Trillium Hub Motor

Well there is, and I realise bigger motors handle more current that’s why I said “apart from”. I was asking if larger sized motors create more torque, which would make sense and is what is generally found

My kind of thoughts are, bigger stator bigger magnets, bigger magnetic forces results in more torque.

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I looked at the numbers again. I was mixing things up. I simulated 4.45Nm/230A = 0.01935 Nm/A

493kv or so, but let me re-sim things.

Thrust should be 4.45Nm / 0.042m = 106N per motor, which is plenty.

This is only 21A/mm^2 current density. It can be increased to about 45A/mm^2 so I expect 660A will work just fine at approx. 12.77Nm. I don’t have any plans to pursue a 660A motor controller, as its another $40 of controller to make.

The thing is, that’s an insane amount of thrust for a skateboard. You have to be strapped in. This is why we need to dyno test Hummie’s motors, because I suspect they are saturating well before your 13Nm number or you guys are just insane. :smiling_imp:

If he is truly at 13Nm, that’s great. I think you’re better off though with 4WD and more urethane with that kind of power level.

I might take it up to the 300A level and lengthen a little bit, but I need to model up the ronin trucks first and see what looks good.

And more resistance :thinking:

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Yes actually you are right. Turns is correlated with Kt, and torque = kt * current. In most of our builds where our motors basically cannot be over-volted and where gearing is a thing, current is basically the only way that motor selection can affect output power. Voltage is already limited by our ESCs, so the only thing we can play with is finding ways to increase motor current.

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There are so many challenges for this build! Even just wires and connectors desoldering themselves! But it sounds like you know your physics, and I imagine you might have had a few sleepless nights thinking through the engineering. Keep us posted!

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Maybe the reason why @Kug3lis 80xx motors become more hot than his 60xx ones :thinking:

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17mph top speed?

field weakening will get it up to 23-25

That’s pretty slow IMO and with “boosted” level torque it’s gonna be super weak. Imo a meepo will perform about the same but you get a whole board for the same price.

So what is the acceptable conversion between $ and thrust per wheel?

@hummie is doing what $425 for a set of trucks with two hubs? 311N per $212.50 (one motor/one truck). $0.68/N. So my hubs with two trucks need to cost $72 each, or double that if I pull off a 660A controller. That might be workable.

What would you guys say is the max you’d pay for a premium dual motor + two premium downhill racing trucks + dual controller combo + 90mm wheels? Everything but battery and charger basically.

Separately, what would you pay for the same setup but 4 hub motors instead of 2?

if you’re going the route of a custom ESC, why not build one that can handle 75v-100v and a motor which is around 73kv? then you can get the better performance than presently available (same torque but higher top speed)?

We will make a version of the ESC that will do higher voltage, but to increase the urethane it helps to get the motor diameter down, which is what I’ve done with this 1S motor geometry. However, if I did higher voltage I would need to go to a larger diameter motor because there isn’t enough space to fit the copper in smaller diameter multi-turn motors. The OD is only about 52mm. so a 90mm wheel would give 19mm of urethane, which is better than average right?

FYI most of the DIY community thinks Boosted is very very very slow, I don’t hate on it it’s a decent board but it shouldn’t be the one your comparing your self to, not here cause it’s not impressive.

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I’ll from now on just compare to hummies.

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i believe many folks also want efficiency which is generally achieved by making the motors and copper mass larger…

@pat.speed if the KV is the same then different size stators will produce the same torque for the same quantity of motor current, but the larger stator can handle more current before it becomes magnetically saturated – a state which means the torque no longer increases with a linear relationship to motor current.

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What does the split wheel do for you guys cosmetically?

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to be honest i would feel safer on a completely unified contact point/pitch

but i could definitely be proven wrong x)

it does look sick though, very future…y

This is 90mm OD x 65mm wide https://uc346518667fe9825f6052a830b6.previews.dropboxusercontent.com/p/thumb/AAPe2IQvcRcUpJfPUo4TVOfklggqS7CoY3oij6b0bnUvjIy4p3lRNED3Pq8zUhgU56m_viupJFkMcbBsF7w8FQ8ICchyy0VKryKw1iy1UieV39AthAJQ4x-7AuUpVI_ziKJNSqn1ShmIpnPzg5IQcMeRGyGEGEYNoihaiKKmGpcl5Qn0vp2dM2VrYcApfGCFBd9V73QkR6OTsBwEKg6FMIZ1NvahTe35Ep5EFOrmNbDmIw/p.jpeg?size=1024x768&size_mode=3

whatever happens i just hope there is an option for pneumatic wheels. the roads near me are just awful :tired_face: