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Dutch Invention Uses Electric Engines For Wheels
Makarand writes "A Dutch invention is
promising to make vehicles atleast 50% more efficient
and also bring down the soot and carbon dioxide emissions. This is made possible by replacing
the conventional wheels by 'in-wheel' electric engines which are normal electric engines turned inside
out. No transmission is necessary as the in-wheel engines are powered by battery-packs installed on
the vehicle. A diesel-powered generator which replaces the original engine on the vehicle
charges the battery-pack continuously. The Dutch company
E-Traction has built a bus using this technology that
will undergo testing for the next six months."
Back in the ol' Apollo days, NASA's lunar rover operated in exactly the same fashion, if I recall correctly.
l o/ lrv/lrv.htm
http://www.nasm.si.edu/collections/imagery/apol
Just because you can mod me down, doesn't mean you're right. Shoes for industry!
Interesting idea, but the real test will be with long term cost of operation. The cost of diesel fuel may be insignificant if this thing spends significantly more time in the garage, or costs more to build.
Not that I want to be a naysayer. I hope it pans out, but don't be too surprised if it quietly goes away never to be heard from again lot a lot of other great ideas. (I remember a british high speed train that leaned into curves, that was quietly taken out of service after much initial fanfare)
My rights don't need management.
Won't the gyroscpic effect of that heavy a wheel be a lot to overcome. Also, magnetic brakes, I'd hate to be going down a hill with low batteries, and have the engine stall.
...can be bad because of its lack of noise, there's less warnings to the pedestrians that the bus is coming. It may seem like a silly problem, but the next time you walk on the streets, check to see how often you use the sound as a cue to determine when a car is coming. Of course, you'd still look to be sure, but for jaywalkers, it could be a bad thing.
The other thing is, since the motor is now the wheel, I wonder what the costs will be to maintain these wheels. I think it's still better to have traditional electric motors with the rotor on the inside, since there's really not that much to gain from having an inside out motor, and more to lose when you need to get at it to fix it. Using traditional motors rather than the inside-out motor also means less change need to be made, since the wheels and tires can be used from currently available parts.
They put the engine in the wheel, massively increasing the amount of unsprung weight. The benefits from this layout can't possibly outweigh the huge drawbacks.
This idea will never be marketable, as the vehicle will handle terribly and have a terrible ride.
While having the motor built into the hub reduces the number of parts and connectors (shafts, u-joints) that rob efficiency, it would seem the major item for efficiency is not so much because of the "inside out" motor, but because of the direct drive on the wheel with fewer parts.
This same company has a similar motor for smaller vehicles here. It uses short axles so the motor is not direct on the wheel.
There are some space considerations with this motor, but while it would work on a bus, such a large amount of unsprung weight on a smaller vehicle would not promote a great ride or handling.
Among one of my personal projects was an electric car, which I tried to make out toothpaste boxes/etc. The most natural way to move the car was, ofcourse to attach the electric motor (I had only one) to one of the wheels. I did this by attaching a small wheel to the motor shaft. Ofcourse, it didn't work out right: because of only one moving wheel, the car moved in circles, rather than straight as desired.
My point is: doesn't attaching the engine to the wheel seem like the *most* logical choice in the first place? Why build complicated transmission mechanisms and a centralized engine in the first place? The reason, I think was to use only one big powerful engine to power all wheels (or two, incase of a 2 wheel drive) simultaneously. Since the engine is the single most expensive component of a vehicle, it made sense to use only one of them, especially so, because most of them have a very high space:power ratio.
Electric motors seem to suffer from the same problem (high traction motors are incredibly huge). I would like to see figures on the size/power of these engines, and ofcourse, the size/weight of the batteries which the vehicle would need to haul along.
An Indian-American Hindu committed to non-violent thought/speech/action alarmed by the global explosion of radical Islam
I, for one, will welcome the results of the real-world tests of this thing. If it works as well as they claim, they could put those wheel-gines in all sorts of vehicles. And based on the size of them, I'd say they're going in large vehicles first. Can you imagine the Hummer ad campaign when the release a vehicle that is more fuel efficient than a Toyota Echo?
The CB App. What's your 20?
All I can say is flat flat flat, not the tire the Netherlands ;-). Unsprung weight is not to important in a low performance vehicle running on good roads (Apeldoorn has well maintained roads, you should see the taxes here). In a bus the unsprung mass will still be rather a small proportion of the total mass even for rather massive wheel motors. The big bastard springs that carry all that bus will not have to much trouble holding the wheels on the road.
Nadolig llawen,
R.
Maybe you live in interesting times
Although we're still a long ways away from mandatory mass transit or fully automated "cars" (a la Minority Report), I still fear that in my lifetime gasoline burning vehicles may be severely restricted in some parts of the world.
This doesn't bother me in principle, except that no one has made a feasible hybrid/alternative motorcycle. Reasonable bikes these days get 50-60 miles per gallon, so it hasn't been a concern, but with "vehicles" like the Honda Insight getting 70+ mpg in the city, bikes may soon need to worry about having a reputation as gas guzzlers.
Anyway, here's to hoping Janklow gets the maximum sentence.
I remember some years ago reading an article about the potential hazard to careless pedestrians of virtually silent electric vehicles, the obvious solution being to put a loudspeaker on them and play a suitable sound. One suggestion was the sound of horses' hooves.
Using HTML in email is like putting sound effects on your phone calls. Just say <strong>no</strong>.
What happens when the bus gets a flat? That does happen every now and again. It seems like the weight of the bus will fall on the engine. Are they planning on putting 2 tires in each wheel well (like a truck) in case this happens. Also, will you need to keep a spare engine in the trunk in case you do get a flat and you need to change the tire.
I guess this might not be a big deal for a city bus company, since they can just radio HQ and get someone to drive out with a new engine. But if this technology were ever used in real cars, that would be a major drawback.
Making a wheel that is an electric motor would make such a heavy wheel thtat the vehicle would handle and drive like total crap. The huge weight of the wheels would require shock absorbers with huge dampening ability to keep the wheel planted on the road over uneven surfaces. It would ride like a dump-truck.
In addition, you wouldn't be able to buy aftermarket wheels (no rims that spin at the traffic light), so no buying a set for winter. The obvious solution is to move the motor inboard and connect it with a short axle.
"We returned the General to El Salvador, or maybe Guatemala, it's difficult to tell from 10,000 feet"
They are selling the motor-wheel, you can find more information about it on the web site of a Hydro-Quebec subsidary M4.
The project of building a complete car from scratch was abandonned because it needs massive investments. They figured it would be easier to find partners and license this technology. GM bought a license.
Another reason why they prefer licensing the technology is that is may be not a great idea to put all this weight in the wheel. Taking a bump could easily destroy the suspension.
Virtually identical designs were used almost a century ago.
OTOH, this is why inventions eventually enter the public domain...
Ferdinand Porsches first patent IIRC was an electric car with motors-in-wheels, regenerative braking. all wheel drive, etc.
Had lead acid batteries, which made it impractical, which is still the case for the most part.
A hybrid is , has been, and will be, the only sensible solution for a LONG time.
Absolutely nothing new here.
Hydro-Quebec developped an electric motor-wheel about 5 years ago. Why would a gov. hydroelectrical agency build that? It's the question they answered when pulled the plug on the project, unfortunately :(
However, I am a little concerned about the longevity of the moter, as it would be subjected to every pothole and bump.
The grass is only greener, if you don't take care of your own lawn.
Yes, this is a problem. The solution might be a shaft, but then you have two universals to deal with. How about something even more radical: fix the wheel and put the springs into the tire. Wheel diameter has always been limited by the shaft necessary to drive it. If the wheel drives itself, you don't need the shaft. Why not make the wheel larger in diameter, and build springs and shock absorbers into the tire? For that matter, why not make the shock absorbers be electromagnets which dump current into the batteries?
-russ
Don't piss off The Angry Economist