Reinvent the Wheel

It all looks really good but I am a little weary about damage to the exposed ring gear.

Overall looks like a really promising improvement over existing electric vehicle independent wheel mounted motor arrangements.

I'm a little wary about damage too. If you hit a curb, you could do some expensive damage, I believe. And how do you change/replace the tire?

It is a little hard to see, I think it is a single outer hub nut and then three nuts on the bearing spider hub and the front bearing spider comes off clean which allows the wheel (and associated attached ring gear) to simple come off.

Not too different or difficult.

Well I think you're right you can't have the gears exposed like that for one thing...and it seems very loud under heavy acceleration....plus everything said is very general, no real statistics...I don't see any advantage over a typical hybrid drive system...I'd like to see them try this on a gravel road...The general lack of information seems to be a red flag...

I would like to see the HMMV tested under real field conditions:sand,mud,gravel,shrapnel,etc.

It all looks good on paper.....(famous last words).

I don't trust complications. This is one thing I feared and I was never wrong with my intuition on this.

When things got more complicated it sucks.

There is beauty in simplicity.

Reduced unsprung weight? Really?? Are they sure?
Del

I'll take one for the team.

I will allow them to send me some wheels to tinker with and a vehicle for some long term testing.

I won't even request much compensation.

Just regular per mile charges and basic travel / accommodation stuff.

I can't tell how many of those parts are moving... On the other hand, they have eliminated driveshafts, differentials, axles, universal/constant velocity joints, etc, not to mention all the moving parts of an ICE. Of course the same would be true of any in-wheel electric motor/brake system.

Now if they can really get a 50 hp motor in the wheel, and have it weigh less than a standard wheel, That is indeed noteworthy.

Somebody spent a lot of time creating the computer graphics! I'd much rather see actual video of a real vehicle traversing that kind of terrain. I don't see how that three-point wheel suspension could avoid contamination in that kind of terrain.

I didn't see any dust shields or grease/oil seals. I hope that the only way to keep the crap out, is not just to not use it at all.

No mounts either; where are the springs attached? I hope they don't claim there's no problems with unsprung weight because there IS NO load supported by the wheel.

They didn't even show that that test car even had those wheels on it. There was nothing to dispel the notion of a scam.

Makes you wonder what they're really selling.

Hasn't this already been done with motorcycle wheels?

I do see something I like about this approach and somethings I'm apprehensive about.

First, I like the multiple bearing supports that are not part of the electric motor shaft. This will significantly reduce the random loads experienced by the motor bearings and support. This will allow for a very small field gap inside the electric motor making for a higher efficiency in electromotive propulsion and potentially regenerative braking. Since they are presently using an electric motor designed for a motorcycle, a purpose built electric motor optimization may not have been performed.

I am apprehensive of the exposed gear teeth. Sandy grit, ice, braking dust and other debris will accelerate the wear and tear of these machined surfaces. For demonstration and proof of concept purposes the exposed gears do make sense. Enclosing the gearing mechanism may be tricky. Enclosing the gear drive might simply become the equivalent of an electric motor placed at the axis of rotation. I'm also apprehensive of switching to a much lower profile tire. With more "stuff" placed in the hub area more usable space is certainly needed but less shock absorbing pneumatic dampening to the whole wheel mechanism will also happen.

I do see something I like about this approach and somethings I'm apprehensive about.

First, I like the multiple bearing supports that are not part of the electric motor shaft. This will significantly reduce the random loads experienced by the motor bearings and support. This will allow for a very small field gap inside the electric motor making for a higher efficiency in electromotive propulsion and potentially regenerative braking. Since they are presently using an electric motor designed for a motorcycle, a purpose built electric motor optimization may not have been performed.

I am apprehensive of the exposed gear teeth. Sandy grit, ice, braking dust and other debris will accelerate the wear and tear of these machined surfaces. For demonstration and proof of concept purposes the exposed gears do make sense. Enclosing the gearing mechanism may be tricky. Enclosing the gear drive might simply become the equivalent of an electric motor placed at the axis of rotation. I'm also apprehensive of switching to a much lower profile tire. With more "stuff" placed in the hub area more usable space is certainly needed but less shock absorbing pneumatic dampening to the whole wheel mechanism will also happen.

its gonna be a bitch to change the tyre/tire (UK & USA spelling)
Then there's the training the tyre shop needs to work on these types of rims!

I didn't invent it, so I don't see much benefit in it....

Guys, it has to start somewhere. Isn't it obvious enough to you that our automotive leaders are not looking this direction. I trust you all watched 60 minutes last night and saw how far ahead of us China is, using our money I might add.

So this sort of development, just like Tesla, has to occur in this way.

Sure, if GM suddenly got off the oil companies tit and put the full force of their R&D behind this it would be refined and developed a lot faster than small, independent companies trying to get funding privately and all of the Fiskers who are taking full advantage of this situation to rip people off making serious R&D even harder to fund.

I say let them try.

Still better than dealing with the airlines!

Until it ''proves itself'' outdoors, it may only be durable enough for indoor driving...

Their web site had a video of a smaller car with the wheels on the rear, as many have noted. If they are correct regarding 19" tires and a 6.2:1 gear ratio, then the motor needs to be turning at about 6500 rpm to get 60 mph. That's a lot of rev's.

I wonder, on another tangent, if anyone is looking at using a linear induction motor on a ring set on the inner edge of the tire/rim, so the gears are eliminated?

--JMM

"... using a linear induction motor on a ring set ...."

.

When you warned us about a tangent, I wasn't expecting it to apply quite so literally.

I saw something like this proposed for an electric car prototype. They filled the whole inside of the wheel with the motor. The advantage was it's simplicity. The disadvantage was that the unsprung weight was prohibitively high. The Orbis concept is to shrink the motor and add gears for a net decrease in unsprung weight. I think the limit of this design will be the amount of heat dissipation available for that small motor generating high horsepower.

Sounds like it might be a good suggestion to mock-up a prototype for testing as a project for any one of the several posters who requested mechanical engineering project ideas...