry from carvon or get a hold of any of the drives, Having these would definitely give the market more options. I asked customer service and they replied that it would be ready in 2-4 months which is indeed awhile.

Ah well, gives me more time to get the rest of my parts together while waiting lol

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