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  (Source: cleanfuelconnectionnews.com)
Pre-production starts in early 2013 while full commercial production is set to begin in early 2014

A Michigan technology company has developed what could possibly be a new feature for electric vehicles (EVs) -- in-wheel electric motors.

Protean Electric, a Michigan-based tech company, is on its way to producing compact wheels for EVs that have electric motors inside of them instead of using conventional systems, which utilize larger motors to power a transmission or axles in order to move the wheels.

The in-wheel motors weigh 68 pounds and are 18 inches in diameter. They offer 110 HP and 598 lb-ft of torque. There is also a 24-inch version for more power.

The motors' anatomy consists of a permanent magnet at the center and the rotor on the outside for easy attachment to the wheels. Power electronics and inverters are located between these two, four to eight submotors make up the complete package. Typically, two to four of these complete motors are used on a vehicle.

The wheels can be used on either all-electric vehicles or hybrid plug-in vehicles. They are compact, lightweight wheels that can be used for retrofitting existing vehicles and for newly designed EVs as well.

Protean Electric received funding for the latest EV wheels from Chinese investor GSR Partners in the sum of $84 million. The wheels will be made in-house for now, but the company plans to eventually license the technology to larger manufacturers so they can be produced in higher numbers.

The motors will be built in a manufacturing center in Liyang, China, where the plan is to produce 50,000 motors per year. Pre-production starts in early 2013, while full commercial production is set to begin in early 2014.

Back in 2008, Michelin developed what it called the Active Wheel, which housed the motor, brake, and suspension inside the wheel.

Source: Protean Electric


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Unsprung Weight
By ChronoReverse on 7/20/2012 5:30:01 PM , Rating: 5
This has always been possible but unsprung weight is a Bad Thing (TM)




RE: Unsprung Weight
By cherrycoke on 7/20/2012 5:57:09 PM , Rating: 1
My thoughts exactly. I don't see any benefit of adding more weight to the wheels. The only way this kind of makes sense is the retro-fitting aspect. Older vehicles with heavy wheels (steel wheels) and not a lot of room for other configurations, this may be helpful but you still need room for the batteries.


RE: Unsprung Weight
By Stuka on 7/20/2012 8:19:10 PM , Rating: 4
Older vehicles can't accomodate the wheel size required. If the motor is 18", the wheel would have to be at least a 20" (bead diameter). So, we already rule out fleet vehicles, cargo vans, taxis, etc. We have now relegated the market to thugs and footballers.

Plus, as chrono stated... a live axle retrofitted with two 68lb motors, plus 20" wheels, plus the brakes.. we are talking a lot of unsprung weight, and all riding on 40-series tires... then trying to load a ton of cargo on top. The ride quality would be roughly equivalent to a covered wagon. lol

At best they've created a tractor propulsion system... incidentally, mining trucks already utilize this.. so really, they've created nothing that no one else has.


RE: Unsprung Weight
By blueaurora on 7/21/2012 11:15:18 AM , Rating: 1
To be honest this would likely lead to even lighter cards in general increasing efficacy as well as more balanced cars. With all the weight not being concentrated on the front. Could be a decent comproimise. I guess we won't know until we see a production unit designed around it.


RE: Unsprung Weight
By drycrust3 on 7/21/2012 5:23:09 PM , Rating: 4
The roughness of the ride is proportional to the ratio of sprung weight to unsprung weight. Because the motors are within the wheel then that adds to the unsprung weight, which increases the roughness of the ride.
Ride roughness isn't just about comfort for the passengers, it also becomes important regarding engine efficiency at speeds where the wheels loose contact or grip with the ground. The power gets fed to the wheel with the least grip, causing it to spin, meaning the other driving wheels loose power, meaning engine efficiency goes down.
Another factor is the use of gearing. This allows a motor to provide much higher torque to the wheels than itself is capable of producing. Of course, this is done with a sacrifice of speed. There is no mention of gearing within the wheel, which suggests the gearing is fixed. That means the motor within the wheel has a very limited range of capability. This might be acceptable on something like a bicycle, or a trailer, or somewhere that is flat and the load doesn't change much. Once you want to use the vehicle for a range of tasks or where the load on the motor changes a lot, then fixed gearing result in the motor working hard with little effect. In those situations the motor will need extra power capability e.g. from the rider or from the towing vehicle, or it will stall.


RE: Unsprung Weight
By DockScience on 7/22/2012 8:12:03 PM , Rating: 2
no gearing... direct 1:1 drive


RE: Unsprung Weight
By Gurthang on 7/23/2012 10:49:58 AM , Rating: 4
These are electric motors, I would assume you would have two to four of these on a vehicle using them, most likely a bus of some sort at those sizes. With full digital control of each motor you do not need brakes beyond some simple parking/hill/emergency break. I would also bet these are not your typical hobby motors, likely they are brushless and maybe even coreless so depending on how much copper and magents they use these should be fairly light. Typically the big issue with hub motors in real vehicles is that in order to make these motors efficient you need to reduce the gap between the coil and magnets as much as possible but the wheel body is always flexing with impact I don't care what you make it out of and making a motor body that can handle that while maintaining efficency is quite a challenge.

Also because it is an electric motor it has the same torque availible no matter the RPM so gearing is more about tuning the system (motor, battery, gears if any) to meet the torque and top speed requirements. In general so long as you don't need over 70 to 80 mph you can go with a single gear ratio or gearless in an electric drive with a 300 volt or higher power source.


RE: Unsprung Weight
By Souka on 7/23/2012 11:22:41 AM , Rating: 2
just seems bad...

68lbs added to wheel weight... saftey issue due to lost of handling.

Electric motor adds heat, blocks airflow, and/or reduces space available for larger brakes.

My $.02


RE: Unsprung Weight
By MrBlastman on 7/23/2012 12:56:25 PM , Rating: 2
Not to mention they are using permanent magnets in the wheels. Vibration and impact will denature/eliminate their ability to be magnetic over time.

Seems like a waste of money.


RE: Unsprung Weight
By drycrust3 on 7/23/2012 5:38:47 PM , Rating: 3
quote:
...most likely a bus of some sort...With full digital control of each motor you do not need brakes beyond some simple parking/hill/emergency break.

I am a bus driver, and I can assure you this isn't suitable for a bus, at least on its own anyway.
If you look at the hubs of a bus you'll notice that they have a sort of baked on grime appearance, and even in the wet weather they are dry. This is because of the heat generated by the brakes every time the bus slows down. Take any bus, fill it up to the legal maximum, then drive it at the legal speed limit down the steepest hill on any bus route in your city, and those brakes not only HAVE to work, but the heat generated has to be dissipated (which is why they use air brakes and not hydraulic).
If you used the motors to generate electricity, then where do you want the electricity to go? A giant resistor? And what happens if there is some sort of component or electrical failure? Will the bus stop of its own accord? What happens if the bus is driven through a large puddle of water? Will the brakes still work? What if the driver hits a kerb or pot hole? Can the motor handle starting the bus on the steepest hill on the bus route with a full standing load?
Can the bus still do the sharp turn needed to pull out from behind another bus at a busy bus stop? Can the driver still do a nice smooth braking as he pulls into a bus stop? Can the bus be towed away if there is a serious breakdown of some sort?
These are only a few of the really serious questions that would be asked before anyone would get on board such a bus.


RE: Unsprung Weight
By mattclary on 7/20/2012 10:07:55 PM , Rating: 5
RE: Unsprung Weight
By Etsp on 7/22/2012 3:22:39 PM , Rating: 3
Interesting article.

The facts that they presented were:
There were perceptible differences in driving performance between the unsprung ballast and the sprung ballast.

The sprung ballast had better performance than the unsprung ballast.

That was the extent of the facts of that article. Everything else was opinion, and it was the opinion of those developing in-wheel powertrain tech.

Their opinion:
The extent of the differences were "minor" and could be "mitigated"

The article had no detail on what the differences were, how perceptible they were, and how they could be mitigated.

My opinion on the in-wheel powertrain tech: "Needs more data"


RE: Unsprung Weight
By PaFromFL on 7/21/2012 9:43:05 AM , Rating: 2
An active suspension with road height sensing/prediction could compensate for unsprung weight, and get rid of some traditional suspension components. Using mechanical linkages and hydraulic dampers for suspension makes as much sense as using 2nd millennium carburetors on engines.

Electronics can simplify car design while improving performance and efficiency. With the space savings of hub motors and an electric suspension, engineers could more easily optimize aerodynamics and passenger/cargo configurations.


RE: Unsprung Weight
By spread on 7/21/2012 2:25:49 PM , Rating: 2
True, but combined with something like a tweel, I imagine the weight gain wouldn't be very much at all. And you gain a significant amount of passenger or luggage space.


RE: Unsprung Weight
By inperfectdarkness on 7/23/2012 1:38:41 AM , Rating: 2
There's a reason Lotus got the idea to put disc-brakes inboard, close to centerline on its racing cars...way back in the 1950's. Ideally, you want to put as much of a car's mass as possible roughly centered inside the wheelbase (front to back and side-side). This configuration offers the greatest stability.

Just for the sake of comparison, the Unsprung : Sprung ratio is roughly a factor of 10:1. This means that if you add 68 lbs sprung mass to each wheel (68 x 4) you've essentially added as much as putting 2720 lbs inside the passenger compartment--nearly 2 and 1/2 tons. Go drive a car that weighs 3000 lbs and then drive one that weighs 4700 lbs and you'll certainly know the difference.


RE: Unsprung Weight
By joos2000 on 7/23/2012 7:11:30 PM , Rating: 2
Not to mention unfiltered bumps and vibrations straight into high precision equipment.

Unless we resurface all our roads to be super smooth, this tech is pretty much infeasible.


Nothing new there
By mrplowking on 7/20/2012 4:45:47 PM , Rating: 5
That technology is almost 20 years old :

http://en.wikipedia.org/wiki/TM4_Electrodynamic_Sy...




RE: Nothing new there
By foolsgambit11 on 7/20/2012 8:37:43 PM , Rating: 2
More than that. I have a 1950's Popular Science magazine that has an article about a military vehicle (maybe a 5 ton?) outfitted with a wheel in each hub. I guess this is smaller, but the concept is ancient. Incidentally, the feature article for that edition was how they make those new-fangled transistors.


RE: Nothing new there
By foolsgambit11 on 7/20/2012 8:42:58 PM , Rating: 5
Oops, I was way off. It was 1966. Here's the online archive of that story. http://www.popsci.com/archive-viewer?id=1SkDAAAAMB...


RE: Nothing new there
By Ringold on 7/21/2012 2:08:17 PM , Rating: 2
Amazing how little certain fields have advanced, in some respects, in half a century.

http://tech.fortune.cnn.com/2012/07/17/thiel-vs-sc...

Thiel's argument, explained more at length in different places, has some holes, but has a kernel of truth. Huge leaps in some narrow places still occurring all the same, but look at a home, for example. All the major appliances were invented and adopted widely by the 50s and 60s. A refrigerator was a quantum leap in terms of storing food in the home. Automatic crushed ice dispenser with LED lighting, not so much.

Of course they're much more affordable now then at first, lots of little holes in the argument, but like this in-wheel tech, little is new.


RE: Nothing new there
By jharper12 on 7/22/2012 8:09:51 AM , Rating: 2
It's funny you should mention this. When I first read the article I thought, "EV manufacturers spend a lot on reducing wheel weight... no market there, but I would love to put two big motors on the back wheels of a deuce and a half for starting down the road!"

Yep... really want to build a hybrid deuce now... may need to set about doing so.


RE: Nothing new there
By Bad-Karma on 7/22/2012 10:24:43 AM , Rating: 2
Why set your sights so low with a Deuce....Go for a HEMTT!


RE: Nothing new there
By DennisB on 7/23/2012 12:56:31 PM , Rating: 2
If you want light but highly efficient wheels the australian company CSIRO has been leading for ages.
http://www.csiro.au/Outcomes/Energy/Powering-Trans...

This here is about high power, but I doubt for any serious uses beyond cars and vans.


30% Economy Improvements?
By WalksTheWalk on 7/20/2012 5:27:41 PM , Rating: 2
I question their claim of a possible 30% improvement in efficiency. That seems like marketing claims to me instead of real world gains.

It seems like the main efficiency here might be a little weight loss, reduction of some heat loss in the drive train and greater regenerative braking efficiency. I recall that the Nissan Leaf has 75% regenerative braking efficiency, so their claim of 85% doesn't seem like much of a jump.




RE: 30% Economy Improvements?
By zozzlhandler on 7/21/2012 5:13:44 PM , Rating: 2
Losses in the drive chain are *very* substantial. Remember, you have a gearbox (maybe), a universal joint and a differential. Theses add up to 30% easily.


RE: 30% Economy Improvements?
By Alexvrb on 7/22/2012 1:35:11 AM , Rating: 2
Substantial, yes. But actually typical drivetrain losses in a remotely modern vehicle are more like ~20% or so going from the flywheel to the driven wheels. But that's with a conventional vehicle with a conventional transmission/transaxle.

If you want to compare apples to apples, compare this unsprung wheel-motor to an electric motor mounted elsewhere, driving the wheels via a fixed ratio transmission. I suspect their comparison doesn't look so awesome against an existing EV like that.

Not to mention what unsprung weight does to your acceleration. Even the Prius and Leaf drivers will be riding your butt on the onramp. Yikes!


RE: 30% Economy Improvements?
By FITCamaro on 7/22/2012 8:51:19 PM , Rating: 2
Losses with a manual transmission are only around 15% generally.


RE: 30% Economy Improvements?
By SunLord on 7/23/2012 4:13:22 PM , Rating: 2
I doubt you can get an electric car with a manual...


RE: 30% Economy Improvements?
By Fritzr on 7/21/2012 8:41:21 PM , Rating: 2
The efficiency improvement is quite reasonable. The only reason all wheel drive designs use a motor attached to the chassis driving the wheel with a shaft is to keep the weight of the motor on the sprung side of the suspension.

*Bad Things* occur when you increase the weight hung off the end of the springs (unsprung weight). There are also some axle designs that improve power efficiency that are unusable because they increase the unsprung weight of the axle assembly.

Hub motors have been available for quite a few years now. They are the pancake motors used on bicycles. Individual wheel drive for cars and trucks has been announced often over the years. So why this is a major innovation is a mystery.


RE: 30% Economy Improvements?
By Fritzr on 7/21/2012 8:45:46 PM , Rating: 2
At the end of the article there is a link to an older story about Michelin's version of this idea in 2008. I am sure Michelin had a good reason for abandoning the idea.


Made in china
By mchentz on 7/20/2012 6:06:11 PM , Rating: 4
Developed in the US then being made in china. what a shame.




RE: Made in china
By blueaurora on 7/21/2012 11:22:46 AM , Rating: 3
Paid for by the Chinese developed in the US and then shipped back to china. If we funded it we might have made it. Why can't we fund development for these ourselves? Big oil runs the US car industry and no one can take a large scale risk or they go under.


RE: Made in china
By Ringold on 7/21/2012 3:32:18 PM , Rating: 2
Right. Exxon is totally keeping Tesla down.

And Monsanto GM seed is going to cause our babies to grow 3 heads.

And don't even get me started about those fake lunar landings!


RE: Made in china
By FaaR on 7/22/2012 11:21:05 AM , Rating: 3
Exxon (well, Big Oil in general, actually) aren't spending a lot of effort hindering Tesla specifically because that company's such a marginal, small-time player in the market. They ARE however spending a LOT of dough poo-pooing alternative energy in general (and lobbying for fossile fuel use). This is well known.

Monsanto seeds may not cause babies to grow two extra heads, but there's certainly enough legitimate reasons to hate on that company. Monsanto is the devil, basically. All of their company directors should be lined up and executed by firing squad for crimes against humanity.

Also, no sane person believe the moon landings were faked so please don't bring up that nonsense in a serious discussion, unless your aim is to make yourself look foolish...


RE: Made in china
By MrMaringer on 7/23/2012 11:39:14 AM , Rating: 2
Actually, developed in the UK by a company called PML Flightlink, though Protean's headquarters is now in the US.

In-wheel motors certainly sound like an elegant solution to me though I don't have the engineering chops to deal with the whole unsprung weight argument.

I suppose what counts is whether or not the benefits of the technology outweigh any problems. The proof will be in the pudding.


Flat tyre
By macca007 on 7/20/2012 10:42:26 PM , Rating: 2
So your Missus goes shopping and gets a flat tyre, 30kg to try and lift off and change over, I think there might be a lot of back compo's happening soon!
Hell 30kg's is pretty heavy even for a bloke, Not so much the weight it's how friggin large and awkward it is to lift up and put on, Will now be even worse with 30kg+ wheels.
I think they might need to go into partnership with Michilin's "Tweel" so no more flat tyres in the first place. ;)




RE: Flat tyre
By Thalyn on 7/21/2012 1:54:02 AM , Rating: 3
Not necessarily.

Fitting the motor as the hub, to which the wheel then bolts, would allow the use of standard (albeit large) wheels without adding unnecessary complications to the typical roadside tyre change.

It would also make it a LOT harder for someone to come along and steal all your engines, too. You don't often hear of people returning to cars without hubs, but there's plenty of stories about wheels going missing.


RE: Flat tyre
By Gondor on 7/21/2012 3:37:48 PM , Rating: 3
I'm sure this can be worked around ... Perhaps a combination of run-flat tire with foam filling instead of air (the stuff some smaller cars come with nowadays in place of the spare tire, a can of foam that you use to fill the punctured tire with).

But as others have pointed out, this is hardly a new technology. Why not make an article about a company inventing minimalistic black rectangle ? Oh, wait ...


By v3rlon on 7/24/2012 8:15:56 AM , Rating: 3
If you look at the image, this system replaces your existing rims at that 68 pound weight mark. Now, if you drive a decent sports car, you might have 24-25 pound rims, but everyone else is likely looking at something a bit heavier. If you have some of those tacky giant rims (and you didn't spend $2500 on the set), you might already have a set of 50 pound rims. I don't believe these things will be going in the next Corvette, 911, or 400Z. They also might lose some weight as they are further developed.

An obvious advantage here is that you could put batteries where the electric motor was and not lose trunk space.

The average driver isn't going to see that much difference and ride quality certainly wont be "like a covered wagon."

To the Bus driver: dynamic electric brakes do a fine job of stopping a train. I am sure they can stop a bus if designed to do so. In an electric vehicle, the logical place to put the electricity is back into the batteries (like on hybrids now using regenerative braking).

Low end torque on an electric motor makes a diesel look like a chipmunk and ball bearing treadmill. Again, see trains. Assuming you put the right wheels on your bus, it should be able to handle your environment. Use the right tool for the job, of course.




stuff like this already exists.
By zephyrprime on 7/23/2012 5:07:22 PM , Rating: 2
Stuff like this already exists. However, the increase in efficiency due to fewer linkages is probably not worth the greater amount of unsprung mass and lower reliability due to the motor being jolted so often by road bumps.




in wheel electric motors
By Richard875yh5 on 7/26/2012 6:22:36 PM , Rating: 2
This idea has many drawbacks and I can not see it ever becoming feasible. Permanent magnets don't like jolts and will fail. And someone mention unsprung wheels is a major problems. I'm sure all the EV manufacturers have look at that idea and chose not to go that route.




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