TM4 receives $3,7M to develop new powertrain technologies

[Doctorbass]

TM4 receives $3,7M to develop new powertrain technologies http://bit.ly/1zjb1LX

http://news.gc.ca/web/article-en.do?mthd=tp&crtr.page=1&nid=933519&crtr.tp1D=930


Research and Development (R&D) Projects

Low Cost Wheel Motors for Electric and Hybrid Vehicles
Lead Proponent: TM4 Inc.
Location: Montréal, Québec
Funding: $3,744,768

The objective of this project is to design an in-wheel motor electric drive system for electric vehicles, with one of the highest power densities in the world, and at the lowest possible cost. This system will consist of one or more power converters and electric machines, to be assembled and bench tested, and then tested on the road in an electric vehicle. Several experimental prototypes of engine and electronic power subcomponents will use innovative materials and/or concepts. This project will allow an entire chain of expert Canadian suppliers to take part in the development and eventual commercialization of this new innovative powertrain topology.

Doc

 

[Punx0r]

Light, powerful and cheap? They have an uphill task...

 

[major]

History repeating, again.
http://www.tm4.com/about-us/history/
What's different now than 25 years ago? More money :lol:

 

[okashira]

Ugh, say NO to wheel motors for EV's. Why do people keep thinking this is a good idea?
Automakers work so hard to reduce sprung weight so why throw a motor on there?
If for some reason you want a motor per each wheel for some super advanced torque vectoring, then mount them in the middle and use axles.

If they could get the motor to ~7lbs, it would be fine, but that's not happening until they can also make them 99.4% efficient across the powerband too.

 

[Punx0r]

Hub motors do make a lot of sense from a cost, packaging and efficiency perspective.

 

[liveforphysics]

Ugh, say NO to wheel motors for EV's. Why do people keep thinking this is a good idea?
Automakers work so hard to reduce sprung weight so why throw a motor on there?
If for some reason you want a motor per each wheel for some super advanced torque vectoring, then mount them in the middle and use axles.

If they could get the motor to ~7lbs, it would be fine, but that's not happening until they can also make them 99.4% efficient across the powerband too.

If you prioritize efficiency, durability, simplicity, and low cost, you won't beat hubmotors.

With respect to the unsprung weight, it's not that you can't make a vehicles suspension work extremely well with heavy wheels, it just requires adequate damping. The 3ft suspension travel desert trucks run a very hefty wheel/tire combo, and still have suspension that works at 150mph through rough terrain.

When designing a vehicle to transport people and goods, unsprung mass is rightly extremely low on the priority list. If you have a car with poor suspension, and you lighten the wheels, it works better, no disagreement. However, I doubt more than a couple folks on this entire board could notice, even on a racetrack. I know shaving 10lbs off each wheel on my racecar was undectable anywhere aside from my wallet being lighter.

The object is ultimately to turn the wheel. Systems that add axles and gearing stages and whatnot are just adding complexity inefficiency and failure modes in exchange for what amounts to no advantage in almost all applications outside of track cars.

 

[Punx0r]

With good design the structure of the hub motor would replace some parts of the existing hubs on the car, like the bearing(s), knuckle/upright, CV joint, driveshaft. The suspension could pick up straight from the motor casing. The wheel could be centreless - just a rim with tabs that bolts straight to the motor case. What I'm trying to say is that it's not a case of adding the weight of a hubmotor to the weight of all the suspension that's already there on a conventional car. The extra weight of a hubmotor design might not be that great.

The confounding thing is the need to retain a mechanical brake. This still requires the weight of a disc, calliper and carrier. Regen braking might mean they can be reduced in size but they still need to large enough to stop the car from top speed.

 

[flathill]

Even if you use a fully active suspension to increase comfort your actuators have to be beefed up significantly to handle the additional mass of the hub motor.

That said I've driven a "pro touring" hot rod with 200 pound ford 9" rear end that handled surprisingly well and was rather comfortable due to the long wheelbase. For the vast majority of vehicles hub motors may be the future, simply because they free up more room for cargo and allow for more platforms. I think we are also going to see a return to fatter sidewalls.

Even if we don't go full active with actuators we can use http://en.wikipedia.org/wiki/Magnetorheological_damper

combined with lookahead road sensing/knowing

 

[okashira]

With good design the structure of the hub motor would replace some parts of the existing hubs on the car, like the bearing(s), knuckle/upright, CV joint, driveshaft. The suspension could pick up straight from the motor casing. The wheel could be centreless - just a rim with tabs that bolts straight to the motor case. What I'm trying to say is that it's not a case of adding the weight of a hubmotor to the weight of all the suspension that's already there on a conventional car. The extra weight of a hubmotor design might not be that great.

The confounding thing is the need to retain a mechanical brake. This still requires the weight of a disc, calliper and carrier. Regen braking might mean they can be reduced in size but they still need to large enough to stop the car from top speed.

I'd hope so. But the problem is their IN-efficiency. by their nature, they need to be high torque, low RPM. You end up with the same problem as hub motors on e-bikes. Their inefficient and heavy. Electric motors need high RPM to provide the best efficiency per weight specific power.
So you have 4 hub motors to make up for their low torque. Are you really saving money at that point? A single motor with a inexperience differential will still win, IMO.
It might make sense for a 4wd car, four small hub motors. But such a car would still excess sprung mass.

The knuckle/upright would certainrty be integrated with the hub motor, but replacing a driveshaft and axles wont save unsprung weight. (well, the axles will, by a small amount.)


On the brake idea, this is the only way I can see it happening for any kind of performance car. If they can eliminate the friction brakes altogether, such as by discharging to resistors heatsinked to the chassis or the water cooling system, but that would be pretty far off.

 

[Doctorbass]

TM4 is the company that had Pierre Couture,

our Quebec inventor of the car wheel motor back in 1992.

That motor had 1200NM torque and had his incorporated controller inside the wheel. It had financing from Hydro Quebec He already knew that there was huge potential.. but H-Q closed the project and all the assiciated patent was left on a desk taking dust for years...

jump at 7:05:

[youtube]jHmxJPTWD-M[/youtube]

Doc

 

[flathill]

Electric wheel motors were developed in the late 1800s

Hydro quebec seems always seems to fcuk stuff up.....patent encumbrance

They stiffled the development of iron phoshate cells, lithium metal cells, and hub motors.

--------

1996
John B. Goodenough and his team patent lithium metal phosphate cathode at UT (university of texas)

1997
Hydro-Québec obtains an exclusive license on Goodenough‘s invention from UT

In the patent lawsuits in the US in 2005 and 2006, UT and Hydro-Québec claimed that every battery using LiFePO4 as the cathode and the cathode material used in some lithium ion batteries infringed their patents,

---

With lithium metal ploymer cells they licensed the tech to some royal french family (of rolling paper fame) who has more or less sat on it

Vincent Bolloré, the French industrialist and corporate raider, is a major investor in Pininfarina, the maker of the B0 (B Zero) all-electric car. The company unveiled the B0 at the 2008 Paris Motor Show, where the government failed to release the Syrota report. Bolloré’s industrial conglomerate also owns a battery business.

Aerospace tycoon Serge Dassault and his family have an estimated net worth of more than US $6 billion. The French government recently awarded Dassault Aviation the sole contract to develop a military fighter drone. In 2003, Groupe Dassault, along with Hydro-Québec and Groupe Heuliez, announced plans to mass-market electric vehicles. Mr. Dassault said, “We are very confident we will succeed in implementing an electric vehicle in Europe.”

The lithium-metal-polymer (LMP) batteries produced at the plant were developed by researchers at Hydro-Québec and the University of Texas. Bolloré Group acquired the Boucherville plant and the rights to the LMP technology in 2007 in the wake of Avestor’s bankruptcy filing. Shortly thereafter, bankruptcy trustee RSM Richter sold the company to Bolloré for an estimated $15 million.

Notice a trend?
-----

With hub motors I dont know but it doesnt surprise me they had a high torque motor topology back in 1992 and did nothing with it. It seems they stalled the development of all outrunner type hub motors with built in controllers

Update:
Dassalt connection

The heir to the Couture wheel motor is now marketed by TM4, a subsidiary that has made deals with France's Dassault

Unfortunately, in 1995 Hydro-Quebec has taken a completely incomprehensible decision to significantly reduce its proposed development of Couture’s power train, which led to the resignation of its inventor in 1995. Pierre Couture has never worked on this project since. The TM4 company, a subsidiary of Hydro-Québec, which was set up to commercialize the Couture power train with 4 wheel-motors, hence its name (Technology Motor 4 “wheels”), has stopped working on the high power wheel-motor for all practical purposes and works now mainly on central electric motors, like everyone else.

 

[flathill]

This is why this technology was so valuable. They were granted this super broad claim:

2. An electrically motorized wheel assembly according to claim 1, wherein:
said stator is provided with a hollow portion; and
said power electronics are fixedly mounted within said hollow portion.

6. An assembly according to claim 5, wherein said converting means comprises:
a DC/AC converter having an input for receiving a direct current from said input terminals, and three outputs for generating three phase AC currents into said output terminals; and
a microprocessor unit connected to said converter for controlling its operation.

---

Any outrunner hub motor with a built in controller is subject to their claim! There is huge copper savings from in hub controllers when you are talking about phase wires large enough to generate 1200nm or torque using a safe system voltage.


"With this outer-rotor type motor wheel, a converter has to be provided. This converter is mounted inside the vehicule and can be very cumbersome. Such high current circulating through the power line produces heat which is energy loss and also requires a power line which can be quite heavy."

 

[liveforphysics]

With good design the structure of the hub motor would replace some parts of the existing hubs on the car, like the bearing(s), knuckle/upright, CV joint, driveshaft. The suspension could pick up straight from the motor casing. The wheel could be centreless - just a rim with tabs that bolts straight to the motor case. What I'm trying to say is that it's not a case of adding the weight of a hubmotor to the weight of all the suspension that's already there on a conventional car. The extra weight of a hubmotor design might not be that great.

The confounding thing is the need to retain a mechanical brake. This still requires the weight of a disc, calliper and carrier. Regen braking might mean they can be reduced in size but they still need to large enough to stop the car from top speed.

I'd hope so. But the problem is their IN-efficiency. by their nature, they need to be high torque, low RPM. You end up with the same problem as hub motors on e-bikes. Their inefficient and heavy. Electric motors need high RPM to provide the best efficiency per weight specific power.
So you have 4 hub motors to make up for their low torque. Are you really saving money at that point? A single motor with a inexperience differential will still win, IMO.
It might make sense for a 4wd car, four small hub motors. But such a car would still excess sprung mass.

The knuckle/upright would certainrty be integrated with the hub motor, but replacing a driveshaft and axles wont save unsprung weight. (well, the axles will, by a small amount.)


On the brake idea, this is the only way I can see it happening for any kind of performance car. If they can eliminate the friction brakes altogether, such as by discharging to resistors heatsinked to the chassis or the water cooling system, but that would be pretty far off.

When starting from the medium of electricity, one is only as confined in the conversion process to torque as the limits on their creativity in motor design.

You can have very low RPM and very high efficiency, look at direct-drive 4MW 96% efficient wind turbines running at 20RPM.

It's not a weight penalty either if designed well. When starting from combustion, it's a tremendous penalty in power density to decrease in RPM.

The thermodynamic optimization is always to leverage motor geometry to accomplish the creation of torque. All options that involve intermediate power transfer stages also involve unnecessary additional losses.

Some small scale examples:
https://www.thingap.com

 

[Punx0r]

I think mechanical brakes will always be required on safety grounds, like it's a legal requirement to have mechanical steering.

A driveshaft with CV joint on each end is reasonably heavy, easily 15-20 kg IME.

 

[flathill]

Large scale thin gap motor but with proper litz wire and opposed mags

https://www.navalengineers.org/ProceedingsDocs/EMTS2014/Presentations/Wright_4.pdf

2.66 x 10^5 foot pounds of torque
93% efficient at full torque at 120rpm

 

[okashira]

Large scale thin gap motor but with proper litz wire and opposed mags

https://www.navalengineers.org/ProceedingsDocs/EMTS2014/Presentations/Wright_4.pdf

2.66 x 10^5 foot pounds of torque
93% efficient at full torque at 120rpm

1.6 LB/hp
And that's for a state of the art, weight minimized design. A model S motor would weigh 750lb! (they are really ~70 lb?)
You guys are proving my point for me :-D.

Fact is, high torque requires size. Sure , you can make a bad ass design, use carbon fiber, trusses, air gaps, whatever, but at the end of the day a high torque motor at the same power level as a low torque motor, with equally advanced design, is going to require more size and weight.

On the wind turbine example, another point made for me... I am sure it's weight specific power is also not competitive.

 

[Doctorbass]

Large scale thin gap motor but with proper litz wire and opposed mags

https://www.navalengineers.org/ProceedingsDocs/EMTS2014/Presentations/Wright_4.pdf

2.66 x 10^5 foot pounds of torque
93% efficient at full torque at 120rpm

Oh Jeezz!!
Finally someone is talking about famous Litz wires!! I searched alot about that in the last week o the forum to build my charging 3kW coil for the Adaptto.... and nobody really expressed they even know their existence! lol

 

[flathill]

Large scale thin gap motor but with proper litz wire and opposed mags

https://www.navalengineers.org/ProceedingsDocs/EMTS2014/Presentations/Wright_4.pdf

2.66 x 10^5 foot pounds of torque
93% efficient at full torque at 120rpm

1.6 LB/hp
And that's for a state of the art, weight minimized design. A model S motor would weigh 750lb! (they are really ~70 lb?)
You guys are proving my point for me :-D.

Fact is, high torque requires size. Sure , you can make a bad ass design, use carbon fiber, trusses, air gaps, whatever, but at the end of the day a high torque motor at the same power level as a low torque motor, with equally advanced design, is going to require more size and weight.

On the wind turbine example, another point made for me... I am sure it's weight specific power is also not competitive.

We are talking torque density not power density. These opposed magnet permanent magnet motors have over 30 foot pounds or torque per pound. A liquid cooled model S motor is much larger weighs near a hundred pounds (it is the air cooled roadster motor that weighs 70 pounds) which means its torque density is only 4 foot pounds of torque per pound (using P85 443 foot pound figure). Also note the the P85 motor is putting out 443 foot pounds of torque it's efficiency no where close to 93%. Induction motor suck with regards to torque density but you can spin them fast. We are talking direct drive wheel motors here, not motors attached to gearboxes, but note the motor with the highest power density (aircooled) in the world is also a ironless motor with litz wires and permanent magnets and makes 5hp per pound WITH 95% efficiency at 8400 rpm

 

[okashira]

Large scale thin gap motor but with proper litz wire and opposed mags

https://www.navalengineers.org/ProceedingsDocs/EMTS2014/Presentations/Wright_4.pdf

2.66 x 10^5 foot pounds of torque
93% efficient at full torque at 120rpm

1.6 LB/hp
And that's for a state of the art, weight minimized design. A model S motor would weigh 750lb! (they are really ~70 lb?)
You guys are proving my point for me :-D.

Fact is, high torque requires size. Sure , you can make a bad ass design, use carbon fiber, trusses, air gaps, whatever, but at the end of the day a high torque motor at the same power level as a low torque motor, with equally advanced design, is going to require more size and weight.

On the wind turbine example, another point made for me... I am sure it's weight specific power is also not competitive.

We are talking torque density not power density. These opposed magnet permanent magnet motors have over 30 foot pounds or torque per pound. A liquid cooled model S motor is much larger weighs near a hundred pounds (it is the air cooled roadster motor that weighs 70 pounds) which means its torque density is only 4 foot pounds of torque per pound (using P85 443 foot pound figure). Also note the the P85 motor is putting out 443 foot pounds of torque it's efficiency no where close to 93%. Induction motor suck with regards to torque density but you can spin them fast. We are talking direct drive wheel motors here, not motors attached to gearboxes, but note the motor with the highest power density (aircooled) in the world is also a ironless motor with litz wires and permanent magnets and makes 5hp per pound WITH 95% efficiency at 8400 rpm

Even 30 ft-lb per pound is not really good enough. For good acceleration, you'll need 2000ft-lbs or more on a car that's anything better then an econo-box. That would be 66lbs of weight on the wheels - too much for any kind of performance car. I suppose it could work for an economy car. They will want to use large sidewall tires to mitigate loss off effectiveness of the suspension performance due to the 40lbs of motor hanging on two wheels (I doubt you'd get that good of weight specific torque on a smaller motor due to manufacturing reasons.... you won't be able to scale down the material wall thicknesses and the intricately layed out wire and magnets) the motor you are looking at is massive.
I suppose if you only need 1000ft-lb... 0.3 G off the line is acceptable for an economy car.

 

[Punx0r]

Do you really consider 66lb (30kg) spread between four wheels is excessive? Even between two that's just fine by me. I'm pretty confident the driveshafts on my FWD car weigh 25-30kg combined.

I suspect there is a lot more unsprung mass on an average car than you realise!

 

[okashira]

Do you really consider 66lb (30kg) spread between four wheels is excessive? Even between two that's just fine by me. I'm pretty confident the driveshafts on my FWD car weigh 25-30kg combined.

I suspect there is a lot more unsprung mass on an average car than you realise!

Well, axles only partially contribute to sprung weight. Yeah, 66lb might be OK if everything else is optimized, and they can reduce brake size by using regen.
Id guess at ~50lbs per wheel sprung weight on a performance car.
The problem is I doubt you could get 2000ftlb from a 66lb motor, let alone 500ftlb from a 16.5lb motor, unless you are cooling the windings with liquid nitrogen! :-D

 

[liveforphysics]

Do you really consider 66lb (30kg) spread between four wheels is excessive? Even between two that's just fine by me. I'm pretty confident the driveshafts on my FWD car weigh 25-30kg combined.

I suspect there is a lot more unsprung mass on an average car than you realise!

Well, axles only partially contribute to sprung weight. Yeah, 66lb might be OK if everything else is optimized, and they can reduce brake size by using regen.
Id guess at ~50lbs per wheel sprung weight on a performance car.
The problem is I doubt you could get 2000ftlb from a 66lb motor, let alone 500ftlb from a 16.5lb motor, unless you are cooling the windings with liquid nitrogen! :-D

Because you don't know how to make the torque you are rightly not leading the motor development.

This fortunately has no impact on folks who do have the skills from developing them.

 

[flathill]

Even 30 ft-lb per pound is not really good enough. For good acceleration, you'll need 2000ft-lbs or more on a car that's anything better then an econo-box. That would be 66lbs of weight on the wheels - too much for any kind of performance car. I suppose it could work for an economy car. They will want to use large sidewall tires to mitigate loss off effectiveness of the suspension performance due to the 40lbs of motor hanging on two wheels (I doubt you'd get that good of weight specific torque on a smaller motor due to manufacturing reasons.... you won't be able to scale down the material wall thicknesses and the intricately layed out wire and magnets) the motor you are looking at is massive.
I suppose if you only need 1000ft-lb... 0.3 G off the line is acceptable for an economy car.

What are you talking about? The 1992 TM4 motor produced 1200 Nm (885 foot pounds) of torque per wheel. 4 of those motors (4800 Nm) accelerated the large steel Chrysler Intrepid 0-60 in just over 3 seconds. Why do you think the project was canceled, because it didn't work? It was cancelled because it worked too well. GM realized the same thing. Remember GM/Magnequench invented the modern sintered neo magnet. At the same time the TM4 motor (which torque density was enabled by sintered neo) was cancelled, GM sold Magnequench

TM4=Technology Motor 4 “wheels”

So when GM put Magnequench on the block in 1995, who should come up with the $70 million asking price?[7] An investment consortium headed by Archibald Cox Jr. (son of the illustrious Watergate prosecutor) acting in concert with two Chinese state-owned metals firms, San Huan New Material and China National Nonferrous Metals Import and Export Company (CNNMIEC), which had been pestering GM to sell Magnequench since 1993.[8]

In the deal, the two Chinese firms took at least a 62 percent majority of Magnequench shares, with the senior Chinese investor taking over as the company's chairman and Cox as chief executive officer (CEO).[9] (In 2005, when Magnequench merged with a Canadian firm then known as AMR, Cox was listed as owning a significant minority share of AMR and was named AMR chairman.[10] )

The chairman of San Huan, a Mr. Zhang Hong, son-in-law of former Chinese "paramount leader" Deng Xiaoping (and now director of the Research and Development Bureau of the Chinese Academy of Sciences[11]), took over as chairman of Magnequench.[12] No doubt, Mr. Zhang's desire to acquire Magnequench was informed by the Chinese government's-and his father-in-law's-"Super 863 Program" to develop and acquire cutting-edge technologies for military applications, including "exotic materials."[13] The other Chinese investor in Magnequench, CNNMIEC, was at the time run by yet another Deng Xiao-ping son-in-law.

CFIUS's Role in Magnequench
But the United States government surely would not permit the Chinese simply to walk in and take over a significant U.S. high-tech firm, would it? Several sources indicate that CFIUS did reach a "mitigating agreement"[14] with Magnequench's new owners that the Chinese companies could not remove Magnequench's production equipment or jobs from the U.S. for a period of ten years.[15]

It is, however, an old Chinese tradition that "rules are made to be broken" (shang you zhengce, xia you duice). Magnequench's Chinese owners cleverly reinterpreted the CFIUS conditions. One Magnequench employee reported that shortly after the Chinese took over, Magnequench's neodymium-iron-boron magnet production line was "duplicated in China" and that, after the Chinese "made sure that it worked, they shut down" the U.S. production in Indiana. The employee added, "I believe the Chinese entity wanted to shut the plant down from the beginning. They are rapidly pursuing this technology."[16]

 

[okashira]

Even 30 ft-lb per pound is not really good enough. For good acceleration, you'll need 2000ft-lbs or more on a car that's anything better then an econo-box. That would be 66lbs of weight on the wheels - too much for any kind of performance car. I suppose it could work for an economy car. They will want to use large sidewall tires to mitigate loss off effectiveness of the suspension performance due to the 40lbs of motor hanging on two wheels (I doubt you'd get that good of weight specific torque on a smaller motor due to manufacturing reasons.... you won't be able to scale down the material wall thicknesses and the intricately layed out wire and magnets) the motor you are looking at is massive.
I suppose if you only need 1000ft-lb... 0.3 G off the line is acceptable for an economy car.

What are you talking about? The 1992 TM4 motor produced 1200 Nm (885 foot pounds) of torque per wheel. 4 of those motors (4800 Nm) accelerated the large steel Chrysler Intrepid 0-60 in just over 3 seconds. Why do you think the project was canceled, because it didn't work? It was cancelled because it worked too well. GM realized the same thing. Remember GM/Magnequench invented sintered neo magnets. At the same time the TM4 motor was cancelled GM sold Magnequench

So when GM put Magnequench on the block in 1995, who should come up with the $70 million asking price?[7] An investment consortium headed by Archibald Cox Jr. (son of the illustrious Watergate prosecutor) acting in concert with two Chinese state-owned metals firms, San Huan New Material and China National Nonferrous Metals Import and Export Company (CNNMIEC), which had been pestering GM to sell Magnequench since 1993.[8]

In the deal, the two Chinese firms took at least a 62 percent majority of Magnequench shares, with the senior Chinese investor taking over as the company's chairman and Cox as chief executive officer (CEO).[9] (In 2005, when Magnequench merged with a Canadian firm then known as AMR, Cox was listed as owning a significant minority share of AMR and was named AMR chairman.[10] )

The chairman of San Huan, a Mr. Zhang Hong, son-in-law of former Chinese "paramount leader" Deng Xiaoping (and now director of the Research and Development Bureau of the Chinese Academy of Sciences[11]), took over as chairman of Magnequench.[12] No doubt, Mr. Zhang's desire to acquire Magnequench was informed by the Chinese government's-and his father-in-law's-"Super 863 Program" to develop and acquire cutting-edge technologies for military applications, including "exotic materials."[13] The other Chinese investor in Magnequench, CNNMIEC, was at the time run by yet another Deng Xiao-ping son-in-law.

CFIUS's Role in Magnequench
But the United States government surely would not permit the Chinese simply to walk in and take over a significant U.S. high-tech firm, would it? Several sources indicate that CFIUS did reach a "mitigating agreement"[14] with Magnequench's new owners that the Chinese companies could not remove Magnequench's production equipment or jobs from the U.S. for a period of ten years.[15]

It is, however, an old Chinese tradition that "rules are made to be broken" (shang you zhengce, xia you duice). Magnequench's Chinese owners cleverly reinterpreted the CFIUS conditions. One Magnequench employee reported that shortly after the Chinese took over, Magnequench's neodymium-iron-boron magnet production line was "duplicated in China" and that, after the Chinese "made sure that it worked, they shut down" the U.S. production in Indiana. The employee added, "I believe the Chinese entity wanted to shut the plant down from the beginning. They are rapidly pursuing this technology."[16]

Man, how does this refute any of my claims? It only backs up what I am saying - how much did those wheel motors weight? 150lbs each?

Here you go:
http://www.tm4.com/wp-content/uploads/2013/12/Wheel_motor_feature_Electric__Hybrid_July_2013.pdf
10 ft-lb per lb.
My point proven again. And that's a state of the art hub motor.

It was cancelled because it probably spun out as soon as it hit a bumpy road. Probably worse then an unloaded semi-truck.
You guys need to look at the big picture.
Show me a hub motor with 30++ ft-lb/lb, that's sealed, can last 100,000 miles, and doesn't cost $2000+ to manufacture.
Show me a hub motor system that can replace the friction brake.
Show me both and I'd embrace them.

Do you really consider 66lb (30kg) spread between four wheels is excessive? Even between two that's just fine by me. I'm pretty confident the driveshafts on my FWD car weigh 25-30kg combined.

I suspect there is a lot more unsprung mass on an average car than you realise!

Well, axles only partially contribute to sprung weight. Yeah, 66lb might be OK if everything else is optimized, and they can reduce brake size by using regen.
Id guess at ~50lbs per wheel sprung weight on a performance car.
The problem is I doubt you could get 2000ftlb from a 66lb motor, let alone 500ftlb from a 16.5lb motor, unless you are cooling the windings with liquid nitrogen! :-D

Because you don't know how to make the torque you are rightly not leading the motor development.

This fortunately has no impact on folks who do have the skills from developing them.

I've seen a pattern in your replies to my posts. You have yet to back up a single one of your arguments. (in fact, when you tried, it only showed facts which mirrored what I was saying, yet you continue to argue?) Come up with something substantive, for once? Do you really hate to be wrong that much? Is this an EE thing?

 

[okashira]

Ok, now I feel like this guy: :-(
http://4.bp.blogspot.com/-VcrNn8AiWMc/Tq2CavD4Y1I/AAAAAAAABCs/iv07lVmamsE/s1600/Someone+is+wrong+on+internet.png
I'll leave the thread alone...