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Discussion Starter #1
I have tested many motor designs and found that?its not all about rpm,s but torque that is the most important in any motor today.

?Having design my Gator Controllers and looking for more amps for more torque is not the answer.

What? is needs is to redesign the ac/dc motor, with a bigger armature having permanent magnets?in it.

This will have a diameter of say: 20inch with outer dc pulse field like advance step motor design.

This will do away with the speed controller and have a PWM without and IGBT or Mosfet.

The power output in torgue is unmatch by any dc/ac motor as smaller dc motor lose there torque at higher rpms?and have higher amps at start up, this new design would use less? amps and better torque output and it will reduce the rpms also.

Having reduce the weight about 50% compare to today motor would be the way to go.

I'm? not saying the best way, but its all about torque and not just rpms.

?

Tommey Reed

Rotarypistonengine.com

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Discussion Starter #2
Tommy, search YOUTUBE, for "Newman Motor" You'll find
many hobbyists making just such a motor you speak of
on a small scale.

I wish I had a shop, and tools to make a large one of
these motors to play with. My daughter plans on
making a small one for a science fair project, like
you'll find on youtube.

M.Barkley


--- [email protected] wrote:

>
> I have tested many motor designs and found that?its
> not all about rpm,s but torque that is the most
> important in any motor today.
>
> ?Having design my Gator Controllers and looking for
> more amps for more torque is not the answer.
>
> What? is needs is to redesign the ac/dc motor, with
> a bigger armature having permanent magnets?in it.
>
> This will have a diameter of say: 20inch with outer
> dc pulse field like advance step motor design.
>
> This will do away with the speed controller and have
> a PWM without and IGBT or Mosfet.
>
> The power output in torgue is unmatch by any dc/ac
> motor as smaller dc motor lose there torque at
> higher rpms?and have higher amps at start up, this
> new design would use less? amps and better torque
> output and it will reduce the rpms also.
>
> Having reduce the weight about 50% compare to today
> motor would be the way to go.
>
> I'm? not saying the best way, but its all about
> torque and not just rpms.
>
> ?
>
> Tommey Reed
>
> Rotarypistonengine.com
>
>
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> storage and industry-leading spam and email virus
> protection.
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>


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Discussion Starter #3
Actually, motors is an area where EVs don't really need much help. We
already have well-developed designs that get efficiency percentages in the
mid 90's. There is not a lot of room for dramatic developments in that
department. Serial production will take care of affordability.

Where we really need help is ... you guessed it ... it's the battery. I
really can't think of anything else holding EVs back.

David Roden
EVDL Administrator
http://www.evdl.org/


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Discussion Starter #4
Actually, motors is an area where EVs don't really need much help. We
already have well-developed designs that get efficiency percentages in the
mid 90's. There is not a lot of room for dramatic developments in that
department. Serial production will take care of affordability.

Where we really need help is ... you guessed it ... it's the battery. I
really can't think of anything else holding EVs back.

David Roden
EVDL Administrator
http://www.evdl.org/


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Discussion Starter #5
So you need to lok up the cisero motor design used in the solar chalenge races.

Google on: australia solar competition cisero motor design



Arak Leatham - Web and Desktop Systems Developer




Estimating, Point of Sale, Tracking, Reporting Applications> To: [email protected]; [email protected]> Date: Tue, 23 Oct 2007 14:58:50 -0400> From: [email protected]> Subject: [EVDL] New motor design will help the EV world!> > > I have tested many motor designs and found that?its not all about rpm,s but torque that is the most important in any motor today.> > ?Having design my Gator Controllers and looking for more amps for more torque is not the answer.> > What? is needs is to redesign the ac/dc motor, with a bigger armature having permanent magnets?in it.> > This will have a diameter of say: 20inch with outer dc pulse field like advance step motor design.> > This will do away with the speed controller and have a PWM without and IGBT or Mosfet.> > The power output in torgue is unmatch by any dc/ac motor as smaller dc motor lose there torque at higher rpms?and have higher amps at start up, this new design would use less? amps and better torque output and it will reduce t!
he rpms also.> > Having reduce the weight about 50% compare to today motor would be the way to go.> > I'm? not saying the best way, but its all about torque and not just rpms.> > ?> > Tommey Reed> > Rotarypistonengine.com> > ________________________________________________________________________> Check Out the new free AIM(R) Mail -- Unlimited storage and industry-leading spam and email virus protection.> _______________________________________________> For subscription options, see> http://lists.sjsu.edu/mailman/listinfo/ev
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Discussion Starter #6
I beg to differ. (If you please) Improvements ARE needed in Power to weight.
=

Power to weight is very important in high mileage vehicles and esp in the w=
heel hub area. Wheel hub motors eliminate about thier own weight in support=
ive drive hardware compared to inboard Edrives. Even more important conside=
ring sprung to unsprung weight in a light vehicle. =

=

Under normal conditions every pound of drive train is worth 2 to 3 lbs of a=
n ICE vehicle. And some similar added amounts in battery weight for EVs.
=

All totaled one pound of hub motor saved is about 5 to 10 lbs of additional=
E-vehicle gross weight (if everything is tightly engineered, which admitte=
dly, is usually not).
=

SO if that over-driven liquid cooled method could make a 1hp act like a 10h=
p hub motor, Then in a 3wheeler like mine, I can potentially save between 1=
50 and 300lbs of EV. That may reduce my 1000lb dry weight to 700lb.



Arak Leatham - Web and Desktop Systems Developer




Estimating, Point of Sale, Tracking, Reporting Applications> From: [email protected]=
rmm.net> To: [email protected]> Date: Tue, 23 Oct 2007 20:19:46 -0400> Subj=
ect: Re: [EVDL] New motor design will help the EV world!> > Actually, motor=
s is an area where EVs don't really need much help. We > already have well-=
developed designs that get efficiency percentages in the > mid 90's. There =
is not a lot of room for dramatic developments in that > department. Serial=
production will take care of affordability.> > Where we really need help i=
s ... you guessed it ... it's the battery. I > really can't think of anythi=
ng else holding EVs back.> > David Roden> EVDL Administrator> http://www.ev=
dl.org/> > > _______________________________________________> For subscript=
ion options, see> http://lists.sjsu.edu/mailman/listinfo/ev
_________________________________________________________________
Windows Live Hotmail and Microsoft Office Outlook =96 together at last. =
Get it now.
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Discussion Starter #10
Cool, let us know when you sucessuflly build this hub motor and then when
you get the retail price down below $10,000 a pop, I'm sure you'll have
lot's of customers.

>
> I beg to differ. (If you please) Improvements ARE needed in Power to
> weight.
>
> Power to weight is very important in high mileage vehicles and esp in the
> wheel hub area. Wheel hub motors eliminate about thier own weight in
> supportive drive hardware compared to inboard Edrives. Even more important
> considering sprung to unsprung weight in a light vehicle.
>
> Under normal conditions every pound of drive train is worth 2 to 3 lbs of
> an ICE vehicle. And some similar added amounts in battery weight for EVs.
>
> All totaled one pound of hub motor saved is about 5 to 10 lbs of
> additional E-vehicle gross weight (if everything is tightly engineered,
> which admittedly, is usually not).
>
> SO if that over-driven liquid cooled method could make a 1hp act like a
> 10hp hub motor, Then in a 3wheeler like mine, I can potentially save
> between 150 and 300lbs of EV. That may reduce my 1000lb dry weight to
> 700lb.
>
>
>
> Arak Leatham - Web and Desktop Systems Developer
>
>
>
>
> Estimating, Point of Sale, Tracking, Reporting Applications> From:
> [email protected]> To: [email protected]> Date: Tue, 23 Oct 2007 20:19:46
> -0400> Subject: Re: [EVDL] New motor design will help the EV world!> >
> Actually, motors is an area where EVs don't really need much help. We >
> already have well-developed designs that get efficiency percentages in the
> > mid 90's. There is not a lot of room for dramatic developments in that >
> department. Serial production will take care of affordability.> > Where we
> really need help is ... you guessed it ... it's the battery. I > really
> can't think of anything else holding EVs back.> > David Roden> EVDL
> Administrator> http://www.evdl.org/> > >
> _______________________________________________> For subscription options,
> see> http://lists.sjsu.edu/mailman/listinfo/ev
> _________________________________________________________________
> Windows Live Hotmail and Microsoft Office Outlook =96 together at last. =
Get
> it now.
> http://office.microsoft.com/en-us/outlook/HA102225181033.aspx?pid=3DCL100=
626971033
> _______________________________________________
> For subscription options, see
> http://lists.sjsu.edu/mailman/listinfo/ev
>


-- =

If you send email to me, or the EVDL, that has > 4 lines of legalistic
junk at the end; then you are specifically authorizing me to do whatever I
wish with the message. By posting the message you agree that your long
legalistic signature is void.

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Discussion Starter #12
Actually, Thrive.ch has offered thier 3kw scooter hubs for round $700 each =
delivered (if I order 40). And I can buy the same 3Kw rating here in the US=
for $650 and $850. These are powerful enough for my vehicle. These include=
controllers.
=

However, I would have to adapt them for side mounting. I have already appli=
ed that adaption to motorcycle rims on my Taddy.
=

Now All I need is $2500 and I can get started. Unfortuantely $$ is still my=
limiting factor.
- http://www.detalidon.com -(see last page)



Arak Leatham - Web and Desktop Systems Developer




Estimating, Point of Sale, Tracking, Reporting Applications> Date: Wed, 24 =
Oct 2007 00:34:18 -0700> From: [email protected]> To: [email protected]> Su=
bject: Re: [EVDL] New motor design will help the EV world!> > Cool, let us =
know when you sucessuflly build this hub motor and then when> you get the r=
etail price down below $10,000 a pop, I'm sure you'll have> lot's of custom=
ers.> > >> > I beg to differ. (If you please) Improvements ARE needed in Po=
wer to> > weight.> >> > Power to weight is very important in high mileage v=
ehicles and esp in the> > wheel hub area. Wheel hub motors eliminate about =
thier own weight in> > supportive drive hardware compared to inboard Edrive=
s. Even more important> > considering sprung to unsprung weight in a light =
vehicle.> >> > Under normal conditions every pound of drive train is worth =
2 to 3 lbs of> > an ICE vehicle. And some similar added amounts in battery =
weight for EVs.> >> > All totaled one pound of hub motor saved is about 5 t=
o 10 lbs of> > additional E-vehicle gross weight (if everything is tightly =
engineered,> > which admittedly, is usually not).> >> > SO if that over-dri=
ven liquid cooled method could make a 1hp act like a> > 10hp hub motor, The=
n in a 3wheeler like mine, I can potentially save> > between 150 and 300lbs=
of EV. That may reduce my 1000lb dry weight to> > 700lb.> >> >> >> > Arak =
Leatham - Web and Desktop Systems Developer> >> >> >> >> > Estimating, Poin=
t of Sale, Tracking, Reporting Applications> From:> > [email protected]> To: =
[email protected]> Date: Tue, 23 Oct 2007 20:19:46> > -0400> Subject: Re: [=
EVDL] New motor design will help the EV world!> >> > Actually, motors is an=
area where EVs don't really need much help. We >> > already have well-deve=
loped designs that get efficiency percentages in the> > > mid 90's. There i=
s not a lot of room for dramatic developments in that >> > department. Seri=
al production will take care of affordability.> > Where we> > really need h=
elp is ... you guessed it ... it's the battery. I > really> > can't think o=
f anything else holding EVs back.> > David Roden> EVDL> > Administrator> ht=
tp://www.evdl.org/> > >> > _______________________________________________>=
For subscription options,> > see> http://lists.sjsu.edu/mailman/listinfo/e=
v> > _________________________________________________________________> > W=
indows Live Hotmail and Microsoft Office Outlook =96 together at last. Get=
> > it now.> > http://office.microsoft.com/en-us/outlook/HA102225181033.asp=
x?pid=3DCL100626971033> > _______________________________________________> =
> For subscription options, see> > http://lists.sjsu.edu/mailman/listinfo/e=
v> >> > > -- > If you send email to me, or the EVDL, that has > 4 lines of =
legalistic> junk at the end; then you are specifically authorizing me to do=
whatever I> wish with the message. By posting the message you agree that y=
our long> legalistic signature is void.> > ________________________________=
_______________> For subscription options, see> http://lists.sjsu.edu/mailm=
an/listinfo/ev
_________________________________________________________________
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Discussion Starter #13
Ian Hooper wrote:
> I agree with David that energy storage is the biggest hinderance
> for EV adoption right now.

I disagree. Even if we had the ideal battery, there would be no mass
exodus. The auto industry would just invent new excuses.

Let's say we could buy a black-box battery with these specs:

- Cost: $1000 each.
- Weight: 500 lbs.
- Size: 18" x 18" x 18".
- Power: 100 KW peak (about 100 horsepower)
- Capacity: 50 KWH (for example, 240 volts at 200 amphours; enough for
a 200 mile range in a 250 WH/mile car)

EVer's might think this is absolutely great! But to the car industry,
this is only *half* the performance they are now getting from their
beloved ICEs: They have twice the horsepower, twice the range, half the
size and weight, and if we had the inside data, it probably costs them
less, too.

> I would also say that the series DC motors most of us use are
> rather caveman-tech.

You have a pretty high opinion of science in the stone age! :)

It is important to keep this all in perspective. Very few of the things
in our daily lives are actually "high tech". Most of the things around
you are just newer examples of things your grandparents had as well.
Look at your house, your car, the street where you live, etc. Their
appearance and styling may have changed, but their basic functionality
is the same.

Yes, the brushed DC motor is old technology. But so is your house, car,
TV, radio, telephone, furnace, refrigerator, etc. We've just "glitzed
them up" a bit. Too often, the newer versions cost more, have lots of
features you don't use, and break down and need replacement sooner.

> I would love to see big improvements in the affordability of AC
> drive systems in the next few years. Tesla have shown us what's
> possible, now to just get the price down by a factor of 10! ;)

Would you rather have a motor more like your computer, or your
refrigerator? Should it be very high tech, expensive, with lots of
features, but occasionally "crash" and need to be replaced every couple
years? Or should it be a completely bland commodity item, that just
plain works for decades without any maintenance at all?

>> I submit that the area of motor controllers is one that may need
>> improvement if EV's are to replace ICEV's.

I would apply the same sort of logic here. Do you want motor controllers
built like present automotive electronics? As cheap as possible,
completely undocumented and inscrutable inside, non-repairable and
hideously expensive to replace?

We are getting an example of what happens to EVs that take this design
approach. Those few of the auto company produced EVs that escaped the
crusher are turning out to be extremely difficult to repair. They
weren't designed to be serviced!

Personally, I'd like my EV to be more like a house than a car. A house
can last a very long time. It can be built and maintained by relatively
unskilled people, with simple tools. When things break or wear out, it's
easy get replacements.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #14
Arak Leatham wrote:
> Improvements ARE needed in Power to weight.

I would suggest that improvements are always wanted. Whether they are
"needed" is more complicated. If reduced size is free, of course people
want it! The problem is that you have to give up something to get it
(usually cost).

> Wheel hub motors eliminate about thier own weight in supportive drive
> hardware compared to inboard Edrives.

Going to a low-RPM high-torque hub motor usually takes you in the
opposite direction; they are *heavier* than an equivalent high-RPM
low-torque motor.

The nature of motor physics says the optimum design is a "square" motor,
with roughly the same length and diameter. This leads to a relatively
low pole count, and so a relatively high RPM. The best power-to-weight
ratio for a motor occurs at the highest RPM its strength of materials
allows. This requires a gear reduction, because the optimal tire size is
large, and so needs a low RPM.

Gearboxes tend to be smaller and lighter than motors for a given power
level. Built carefully, they can also be very efficient. It turns out
that a small high-speed motor and gear reducer is smaller, lighter,
cheaper, and more efficient than trying to do it with a direct-drive
motor. Therefore, most practical hubmotors are really gearmotors (a
high-speed motor with a gear reduction in the wheel).

Motors get more efficient as they get bigger. Total motor weight, size,
and cost will be less, too. This encourages us to have one big motor
rather than several little ones. This in turn means the motor is
centrally located; not in a wheel, so unsprung weight issues don't cause
problems.

There basically are no losses in a differential because you don't spend
any significant amount of time turning. This says a single larger motor
driving a differential is more efficient and perhaps even lighter than
two gearmotors driving the wheels separately.

All this means that the optimal configuration is a single motor, driving
a gear reduction, with some kind of drive train connecting it to the
wheels.

You can go "against the grain" if you like. The size, weight, and
efficiency consequences of a sub-optimal design can be overcome if you
spend enough time and money on perfection. A weak idea that is superbly
executed can beat out a better idea that is badly executed.
--
Ring the bells that still can ring
Forget the perfect offering
There is a crack in everything
That's how the light gets in -- Leonard Cohen
--
Lee A. Hart, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net

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Discussion Starter #15
Yes, that make sense. Thanks. Usually the the other weight factors are igno=
red, which is the point I wanted to make.
=

It would be possible to use a hydrolic distibution to all wheels from a cen=
tral CVT pump. Again there are many tradoffs. There was a recent Tadpole IC=
E built using that which was very interesting. I'ld like to see a Hybrid de=
sign for that one.
=

As for my DF design, vs the Taddy. I will stay with FWD over AWD for the re=
asons you noted. I need to find a suitable small Transaxle before I could c=
onsider a single motor in other than a hydrolic (Hydrostatic) drive. The VW=
bug tranny is just too big. And the CV2 Citrone is too big as well.
=




Arak Leatham - Web and Desktop Systems Developer




Estimating, Point of Sale, Tracking, Reporting Applications> Date: Wed, 24 =
Oct 2007 11:14:40 -0500> From: [email protected]> To: [email protected]=
u> Subject: Re: [EVDL] New motor design will help the EV world!> > Arak Lea=
tham wrote:> > Improvements ARE needed in Power to weight.> > I would sugge=
st that improvements are always wanted. Whether they are > "needed" is more=
complicated. If reduced size is free, of course people > want it! The prob=
lem is that you have to give up something to get it > (usually cost).> > > =
Wheel hub motors eliminate about thier own weight in supportive drive> > ha=
rdware compared to inboard Edrives.> > Going to a low-RPM high-torque hub m=
otor usually takes you in the > opposite direction; they are *heavier* than=
an equivalent high-RPM > low-torque motor.> > The nature of motor physics =
says the optimum design is a "square" motor, > with roughly the same length=
and diameter. This leads to a relatively > low pole count, and so a relati=
vely high RPM. The best power-to-weight > ratio for a motor occurs at the h=
ighest RPM its strength of materials > allows. This requires a gear reducti=
on, because the optimal tire size is > large, and so needs a low RPM.> > Ge=
arboxes tend to be smaller and lighter than motors for a given power > leve=
l. Built carefully, they can also be very efficient. It turns out > that a =
small high-speed motor and gear reducer is smaller, lighter, > cheaper, and=
more efficient than trying to do it with a direct-drive > motor. Therefore=
, most practical hubmotors are really gearmotors (a > high-speed motor with=
a gear reduction in the wheel).> > Motors get more efficient as they get b=
igger. Total motor weight, size, > and cost will be less, too. This encoura=
ges us to have one big motor > rather than several little ones. This in tur=
n means the motor is > centrally located; not in a wheel, so unsprung weigh=
t issues don't cause > problems.> > There basically are no losses in a diff=
erential because you don't spend > any significant amount of time turning. =
This says a single larger motor > driving a differential is more efficient =
and perhaps even lighter than > two gearmotors driving the wheels separatel=
y.> > All this means that the optimal configuration is a single motor, driv=
ing > a gear reduction, with some kind of drive train connecting it to the =
> wheels.> > You can go "against the grain" if you like. The size, weight, =
and > efficiency consequences of a sub-optimal design can be overcome if yo=
u > spend enough time and money on perfection. A weak idea that is superbly=
> executed can beat out a better idea that is badly executed.> -- > Ring t=
he bells that still can ring> Forget the perfect offering> There is a crack=
in everything> That's how the light gets in -- Leonard Cohen> --> Lee A. H=
art, 814 8th Ave N, Sartell MN 56377, leeahart_at_earthlink.net> > ________=
_______________________________________> For subscription options, see> htt=
p://lists.sjsu.edu/mailman/listinfo/ev
_________________________________________________________________
Windows Live Hotmail and Microsoft Office Outlook =96 together at last. =
Get it now.
http://office.microsoft.com/en-us/outlook/HA102225181033.aspx?pid=3DCL10062=
6971033
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Discussion Starter #16
I am a staunch FOSS advocate and believe that the same
philosophy should be applied to hardware when applicable, though I
concede that for some time to come it will apply in only very rare
circumstances. I certainly would not want an EV designed with a "black
box" approach.
However, my previous concerns as to motor controller design have
not been addressed. I reiterate that I am not educated enough to know
much about this subject, but from my reading the cost of components
and skilled labor is an irreducible factor, regardless of the openness
of the design. My belief is that the design should be entirely open,
since that will facilitate improvements as time goes on and the design
gathers eyeballs.
If you, Mr. Hart, know of ways around the problems I have dimly
perceived in the mass-production of motor controllers, I would be
eager to hear about them, although I may not have the background to
understand. In the meantime I continue to concede that the battery
problem is the main problem.
By the way: Thank you for all you do.
>
> Would you rather have a motor more like your computer, or your
> refrigerator? Should it be very high tech, expensive, with lots of
> features, but occasionally "crash" and need to be replaced every couple
> years? Or should it be a completely bland commodity item, that just
> plain works for decades without any maintenance at all?
>
> >> I submit that the area of motor controllers is one that may need
> >> improvement if EV's are to replace ICEV's.
>
> I would apply the same sort of logic here. Do you want motor controllers
> built like present automotive electronics? As cheap as possible,
> completely undocumented and inscrutable inside, non-repairable and
> hideously expensive to replace?
>
> We are getting an example of what happens to EVs that take this design
> approach. Those few of the auto company produced EVs that escaped the
> crusher are turning out to be extremely difficult to repair. They
> weren't designed to be serviced!
>
> Personally, I'd like my EV to be more like a house than a car. A house
> can last a very long time. It can be built and maintained by relatively
> unskilled people, with simple tools. When things break or wear out, it's
> easy get replacements.
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in -- Leonard Cohen

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Discussion Starter #17
the skilled labor part has been greatly exaggerated. the skill is
required in the design, not the assembly. just instruction
and the power electronics for a curtis has been estimated at 80$ in even
moderate volume

the battery tech is here too but to be practical we need a big company
to make large cheap packs available off the shelf so grease monkeys can
just plug it in. a bit like lead acids now.

Dan



Andrew Kane wrote:
> I am a staunch FOSS advocate and believe that the same
> philosophy should be applied to hardware when applicable, though I
> concede that for some time to come it will apply in only very rare
> circumstances. I certainly would not want an EV designed with a "black
> box" approach.
> However, my previous concerns as to motor controller design have
> not been addressed. I reiterate that I am not educated enough to know
> much about this subject, but from my reading the cost of components
> and skilled labor is an irreducible factor, regardless of the openness
> of the design. My belief is that the design should be entirely open,
> since that will facilitate improvements as time goes on and the design
> gathers eyeballs.
> If you, Mr. Hart, know of ways around the problems I have dimly
> perceived in the mass-production of motor controllers, I would be
> eager to hear about them, although I may not have the background to
> understand. In the meantime I continue to concede that the battery
> problem is the main problem.
> By the way: Thank you for all you do.
>

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Discussion Starter #20
I agree with what Lee is saying here, but I think you may be missing
his point (apologies if I did as well). In the "house built like a
car" analogy, there are certainly parts of a house that are easy to
service and repair, but not easy to construct yourself.

I recently replaced my water heater. I rerouted the plumbing, raised
it off the floor to meet code and raised the vent stack enough above
the roofline. I was able to "repair" my house with no special
knowledge, but a week worth of nights spent in the garage. Unlike a
modern car, I did not need to do any special programming with a black
box only available to Homebuilders so that my dishwasher would work
with this new waterheater.

On the flip side, there is NO way I would ever try to make a water
heater. Is it possible? Sure, a big metal tank with an old stove
burner under it. Is it efficient? Is it safe? Would I feel comfortable
sleeping in my house with that installed? No to all of them. I buy a
water heater so those things are taken care of for me by engineers who
know how to build products to meet safety and design constraints.

The same can be said of EV parts. Controllers and the like exist off
the shelf. These are easy to install and are not vendor locked. You
can use it how you see fit. That does not mean the design is free to
you, it means you can install it, use it and replace it yourself. Want
to build one? Go for it! The parts are available. No one is holding
you back. When you build it, it'll work in your EV. It's yours. Do you
trust it to not fail full on? Will it work after you hit that pothole
on the way home? Will it work when making a left across traffic? Do
your homework and it'll work great.

But these are the same reasons that I'm happy I can repair my house
and my EV, but will not build a motor controller (at least for on road
use) and I will not build a water heater for my house. These are
things I buy. The basics of any engineering project are simple;
getting it to work under all circumstances, or at least fail
gracefully, is what is difficult. When lives are on the line this is a
decision to weigh carefully.

I work in the electronics industry and I've seen many problems that
can happen with automated and manual labor manufacturing. If it can be
put together wrong, dropped, solder paste stencil gets clogged, you
name it, it'll happen sometime. Are there quality checks? Sure. They
cost money. So do quality engineers, component engineers and a whole
slew of people who support the manufacture of a quality product. Yes,
medical devices are mass produced, but I guarantee they don't charge
the same manufacturing costs as a microwave from Target.

Sorry if this email is snippy, but I get tired of the assertion that
since a product is produced, and the parts cost $X, then simply adding
the cost of the parts and two hours of labor makes a product. This is
simply not true.

Erik


Date: Wed, 24 Oct 2007 21:59:30 -0700
From: "Andrew Kane" <[email protected]>
Subject: Re: [EVDL] New motor design will help the EV world!
To: "Electric Vehicle Discussion List" <[email protected]>
Message-ID:
<[email protected]>
Content-Type: text/plain; charset=ISO-8859-1

I am a staunch FOSS advocate and believe that the same
philosophy should be applied to hardware when applicable, though I
concede that for some time to come it will apply in only very rare
circumstances. I certainly would not want an EV designed with a "black
box" approach.
However, my previous concerns as to motor controller design have
not been addressed. I reiterate that I am not educated enough to know
much about this subject, but from my reading the cost of components
and skilled labor is an irreducible factor, regardless of the openness
of the design. My belief is that the design should be entirely open,
since that will facilitate improvements as time goes on and the design
gathers eyeballs.
If you, Mr. Hart, know of ways around the problems I have dimly
perceived in the mass-production of motor controllers, I would be
eager to hear about them, although I may not have the background to
understand. In the meantime I continue to concede that the battery
problem is the main problem.
By the way: Thank you for all you do.
>
> Would you rather have a motor more like your computer, or your
> refrigerator? Should it be very high tech, expensive, with lots of
> features, but occasionally "crash" and need to be replaced every couple
> years? Or should it be a completely bland commodity item, that just
> plain works for decades without any maintenance at all?
>
> >> I submit that the area of motor controllers is one that may need
> >> improvement if EV's are to replace ICEV's.
>
> I would apply the same sort of logic here. Do you want motor controllers
> built like present automotive electronics? As cheap as possible,
> completely undocumented and inscrutable inside, non-repairable and
> hideously expensive to replace?
>
> We are getting an example of what happens to EVs that take this design
> approach. Those few of the auto company produced EVs that escaped the
> crusher are turning out to be extremely difficult to repair. They
> weren't designed to be serviced!
>
> Personally, I'd like my EV to be more like a house than a car. A house
> can last a very long time. It can be built and maintained by relatively
> unskilled people, with simple tools. When things break or wear out, it's
> easy get replacements.
> --
> Ring the bells that still can ring
> Forget the perfect offering
> There is a crack in everything
> That's how the light gets in -- Leonard Cohen

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