[ausev] Wheel motors, was Re: Toyota Landcruiser conversion

[Ian Ward]

I spoke to a Lotus engineer at NADA that has been involved in the design
concept they are working on for ZAP, and he said that the difference in
unsprung weight between the ice version of the car with performance disc
breaks and the hub motors made by PML Flightlink (also used on the Mini
conversion they did) is only about 14 lbs.  Granted, any increase in
unsprung weight can impact handling, but this easily falls within the weight
difference between a performance wheel and stock wheel.  I'm still skeptical
of this claim, but until I do the research and add up the numbers, I can't
be too critical.  There is certainly a lot of weight in big performance
discs, calipers, bolts, lugs and bearings, so maybe it isn't such an
outrageous claim.

You are still correct, though - this is not a project for a hobbyist.  The
complexity of the controller(s) for all wheel drive that takes turning,
slippage and traction control into consideration is more than I would feel
confident taking on.

On 2/14/07, Christopher Robison <eeyore at phototropia.org> wrote:
>
> I think wheel motors are an interesting idea, but they present some
> problems for someone building an EV.
>
> First is availability. They're not really an off-the-shelf component
> that we can easily just go out and buy from companies like EV Parts and
> KTA, like normal EV motors.
>
> More importantly however, is the handling problems they cause. By having
> that much mass in your wheels, it becomes very difficult to keep the
> wheels planted on a bumpy road surface at high speeds. A wheel that's up
> in the air after a bump at any particular moment is a wheel that can't
> help with traction, cornering or braking. Google for the phrase
> "unsprung weight" and you'll find a lot of discussion about this issue.
>
> There are some current efforts to develop practical vehicles based on
> wheel motors and ultimately I think it could be a very good idea, but I
> don't believe it's a practical alternative for people doing their own
> garage conversions today.
>
>   --chris
>
>
>
> On Wed, 2007-02-14 at 09:49 -0800, Clendon Gibson wrote:
> > Perhaps this would be a good vehicle to use wheel mounted electric
> motors in? Would that not do away with the 4WD transmission issue?
> >
> > ----- Original Message ----
> > From: Christopher Robison <eeyore at phototropia.org>
> > To: AustinEV News Announcements and General Discussion <
> ausev at austinev.org>
> > Sent: Wednesday, February 14, 2007 11:29:13 AM
> > Subject: Re: [ausev] Toyota Landcruiser conversion
> >
> > This could be a really fun project. I think the older jeep-style FJ40
> > Land Cruisers were a lot cooler than the current behemoth luxury SUVs
> > under the same name. A bit of attitude they're trying to bring back with
> > the FJ Cruiser. You probably won't find any OEM parts for it, but the
> > old style Land Cruisers have enough of a fan base that there are
> > companies making replacement parts. This typically means they'll be
> > available, but expensive.
> >
> > The reality is that your two questions answer each other. Whether or not
> > your conversion will be able to keep up with traffic depends greatly on
> > how much money you have to spend on it. Plan your budget starting at
> > about $10k for the conversion, but more if you want to maintain any of
> > the FJ's capabilities in off-roading etc.
> >
> > A couple things learned for certain in Nick's Cherokee conversion.
> > First, having a boxy vehicle with a lot of frontal area makes it more
> > difficult to have decent range.  Second, keeping the 4wd parts (transfer
> > case, front driveshaft and axle) makes it even worse.
> >
> > How far is your commute?  Would you be able to plug in at work?  If
> > you're doing mostly 40-50mph, your range will be noticeably better than
> > having to drive 60-65.
> >
> > Bottom line: this conversion won't be cheap to do, as you have many
> > factors working against you: Weight, aerodynamics, obscure and expensive
> > parts, inefficient 4WD drivetrain.  However, it would be a really cool
> > vehicle when complete, if enough money is spent to do it right.
> >
> >   --chris
> >
> >
> >
> > On Tue, 2007-02-13 at 16:13 -0600, charles winningham wrote:
> > > Hello all,
> > >
> > > I am an aspiring electric car owner who has come into the opportunity
> > > to purchase a 1983 Toyota Landcruiser for next to nothing.  I would
> > > like to buy it and convert it to electric for the purpose of being a
> > > commuter car but I have some concerns and I do not know exactly how
> > > much it would cost to do a competent conversion of this particular
> > > model.
> > >
> > > My main concerns are 1) will it be able to keep up with the speed of
> > > traffic on my commute? (does not include freeway driving but does
> > > include a short stretch of driving on the access road to MOPAC) 2) how
> > > much will it cost? (any range, however appoximate, would help)
> > >
> > > Thank you all for making this community happen.  It's awesome to have
> > > something that actually enables me to do something about how much I
> > > hate driving a petroleum-fed car.
> > >
> > > Charles Winningham
> > > _______________________________________________
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> > > AusEV at austinev.org
> > > http://www.austinev.org/mailman/listinfo/ausev
> >
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> >
> >
> >
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