# What is the name of the 4-motor electric vehicle prototype?



## Jan (Oct 5, 2009)

Maybe you mean:

http://www.proteanelectric.com/


----------



## Ziggythewiz (May 16, 2010)

That's a pretty sweet illustrative video...though the example car could have been better chosen...


----------



## pyramidhead (Mar 16, 2011)

mitsubishi made one like that on the prior lancer-evolution chassis as well:

http://www.worldcarfans.com/10508248659/mitsubishi-lancer-evolution-miev

(apologies for resurrecting a thread from last month, i'm researching and thought this was worth sharing.)


----------



## algea07 (Oct 1, 2010)

pyramidhead said:


> mitsubishi made one like that on the prior lancer-evolution chassis as well:
> 
> http://www.worldcarfans.com/10508248659/mitsubishi-lancer-evolution-miev
> 
> (apologies for resurrecting a thread from last month, i'm researching and thought this was worth sharing.)


why do they keep making cool cars then refusing to sell them to me?


----------



## oddysea (Mar 22, 2011)

Jan said:


> Maybe you mean:
> 
> http://www.proteanelectric.com/


The reason is that they don't actually work. 

Can anyone show me video of a hub motor vehicle that actually does what the manufacturer says it does? 
THe protean company back in 2007 or 8 said they could make a 400+ horsepower mini with hub motors. But noone ever actually saw it in operation. And the company that made the motors (PML?) became... Protean - and I still see no video footage of their 'system' operating.


----------



## fx4lightning (Mar 19, 2011)

Hi
my first post  Maybe not what you were looking for but


the Hydro Quebec hub motor has been around for a while. Since 1994 actually, so long it's hard to find it on the web.
I'm trying to find a vid that I saw back then with a converted 1994 Dodge Intrepid 
making smoke shows with the 4 wheels and making 0-60 in 5 or 6 sec but it seem to have disappeared



here is two articles of it sorry it's French Canadian first one has a vid in it from 1995 you can see the intrepid in it 
and the generator that was in the trunk of the car running on a test bench
http://blogue.transportsquebec.com/2010/05/20/tm4-fait-du-surplace-avec-le-moteur-roue/
http://www.radio-canada.ca/actualite/decouverte/flash/moteur-roue.html
And here is the web site of the company that develop the idea
http://www.tm4.com/electric_corner_module.aspx
and hey what do you know a Wiki article on it
http://en.wikipedia.org/wiki/TM4_Electrodynamic_Systems
And a video of a Michelin working prototype 20 years late
http://www.youtube.com/watch?v=i1uTR-8KarE&feature=player_embedded


----------



## oddysea (Mar 22, 2011)

fx4lightning said:


> Hi
> my first post  Maybe not what you were looking for but
> 
> 
> ...



Thanks for the info and congrats on your first post.

Your links emphasise my point - it seems that this is another in a long line of 'hub motor' vehicles that have never eventuated. 
The michelin wheel has been around for a while now - I think since 2008 (announced) and it has yet to be used in a real vehicle.

Has ANYONE solved the problems of multiple hub motors?


----------



## aeroscott (Jan 5, 2008)

check out the Eliica or something built in Japan very fast 8 wheel motors , 8 wheels .


----------



## yosemitesamiam (Feb 7, 2012)

oddysea said:


> The reason is that they don't actually work.
> 
> Can anyone show me video of a hub motor vehicle that actually does what the manufacturer says it does?
> THe protean company back in 2007 or 8 said they could make a 400+ horsepower mini with hub motors. But noone ever actually saw it in operation. And the company that made the motors (PML?) became... Protean - and I still see no video footage of their 'system' operating.


sorry if bringing back a year old thread is bad news...but I'd have to agree...they never want to sell it because they can't? Is it just not possible to get the motors working together with one controller? 

I know in golf cart terms, a 4x4 cart with two motors was never ironed out fully...and that seems way simpler! 

hmmmmm, and OH to make this work! Anyone else determined to see it work? I would like to!


----------



## Ziggythewiz (May 16, 2010)

I don't think the issue is making the motors work off one (or more) controllers. The issue is unsprung weight. Driving on a typical road is like taking a baseball bat to your expensive electronics, while spinning them on a centrifuge, good idea? So just solve the gravity issue and hub motors will work great.


----------



## lutach (May 31, 2011)

Eliica. Not 100% sure, but I think the Eliica is the only fully functional concept car so far that uses motos at each wheel. It's the only one that has reached 230mph in 2004.


----------



## yosemitesamiam (Feb 7, 2012)

Ziggythewiz said:


> I don't think the issue is making the motors work off one (or more) controllers. The issue is unsprung weight. Driving on a typical road is like taking a baseball bat to your expensive electronics, while spinning them on a centrifuge, good idea? So just solve the gravity issue and hub motors will work great.


No...nor will it ever be. Spinning creates gravity, it doesn't reduce it. 

On that note...now talking in terms of ground clearance here...so trucks, SUVs...etc...what if you took a playing card from the H1 hummer...inboard brakes, etc. Use an electric motor at each wheel station, run it through a short shaft...have the brakes and all tucked up there instead of in the wheel...I know this has all been discussed, reviewed, etc...I'm just not sure why it is taking this long for anyone to actually do it. Where is the hold up? I'm sure a guy like Major will chime in (lol)...cost, efficiency, power of each motor...? Or something else entirely, like a suitable donor with sufficient ground clearance? Seems a small car would not be a good suitor without modifications to the floor pan. And even in a big SUV, you could always go with some geared portal axles! Can someone say "electric Unimog?"

OK, getting ahead of myself.

Sam


----------



## yosemitesamiam (Feb 7, 2012)

OK, this is what I'm talking about! 

http://www.youtube.com/watch?v=bBR2NUVa-Z8

of course, not a bus...but this concept...moving a heavier rig around like an exped/suburban, etc like this, and possibly with a small diesel as a generator to offset costs of batteries... maybe a 1.9 VW TDI engine?


----------



## Daanii (Sep 3, 2009)

We are building a car with one motor per wheel. Each motor is mounted to the chassis (and so is sprung weight). Each motor connects to the wheel via a half shaft with a continuous velocity joint on each end. 

So far we only have motors on the rear wheels. But there are lots of advantages to the approach. For one thing, you can implement the differential by software. 

Why don't the carmakers try something new? Too risky. Just think back to when there were the first "horseless carriages." People took out the horse and put in an engine or motor. They went with what they knew. It took many years for cars to begin to look like cars, not carriages. 

Electric cars today look just like gasoline cars. People just take out the gasoline engine and put in an electric motor. It may take many years for electric cars to look, and work, dramatically differently from gasoline cars. 

But I think they will.


----------



## yosemitesamiam (Feb 7, 2012)

I applaud this post. So very true. 

My understanding is that with a motor driving each wheel you no longer need a typical differential or a transmission. The gear reduction can take place at the wheel...is this true in your findings?

Also depending on application, what is a typical sized motor at each wheel? I would think a 80kw size would do just fine especially in a heavier rig.


----------



## DrOof (Feb 11, 2012)

I really like the idea. It would make the car more simple in many ways. Are there any hub-motor systems for sale already?


----------



## charliehorse55 (Sep 23, 2011)

Perhaps you are thinking of the Concept_One by Rimac motors?

http://www.rimac-automobili.com/concept_one/introduction-20

http://www.youtube.com/watch?v=8BV1FCMGgps


----------



## Duncan (Dec 8, 2008)

Hi Guys

This is the only successful application of this concept

http://www.hq.nasa.gov/alsj/lrvhand.html

But it was amazingly successful!

As a very general rule
Torque is proportional to weight
The amount of torque required at the wheel would require a very heavy motor
This is "fixed" by gearing the motor
So I have got to have gears
So for two wheels I can have two motors and two gearboxes or
One motor and a diff (the diff does the gearing)
Why not use a diff? - its cheap, reliable, efficient


----------



## yosemitesamiam (Feb 7, 2012)

If you use a portal type axle you can accomplish gearing in the hub of the wheel and gain more ground clearance as well thus lowering the vehicle, reducing drag, etc I would think.


----------



## wubbert (Apr 20, 2010)

Don't forgot :

http://www.e-traction.nl

http://http://www.e-traction.nl/projects/mercedes-g-test-vehicle


----------



## DrOof (Feb 11, 2012)

Hm. Their 470 mm wheels looks suitable for a sedan size car. But at 70kg of unsprung weight...? Could that be an issue?
Also, any indication of costs?


----------



## iti_uk (Oct 24, 2011)

yosemitesamiam said:


> Spinning creates gravity, it doesn't reduce it.


Spinning creates gravity? Please cite something which supports this, I've never heard that before. If you mean to be talking about centripetal forces, then yes.

Also, what do you envision your 80kW per wheel vehicle capable of doing? That's 320kW total - that's 430hp! And probably more torque than you could use.

Daanii, I'm also planning a similar vehicle to the one you describe. Mine won't be a hypercar, so I'm looking at using four 12kW motors with a 5:1 reduction gearset for each - plenty for a sub-1 tonne commuter, I'd expect...

Chris


----------



## wubbert (Apr 20, 2010)

DrOof said:


> Hm. Their 470 mm wheels looks suitable for a sedan size car. But at 70kg of unsprung weight...? Could that be an issue?
> Also, any indication of costs?


They teach u that school, but attach plates of 70KG on youre rear wheel
It feels fine!!

The wheels under the Mercedes G are even 150KG (old prototype wheels) 
And it handles great!

The wheels are still prototypes,so now the are too expensive..but give it time!
The 470's wil be pefect under a sedan/saloon/station!


----------



## wubbert (Apr 20, 2010)

iti_uk said:


> so I'm looking at using four 12kW motors with a 5:1 reduction gearset for each - plenty for a sub-1 tonne commuter, I'd expect...
> 
> Chris


Please look for direct dive, reduction is noisy and kills youre efficiency

i'm planing a reverse trike with these wheels:
electric_car_hub_motor_7kw


----------



## iti_uk (Oct 24, 2011)

wubbert said:


> Please look for direct dive, reduction is noisy and kills youre efficiency


I'd be using a planetary gearset, the efficiency of which would be up in the 90% range. I'd rather take the slight hit on mechanical efficiency for a torque multiplier than increase the current and copper mass of the motor for acceptable low-speed acceleration.



wubbert said:


> i'm planing a reverse trike with these wheels:
> electric_car_hub_motor_7kw


Interesting motor, but I want to avoid in-wheel motors.




wubbert said:


> They teach u that school, but attach plates of 70KG on youre rear wheel
> It feels fine!!
> 
> The wheels under the Mercedes G are even 150KG (old prototype wheels)
> And it handles great!


Unsprung mass effects the ride quality, NVH and performance of your vehicle.

A heavier wheel will require a stiffer spring to maintain contact with the road on un-billiard-table-like surfaces, and a stiffer spring will require harder damping to avoid under-damped, "bouncy" suspension. The combination of both will increase the harshness of the ride and will increase stresses on the various suspension mounting points on the vehicle, possibly requiring reinforcement and therefore further vehicle mass increases.

A heavier wheel will also act as a flywheel (multiply by however many wheels you have on your vehicle). 70kg of added rotational mass on each wheel would certainly kill acceleration and will have a negative effect on braking performance.

To say that adding 70kg to each wheel resulted in a vehicle which felt "fine" means that either you were driving on a billiard-table-smooth surface without fast acceleration or deceleration, or you were barely moving at all. Or your judgement of "fine" needs recalibration...  I can feel a difference on my current car, between "normal" wheels and "lightweight" wheels, and the difference there is only a few kg per wheel, let alone 70kg!

Not to mention that 70kg on each rear wheel or driven wheel (in my case it would be four wheels) represents a huge chunk of the total vehicle mass. 280kg just for the wheels? I'd expect the entire rolling chassis to weigh less than that!

This is not to say that a car with 70kg wheels would not literally _work_, but in the same way, using lead-acid cells will _work_, it's just far from ideal.

This is not just "school textbook" stuff, this is measurable and can be felt in practice too. There is a reason why OEMs spend so much money trying to reduce the unsprung mass on the vehicles they produce.

The only way the 150kg wheels on a Mercedes G would feel "fine" and would handle "great" would be in the same way that running 100m while carrying your partner on your back is "possible" or the way that the food in the canteen at work is "edible".  All of these things under normal circumstances are best avoided.

Chris


----------



## MalcolmB (Jun 10, 2008)

That's a good summary Chris. Have you already found a source for your planetary gearsets or do you intend to build your own?


----------



## iti_uk (Oct 24, 2011)

MalcolmB said:


> That's a good summary Chris. Have you already found a source for your planetary gearsets or do you intend to build your own?


I'm currently considering Perm-Motor's PMS 120 (water cooled), and their site suggests that gearing is available. I need to contact them to find out the nature of that gearing - if it's not suitable I'll get hunting for off-the-shelf solutions, although having a set of gears manufactured is not impossible, although I'd like to do some level of durability simulation before hand and I don't have direct access to the solvers at work. 

Chris


----------



## palmer_md (Jul 22, 2011)

First time I saw this thread title, I thought of this vehicle. Then I saw the date and realized the Rimac ConceptOne had not been released yet. I still think this drive-train packaging is absolutely fantastic. Love the 4 motors and gearbox setup as well as the 20aH cell packaging. 










http://www.rimac-automobili.com/concept_one/introduction-20


----------



## MalcolmB (Jun 10, 2008)

Sounds good. It's been a while since I looked at the Perm motors. 800 Nm at the wheels and sub-1000 kg should be quite nippy. Since you're going for four-wheel drive I'm guessing you have some ideas for playing with traction control?


----------



## iti_uk (Oct 24, 2011)

MalcolmB said:


> Sounds good. It's been a while since I looked at the Perm motors. 800 Nm at the wheels and sub-1000 kg should be quite nippy. Since you're going for four-wheel drive I'm guessing you have some ideas for playing with traction control?




The traction-control is the main focus of my project. Haven't decided how to implement it yet, my current thinking is that each motor will have it's own controller (as supplied as standard with the PMS 120). The "throttle" (control input) for each will be governed by a central ECU which will primarily monitor individual wheel speeds, steering angle and "throttle" pedal inputs and possibly body-mounted accelerometers to adjust the four individual motor controllers accordingly.

The only custom electronics here would be the central ECU, so keeping a maximum of off-the-shelf components. It's still very much in the "logic" stage of conceptualisation, a LONG way to go yet.

Chris


----------



## iti_uk (Oct 24, 2011)

palmer_md said:


> Rimac ConceptOne


Interesting concept and I like the drivetrain layout. Not such a fan of having the cells inside the crash structure at the front and rear though...

Chris


----------



## epyon (Mar 20, 2008)

Tesla X bet them to the punch !!


----------



## bjfreeman (Dec 7, 2011)

iti_uk said:


> The traction-control is the main focus of my project. Haven't decided how to implement it yet, my current thinking is that each motor will have it's own controller (as supplied as standard with the PMS 120). The "throttle" (control input) for each will be governed by a central ECU which will primarily monitor individual wheel speeds, steering angle and "throttle" pedal inputs and possibly body-mounted accelerometers to adjust the four individual motor controllers accordingly.
> 
> The only custom electronics here would be the central ECU, so keeping a maximum of off-the-shelf components. It's still very much in the "logic" stage of conceptualisation, a LONG way to go yet.
> 
> Chris


the controller uses the Canbus for control. Follow the anti-skid instrumentation model that is feed back to to the ECU.

You can start with an http://www.sparkfun.com/products/10039
to build your antiskid uni for each wheel.


----------



## bjfreeman (Dec 7, 2011)

epyon said:


> Tesla X bet them to the punch !!


looks like more a two motor four wheel drive closer to gas drive train.
http://www.teslamotors.com/modelx


----------



## iti_uk (Oct 24, 2011)

bjfreeman said:


> the controller uses the Canbus for control. Follow the anti-skid instrumentation model that is feed back to to the ECU.
> 
> You can start with an http://www.sparkfun.com/products/10039
> to build your antiskid uni for each wheel.


Ah interesting, thanks.

Chris


----------



## DJBecker (Nov 3, 2010)

iti_uk said:


> Ah interesting, thanks.
> 
> Chris


I wouldn't even start to consider that for a major project like traction control and wheel synchronisation.

A basic CAN bus controller doesn't make suddenly make a AVR more capable. You need considerably more compute power for many tasks than an 8 bit processor can provide. You can get a ARM Cortex-M4 processor with floating point and a much better CAN controller for the same price.


----------



## GizmoEV (Nov 28, 2009)

bjfreeman said:


> looks like more a two motor four wheel drive closer to gas drive train.
> http://www.teslamotors.com/modelx


Except no motor under the hood. That is why they have such a big crumple zone.


----------



## iti_uk (Oct 24, 2011)

DJBecker said:


> I wouldn't even start to consider that for a major project like traction control and wheel synchronisation.
> 
> A basic CAN bus controller doesn't make suddenly make a AVR more capable. You need considerably more compute power for many tasks than an 8 bit processor can provide. You can get a ARM Cortex-M4 processor with floating point and a much better CAN controller for the same price.


To be honest, I'm thinking more of a PIC processor-based circuit, but like I've mentioned, this is REALLY early days so far.

Chris


----------

