Subaru Hybrid

[H]

Fuji Heavy Industries, the maker of Subaru vehicles, will postpone its
release of a hybrid car in 2006 due to cost issues in its current design.

Fuji Heavy had been developing a hybrid car using its own powertrain,
although the possibility of a Toyota-Fuji Heavy hybrid alliance emerged
earlier this year. (Earlier post.)

The earlier report suggested that under the potential partnership, Toyota
would supply its hybrid drive system to Fuji Heavy in return for Fuji Heavy
supplying Toyota with advanced lithium-ion batteries for use in hybrids.

Fuji Heavy makes only some 590,000 vehicles a year-too low a volume for it
to cost-effectively develop its own hybrid technology, which is the path the
company has been taking.

According to the latest report, Fuji Heavy has not managed to reduce the
production cost of its own hybrid system to the point of being commercially
viable, and so is giving up on rolling out the hybrid on the original
schedule.

The automaker is now reportedly turning to Toyota's hybrid technology, with
a revised plan of debuting the Subaru hybrid in 2008.

GM is Fuji Heavy's top shareholder, but the GM-DaimlerChrysler dual-mode
hybrid technology under development apparently does not fit the application
(or the timing) Fuji Heavy has in mind.


Then the
http://media.mitsubishi-motors.com/pressrelease/e/corporate/detail1269.html
may be of greater interest to you.
- - - - - -
Mitsubishi Motors has already started development and testing of the MIEV
concept using a production compact vehicle, Colt, to serve as the rolling
test bed. The Colt EV uses rear in-wheel motors powered by a lithium-ion
battery system. The company is also currently developing a more powerful
in-wheel motor for use in a 4WD test car. The Colt EV will be on display at
the "2005 Automotive Engineering Exposition" to be held at the Pacifico
Yokohama Exhibition Hall, Yokohama from May 18 through May 20.
- - - - - -
Though not scheduled for production until 2010, the Colt EV platform, with
in-wheel traction motors, allows the flexibility of adding another power
plant like a standard internal combustion engine or a fuel cell to create a
series hybrid system.

 

[Guy Macon]

GM is Fuji Heavy's top shareholder

Does anyone know off-hand what percentage they own?

 

[Yousuf Khan]

According to

http://www.fhi.co.jp/about/english/outline/fact/pdf/fact_05.pdf

GM of Canada owns 20%

Interesting, Suzuki owns 2.69%

And Suzuki itself is owned partially by GM. Not sure if that's GM or GM
Canada. And why is it GM Canada that owns Subaru rather than the main
corporation?

Yousuf Khan

 

[a]

Then the
http://media.mitsubishi-motors.com/pressrelease/e/corporate/detail1269.html

may be of greater interest to you.

Now see this is how I figured hybrids would be done in the first place.
It just seemed like what better way to do AWD, not to mention being
able to do away with complicated transmission and drive-train. Why
didn't Subaru take this route?

I think they should have spent the money on this rather than developing
the Tribeca. With gas prices as they are, the last thing I want is to
buy a vehicle that sucks up even more gas. Seems to me a hybrid
Forester with in-wheel electric motors could really stir up the market,
especially with the already strong reviews of that vehicle.

a

 

[Mike Deskevich]

last i heard 20%.

 

[kstahl]

Does anyone know off-hand what percentage they own?

According to

http://www.fhi.co.jp/about/english/outline/fact/pdf/fact_05.pdf

GM of Canada owns 20%

Interesting, Suzuki owns 2.69%

 

[YKhan]

Now see this is how I figured hybrids would be done in the first place.
It just seemed like what better way to do AWD, not to mention being
able to do away with complicated transmission and drive-train. Why
didn't Subaru take this route?

There would be more unsprung weight with this kind of vehicle, which
would affect handling. You would have to find additional space inside
the wheel wells for these motors, which would affect interior cabin
and/or cargo space; at the very least you wouldn't be able to put on
those huge extra-wide bling-bling tires. You'd have to put four
electric motors in there rather than just one central one. The motors
being right in the wheel would have to be designed to absorb quite a
bit of shock since they are unsprung. You'd have to route wires to all
four wheel wells, and make sure the wires are protected against the
elements somehow.

Need I go on?

Yousuf Khan

 

[l.lichtman]

And there's more. The Toyota system cleverly feeds the gasoline engine
power and the electric motor power into a differential, which is able
to add the power from the two sources and create an output to the
wheels. This is how they get a stepless automatic transmission. If
the electric motors were in the wheels, all the power would have to be
electric, so the total electric power would be the maximum horsepower
of the car. The Toyota system is able to get by with a smaller
electric motor.

I haven't thought this through completely, but it also seems to me that
you would never be able to drive the car with the gasoline motor, and
at the same time put power back into the battery. This could be an
issue if you have run the battery down by, say, driving up a long
mountain grade, and are now cruising around town with a low battery.

 

[Carl 1 Lucky Texan]

All of those would be engineering challenges for certain. But there may
be many positives which could balance out the negatives. Lower CG,
better F/R weight distribution, more interior space options/safer cabin
design, lower/more aerodynamic profile, etc.
Those motors may not be as heavy/large as you think. Probably only need
about 4-5 HP per wheel(think, electric lawnmower motor size). Electic
motors can tolerate large excurions above the 'continuous duty' rating
for a short time and it only takes 10-12 HP to move a vehicle down the
highway at a constant 55 MPH(so acceleration is gonna require those big
'excursions' certainly). Plus there may be a way to use chain or belt
drive for the wheels and 'spring' the actual motors.
Tricky, and doubtful the finished product would be identical in 'road
feel' as a nice vehicle is today, an Element feels different than a
Jaguar, feels different than an STI, feels different than a Jeep, etc.-
but, there never seems to be an end to selling 'odd' vehicles to the
public!(especially if you bribe them to try it with a tax break!)
The main advantage I see hybrids having is , they use the current(no pun
intended!) infrastructure for 'normal' cars. Same wheels, tires,
lubricants, and fuel.

Carl
1 Lucky Texan

 

[Mike Deskevich]

I haven't thought this through completely, but it also seems to me that
you would never be able to drive the car with the gasoline motor, and
at the same time put power back into the battery. This could be an
issue if you have run the battery down by, say, driving up a long
mountain grade, and are now cruising around town with a low battery.

how about getting rid of the battery all together? do it like the
diesel locomotives do. you optimize the gas/diesel engine for one
optimal RPM (it doesn't have to be one RPM, but you can get better
efficiency if the engine is designed for a narrow range). it just sits
and runs at this rpm and generates electricity to go to the motors. no
need for lossy transmissions or anything like that. just some wires
going to the wheels. i guess you could still have a battery in there
that stores extra power for a boost durning acceleration or something,
or to catch some of the energy during braking. as another poster said,
you wouldn't need terribly big motors for this. typically a diesel
locomotive is only rated at about 2000HP or so.

granted there will be issues about larger amounts of unsprung weight,
i'm sure that's more easily solvable than all the complicated
engineering that goes into creating vicous couplers and limited slip
differentials and all the stuff we already have today.

 

[YKhan]

And there's more. The Toyota system cleverly feeds the gasoline engine
power and the electric motor power into a differential, which is able
to add the power from the two sources and create an output to the
wheels. This is how they get a stepless automatic transmission.

What do you mean they get a "stepless" automatic transmission? Isn't
that what they call a CVT? I know that the Honda system has a CVT in
it, so it's likely that the Toyota does too.

If
the electric motors were in the wheels, all the power would have to be
electric, so the total electric power would be the maximum horsepower
of the car. The Toyota system is able to get by with a smaller
electric motor.

The Toyota electric motor has a maximum power of 13HP (10kW), it's just
there to add a bit of extra spunk to the gasoline engine when the need
arises.

I haven't thought this through completely, but it also seems to me that
you would never be able to drive the car with the gasoline motor, and
at the same time put power back into the battery. This could be an
issue if you have run the battery down by, say, driving up a long
mountain grade, and are now cruising around town with a low battery.

If the batteries are low, then the gasoline engine will never be
shutdown they will keep turning until they've filled up the batteries
to a sufficient level again. Sort of like a fawcett refilling a bucket
back up that got dumped out.

Yousuf Khan

 

[YKhan]

All of those would be engineering challenges for certain. But there may
be many positives which could balance out the negatives. Lower CG,
better F/R weight distribution, more interior space options/safer cabin
design, lower/more aerodynamic profile, etc.
Those motors may not be as heavy/large as you think. Probably only need
about 4-5 HP per wheel(think, electric lawnmower motor size). Electic
motors can tolerate large excurions above the 'continuous duty' rating
for a short time and it only takes 10-12 HP to move a vehicle down the
highway at a constant 55 MPH(so acceleration is gonna require those big
'excursions' certainly).

And let's not forget that nobody actually drives at 55 mph, most will
probably be cruising at 65 to 70 mph, which would mean that you would
already be excursing over the continuous duty rating just to cruise.

Plus there may be a way to use chain or belt
drive for the wheels and 'spring' the actual motors.

Once you start moving the motors inboard of the suspension then the
need to have separate electric motors per wheel drop away. You might as
well have one motor for the whole system, or perhaps one motor per
axle.

The main advantage I see hybrids having is , they use the current(no pun
intended!) infrastructure for 'normal' cars. Same wheels, tires,
lubricants, and fuel.

Well, precisely why they are called hybrids.

Yousuf Khan

 

[B a r r y]

how about getting rid of the battery all together? do it like the
diesel locomotives do. you optimize the gas/diesel engine for one
optimal RPM (it doesn't have to be one RPM, but you can get better
efficiency if the engine is designed for a narrow range). it just sits
and runs at this rpm and generates electricity to go to the motors.

Actually, locomotives are now getting batteries.

In the past, a locomotive used the motors as generators while braking in
a process called "dynamic braking", sending the generated power to large
resistor banks in the top of the body. This power was then wasted as
heat by the resistor banks, and actually required energy to run cooling
fans.

Hybrid locomotives will now store the energy generated during braking,
and use it later to provide forward motion.

<http://ge.ecomagination.com/> Gets a flash presentation

Click on "Transportation Rail"

Barry

 

[Tom Reingold]

YKhan wrote:

There would be more unsprung weight with this kind of vehicle, which
would affect handling. You would have to find additional space inside
the wheel wells for these motors, which would affect interior cabin
and/or cargo space; at the very least you wouldn't be able to put on
those huge extra-wide bling-bling tires. You'd have to put four
electric motors in there rather than just one central one. The motors
being right in the wheel would have to be designed to absorb quite a
bit of shock since they are unsprung. You'd have to route wires to all
four wheel wells, and make sure the wires are protected against the
elements somehow.

Need I go on?

Yousuf Khan

Those sound like problems indeed, and I believe clever engineers can
solve them, over time, as they have solved many tough problems thus far.

Tom

 

[Guy Macon]

Those sound like problems indeed, and I believe clever engineers can
solve them, over time, as they have solved many tough problems thus far.

Seeing as I am one of those clever engineers, let's see if I can solve
it on the spot.

(...Thinks for a while, writing things on a quad pad...)

Got it. Here is one solution:

Unsprung weight affecting handling assumes a spring/damper
(AKA shock absorber) system with a fixed weight on the end.

Build your heavy motor/wheel assembly with an additional
counterweight in it equal to the weight of the other components.
move this weight up and down with a linear actuator so that
whenever the wheel hits a bump and moves up, a sensor senses the
movement and tells the actuator to drive the counterweight down.
The tire/road forces and the forces acting upon the spring/damper
(and thus the frame) would be the same as if the unsprung weight
was zero.

If the engineer was *really* clever, he would devise a way for
the counterweight to be a battery that can take the G forces,
thus avoiding any increase in total vehicle weight.

That's just my first shot at a solution, of course. If I was
doing this for pay I would do some experiments and simulations,
and I would take a long look at replacing that spring/damper
with an actuator, giving me an active suspension.