Not my build but this is crazy sick. Wind turbine driven snowboard. Also super cool input for the remote control
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Looks like this one
I am really curious how much acceleration this actually gives.
It moves the unladen board but will it move an human ?
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Iāve always been trying to figure out how to make an electric snowboard. I thought about an edf, but I didnāt think it would have enough power to push someone, is it able to?
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Well
If you look at a single sk8 , rated for 4KW by the same eople who rate this EDF at 1600KW (edit: 2.1KW), so lets say about 1/2th the amount of power.
Wheels and fiberglass on ice probably have the same order of magnitude in frictions. maybe twice or half as much but not a 10x reduction or something crazy. Lets say theyre 1:1 for arguments sake.
The problem I see is the power delivery of the EDF. The losses are pretty substantial. Lets assume something 1:3, in favor of the wheels on tarmac.
By that estimation, this board with this motor will deliver something like 2/15th the actual AFFR (thatās Ass Felt Force Ratio) compared to a hobbyking 6374.
Dont sniff thsose ratios, you donāt know where i got them.
Im sure this will give you āsomeā power, but its not going to send you racing uphill to beat the lift
EDIT:
Source
quick bit of research:
āThe propulsion efficiency is then 86/118 = 73%.ā
I did a hard TLDR so that number is likely missused for our case here, but the benefit of ignorance ups the AFFR from 2:15 to 4:15th of an sk3 6374.// EDIT: I cant read and am drunk,2KW motor ups the AFFRagain to about 1:3 or 5:15
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They have another one as well
But that one is 1600Kv (rpm per volt) not 1600KW (kilowatt)
They rate these at 2100W and 3700W and they have very adequate cooling, especially if used only on snow. Itās almost best-case-scenario for getting the full rated power from the motor. Relatively constant RPM with awesome cooling.
Though I wonder if you could disassemble one of these and put a bigger motor on it.
Of course none of that matters, because these are out of stock and unobtainium
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Honestly the way I understand this is you need about 4 of these with upgraded motors and youāve got something equivalent to roughly a dual 6374 setup hahaha. Thas damned reasonable imo.
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Thatās not unreasonable, the bigger ones are 94mm diameter. You could fit 4 of them in a 20cm x 20cm areaā¦ But how much power would it take to push you up a slope? How far could it go? We need some @professor_shartsis insight here imho
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Thats really the question here, cause the best use would be do get around absurd lift ticket prices. I scoff at a 140$ for Mammoth you damned goblins!
Given the magnitude estimations as made before, Iād consider 4 of these a pretty assured way of achieving some way up the hill.
So Lets assume, 1/3 power efficacy. 75kg rider+gear, and Mammoth mountains lame 610m slope height.
Energy required to lift the rider up the mountaing 0.5 x 9.81 x 75 x610 = 224ish KJoules. or 63ish KWhours.
lets say 4 of those puppies , with the 1/3 power efficacy is about 4 x 2.1KW / 3 = 3ish KW usable power in the board.
Im drunk and this is likely wrong, but that works out to just shy of 21 hours to get up the mammoths paltry 610 vertical meters
ok so I need to retake phyics 1, the 0.5 factor is for kinetic energy not potential gravity. therefire the umbers all double to ~42 hours
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Sounds like battreries arenāt going to cut it yet. Might have to be a kerosene drive which unfortunately isnāt clean. Maybe someone can make one that runs on fryer greaseā¦
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Did someone say pulsejet?
You would have a nice hot thing to warm you up when playing in the snow. It probably would dry you off pretty well too.
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i just had some painful flashbacks from calculus
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The inevitable ultimate truth of math helps me sleep at night.
But it does mean you need roughly 900 Whour pack. Or the equivalent of 3 x 10s4p (330Wh) packs. @b264
Achievable but incredibly impractical
If you used some form of studded tires with efficiency similar to that of a regular skateboard , it could be done on a single large pack. Once.
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Not really, I have a skate with a 1kWh pack (10S10P) and another 1kWh under construction
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I really need to do this, do you charge like once a week with it? or do you travel long distances?
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If I make a 10S2P with 15Ah Headway LiFePO4 cells, thatās over 1kWh and less than 10kg, so why canāt all yāall make 1kWh in Li-Ion for less than 4kg, which is still way manageable?
I always fancied a set of these
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For this one itās probably better to think in terms of thrust. With 40-80 lbs force thrust should be equivalent to a single or dual drive with modest settings. 100+ lbs force thrust would be equivalent to high amp settings, high gear reduction or having 4 motors.
80lbs force would be equivalent to about 355 newtons.
it looks like with 4 of the motors youāll get about 33lbs force so enough thrust for maybe 20mph on a 5% slope (very rough mental estimation).
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