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Hyundai Uni Wheel electric drive system could revolutionize EV design

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Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#91

Post by tlb »

KaiserPro wrote: post #83

I love innovation. There still needs to be a CV joint to allow steering, but short of hub motors[1] There isn't much you can do about that. What I would be interested to see is how lubrication works. Do you think they just have a bunch of oil in the bottom and rely on centrifugal force to fling it to the ring gear? Then let surface tension transmit it to the sun gear? [1] They are heavy and heavy wheels affect ride q…

The hard thing with lubrication is sealing it so it doesn’t leak. Considering the pinion gear and shaft moves in 2 axes relative to the housing, that could be tough.

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#92

Post by consp »

benj111 wrote: post #65
husam212 wrote: post #56

Earlier quoted context omitted.

Maybe the motor is supposed to turn with the wheel, that doesn't sound like a good idea.

Why not? You'd have an added complication of making the shock absorber the pivot point, and attaching the motor to the top point. Or having a separate pivot point where the motor or wheel can slide up and down. This does raise the question of why not just attach the motor straight to the wheel. The standard response to that is a hand wavey "unsprung mass". But has it actually been tried and shown to be an issue?

> The standard response to that is a hand wavey "unsprung mass". But has it actually been tried and shown to be an issue?

Afaik with high performance motors, if you want optimal performance and space efficiency you take the unsprung mass for granted and move everything in wheel and try to reduce the mass as much as possible. As a bonus you do not need joints, just a planetary gear system.

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#93

Post by [deleted] »

hooby wrote: post #74
jillesvangurp wrote: post #71

Earlier quoted context omitted.

Probably a combination of having some way to rotate wheel + motor around some axis and the ability to simply vary the motor speeds on each wheel independently.

But then you need empty space around the motor, so that it can rotate there. That somehow seems a weird choice for a device that's all about improving space efficiency.

[deleted]

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#96

Post by 20after4 »

hooby wrote: post #47

The thing I see not mentioned in the article/video, is how the wheels can tilt/turn/angle - without needing a CV joint again. The designs seems to cover all the motion of the wheel in the suspension - but I don't see how this could accommodate steering. Is this for back wheel drive only? Curiously the animations shown in the video, show the uni wheel used in the front of a front wheel drive car - but without ever sho…

The next logical step would be integrate the motor directly into the wheel. With 4 wheel drive motors it wouldn't require huge motors, they could each be small enough to be packed right up against the inside of the wheel.

I'm actually surprised they would even need the gearbox. Why not just put four Outrunner[1] motors, one on each wheel, and let the wiring be the only thing that has to flex when the wheel is steered.

1. https://en.wikipedia.org/wiki/Outrunner

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#97

Post by idiotsecant »

20after4 wrote: post #96
hooby wrote: post #47

The thing I see not mentioned in the article/video, is how the wheels can tilt/turn/angle - without needing a CV joint again. The designs seems to cover all the motion of the wheel in the suspension - but I don't see how this could accommodate steering. Is this for back wheel drive only? Curiously the animations shown in the video, show the uni wheel used in the front of a front wheel drive car - but without ever sho…

The next logical step would be integrate the motor directly into the wheel. With 4 wheel drive motors it wouldn't require huge motors, they could each be small enough to be packed right up against the inside of the wheel. I'm actually surprised they would even need the gearbox. Why not just put four Outrunner[1] motors, one on each wheel, and let the wiring be the only thing that has to flex when the wheel is steered…

Hub motors have existed for a long time. The issues you'll have to overcome are the same.

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#98

Post by geoduck14 »

20after4 wrote: post #96
hooby wrote: post #47

The thing I see not mentioned in the article/video, is how the wheels can tilt/turn/angle - without needing a CV joint again. The designs seems to cover all the motion of the wheel in the suspension - but I don't see how this could accommodate steering. Is this for back wheel drive only? Curiously the animations shown in the video, show the uni wheel used in the front of a front wheel drive car - but without ever sho…

The next logical step would be integrate the motor directly into the wheel. With 4 wheel drive motors it wouldn't require huge motors, they could each be small enough to be packed right up against the inside of the wheel. I'm actually surprised they would even need the gearbox. Why not just put four Outrunner[1] motors, one on each wheel, and let the wiring be the only thing that has to flex when the wheel is steered…

I agree, hub motors [0] have been around for over a decade and are used to power EVs in races. I don't really know why these aren't being considered here.

[0]https://www.explainthatstuff.com/hubmotors.html

Re: Hyundai Uni Wheel electric drive system could revolutionize EV design

#100

Post by kibwen »

BHSPitMonkey wrote: post #58

Regardless of the merit or practicality of the idea, I really loved the video and the animations. I'd happily watch a series of cars and other complex machines explained in the same style.

The video is good, but I couldn't help but draw a parallel to the famous Rockwell Retro Encabulator: https://youtube.com/watch?v=RXJKdh1KZ0w
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