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About the only significant electronic development in cars of the last
decade is the widespread fitting of stability control. Like ABS, this
system can prevent many crashes. In fact, German statistics show
that cars fitted with electronic stability control are involved in fewer
accidents.
by JULIAN EDGAR
What’s happened to
Electronic
Advances In Cars?
Car manufacturers seem to have lost the plot.
Instead of cramming new cars with useless
electronic gadgets, they should be using
electronic technology to improve efficiency
and reduce fuel consumption.
I
T’S A SNOW-JOB: we’re being sold
purported advances in car technology that achieve little real benefit. In
fact, instead of being better off, we’re
paying in cash and fuel consumption
for a plethora of unwanted and unneeded gadgets: in-car entertainment,
climate control, electric seat adjustment with memory, active steering,
electric handbrakes, parking proximity sensors and auto-dimming rear
12 Silicon Chip
vision mirrors. They’re being foisted
on us to disguise the fundamental lack
of design progress being made in cars
and we are paying for these “advances”
in higher fuel consumption.
How so? Well, how much do you
reckon a seat that contains no less than
six electric motors weighs – some quite
hefty in size? Or a sound system that
includes a CD stacker, eight speakers (including a subwoofer) and two
amplifiers? It’s not even possible to
physically pick up the wiring loom
of a modern car – it’s too heavy. And
how much do all these gizmos cost to
develop?
You can be sure that if this stuff was
taken out and the resources devoted to
better engineering the basics of the car,
you’d be paying less and going further
on the same tank of fuel.
Yes, there have been significant
electronic breakthroughs in car design.
Trouble is, all but one happened about
a decade ago.
Engine management
It’s well over 15 years since we
first saw “family-priced” cars with
electronic engine management. Along
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with its ability to reduce exhaust emissions, improve starting, power and
economy, and allow the widespread
introduction of other technologies like
turbo-charging, engine management
was a genuine breakthrough.
But contrast that with electronic
throttle control. These days nearly all
cars are sold with a throttle that’s run
by an electric motor. You put your foot
down and a pair of potentiometers relays signals to an ECU that checks them
for compatibility with one another and
then decides how much throttle it will
actually give you. The latter depends
on engine temperature, the torque
output of the engine at those revs – a
whole bunch of internally-mapped
stuff. Gee-whiz indeed!
But so what? Apart from integrating more smoothly with the cruise
control and allowing the system to
close the throttle on you, what’s the
huge benefit? In fact, many people
complain that the throttle response
of these systems is dull – one of the
original aspects that engine management helped improve over points and
carbies! And the engineers who design
and then map the electronic system
spend literally years on the project,
including time on esoteric aspects like
anti-surge control that stops incompetent drivers kangaroo-hopping.
What if they spent that time and
Where is the progress in current cars? This 12-year old Falcon engine has
direct-fire ignition, a dual-length changeover inlet manifold, knock sensing and
full engine management. Under the bonnet of a current Falcon you’ll find a lot
more power but in terms of electronic and mechanical advances, just variable
camshaft timing and electronic throttle control. The pace of improvement in
engine electronics is slowing to a near standstill.
money developing active aerodynamics instead, using just the same sort of
actuators and control logic to reduce
the drag of a car by 25-30% at highway speeds? Or what about infinitely
variable intake manifolds, rather than
the archaic two-step long/short runner
changeover that’s now common? So
forget kangaroo hopping: how about
better fuel economy?
Or take engine knock sensing. The
ability to run ignition timing as advanced as possible for the conditions
of fuel octane, intake air temperature
Honda Insight: A Brilliant Concept
Although a complete sales flop in
Australia, the 2001 Honda Insight
is yet to be bettered in terms of
design. It addressed nearly
every concern expressed in this
article. The aluminium-bodied
hybrid used a lean-burn, 1-litre, 3-cylinder petrol engine
featuring variable valve timing
and developing 56kW at 5600
RPM. Peak torque was developed at just 1500 RPM.
A 10kW electric motor – which
also doubled as a generator and
starter – was sandwiched between
the engine and the conventional
5-speed manual transmission and a
144V NiMH battery pack was fitted.
The drag coefficient was just 0.25
and the total mass only 827kg. Twin
airbags and ABS were standard.
For the on-line magazine “Auto
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Speed”, I drove an Insight on an
interstate trip of 3500 kilometres,
completed in just four days. Driven
normally at the open-road speed
limits, the car turned in an average
of 3.6 litres/100km, the best real
world economy of any car ever sold
in Australia. The official highway
figure was an astonishing 2.8
litres/100km! The sprint to 100km/h
took about 12 seconds.
And the negatives? A retail price
of nearly $50,000 and poor packaging that saw most of the load area
of this two seater taken up by a
battery/electronics box.
December 2006 13
Remember Those Big Old “Yank Tanks”?
It’s not very many years ago that
we all used to laugh at sixties “Yank
Tanks”. They were enormous vehicles, vastly overweight, with simple
suspensions and huge V8 engines
to drive their bloated forms.
In fact, to take one example, let’s
briefly look at the pictured 1963-65
Buick Riviera. Despite having only
two doors, the Riviera was no less
than 5.3 metres long and weighed
1800kg. Its huge pushrod V8 engine
could be optioned up to just less
than seven litres with a peak power
(measured in SAE units) of 253kW.
Standard transmission was a DualPath Turbine Drive automatic. It was
a huge, heavy, over-powered barge
which probably drank fuel at the
rate of 25 litres/100km.
Today, many of us are driving
cars that, philosophically at least,
are not much different. Take the SS
Commodore. It’s 4.9 metres long,
just 40cm shorter than the Riviera,
and it weighs 1650kg or just 8%
less than the sixties Buick. And the
motor is now six litres and 260kW,
although its fuel consuption is con-
and engine load is of great benefit – it
provides optimal power and economy.
Trouble is, that technology was available in family cars well over a decade
ago. The same goes for “direct fire”
ignition, where troublesome distributors and ignition leads made way for
multiple coils. Even ABS – a worthwhile gain to be sure – was being
sold on Australian family cars over
10 years ago.
In fact, about the only really worthwhile breakthrough I can see in the
last decade is the fitting of electronic
stability control, which has the potential to prevent many accidents. In
fact, German statistics show it is doing
just that.
The hoopla
You’d never believe from watching
the ads and listening to the salesmen
that every new model is anything but
a grand exposition of cutting-edge
technology. Sure, since the 1950s in
the USA (when annual styling updates
were introduced), car manufacturers
14 Silicon Chip
siderably better than the old Buick’s.
So huge, heavy cars with enormous V8 engines aren’t something
from an American car museum –
they’re here now and available at
your local dealer.
We laughed at cars like the Buick
have been selling cars on the latestis-best philosophy. But now it’s electronics that is underpinning much of
the hype.
“Have you seen our twin DVD
screens, sir?”
“Do you realise this car has auto
windscreen wipers, madam?”
“This auto transmission now has six
ratios and Adaptive Logic Control”.
(No sir, I don’t know why it needs
that many gears when in fact this year
the engine is larger and has an even
broader torque curve than before.)
“Madam, this seat has three memories – and oh no madam, it’s not just
the seat! When you press the button it
also adjusts the external mirrors and
the position of the steering wheel to
your preferred settings.”
“That’s right, sir, the steering column now has two electric motors in
it”.
“Have you seen the rear window
blind, madam? It rises and falls at the
touch of a console button. And you
know what? It automatically drops
because they were much larger
than was necessary, therefore had
far greater weight than was needed
and as a result, used huge thirsty
engines to push along that weight.
So are today’s big V8-engined cars
any different in basic concept?
down when you are reversing!”
This parade of smoke and mirrors
disguises the fact that the rate of progress in the fundamentals of car design
– fuel economy, packaging and performance – has over the last decade been
disgraceful. Fact: my 1994 EF Falcon
5-speed manual gets better real world
fuel economy than a current Falcon.
Fact: it also matches the current car in
acceleration to 100km/h. Fact: most
SUV-type vehicles have incredibly bad
interior packaging that sees 15 and 20
and 30-year old cars look amazingly
spacious. (Just sit in a 1960s Austin
1800 or look in the load area of a 1980s
Holden Camira wagon.)
Yes, in an accident I’d prefer to be in
a current car – even though that same
old EF Falcon has a driver’s airbag
and ABS.
Toyota Prius
So what about that touted technological masterpiece, the Toyota Prius?
Well, the best that can be said is that
at least Toyota tried.
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The car is aerodynamic, it has
power (and bottom-end torque) appropriate to the real world and it is
space-efficient. But the shortcoming
screams to anyone with even only half
an ear on the automotive world: batteries. The NiMH battery pack is heavy
(the Prius, for its external size, is one
of the heaviest cars on the road) and
requires such a huge amount of energy
to produce that it’s doubtful whether
the energy saving in fuel over the life
of the car outweighs the production
energy input. And in energy/kg terms,
it has almost no capacity and is certain
to have a life shorter than the rest of
the car.
In fact, it could be argued that the
Prius could be an even better car without the heavy battery pack and instead
with bodywork made from aluminium
and powered by a very small turbocharged engine – say a 3-cylinder of
the type first widely used in Japanese
Kei class cars of 10-15 years ago.
Diesels
Diesels have been much in the news
recently and the specific power and
torque outputs of passenger car diesels have rocketed. They also achieve
significantly better fuel consumption
than petrol engines – although the
major upsizing of diesels now being
fitted to passenger cars is rapidly eroding that advantage.
But since these more efficient diesels run electronic control, doesn’t
that shoot down my argument in
flames? No! Most of the technological
breakthroughs in diesel fuel systems
have been purely mechanical, espe-
The gizmos being packed into today’s cars disguise the lack of real progress
being made in economy, packaging and performance. From 10-way power
electric seats to multi-screen DVD players, dual climate control, electric
handbrakes and auto-dimming rear-vision mirrors, it seems that electronics
is now being used in complex gadgets designed primarily to just entertain and
amuse.
cially the engine-driven fuel pumps
designed to develop very high fuel
pressures. Apart from a high voltage
system used to operate the high-pressure fuel injectors, the electronic architecture of the system is very much
like a late eighties petrol management
system. And anyway, trucks have had
electronically controlled diesels for 20
years or more.
Missed opportunities
So where should the electronic and
mechanical advances have taken us?
For starters, it’s bizarre that engine
management systems are still running
pretty well the same air/fuel ratios that
they always have. If you burn less fuel,
you get better fuel consumption – but
cars still use a 14.7:1 air/fuel ratio (at
least the madness of high-load 12:1
and 11:1 air/fuel ratios has just about
ceased in new cars). Running leaner
air/fuel ratios has emissions as well as
economy significance – the output of
oxides of nitrogen skyrockets. So, how
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December 2006 15
ment system is programmed to adapt
itself to the appropriate fuel – whether
that’s petrol, alcohol or any mixture
in between. In Europe, half of all new
cars are diesels.
And if a DVD screen is obligatory,
why not use it for the rear vision and
not just when reversing – ie, to completely replace the mirrors and rear
window? In addition to reducing the
solar radiation into the cabin input
(and at night, that of following cars’
headlights), the drag-inducing exterior
rear vision mirrors could be dispensed
with and the rear of the car far better
tailored for low drag. (Many don’t realise that the shape of the back of the
car is more important than the front in
reducing aerodynamic drag.)
Losing the plot
At highway speeds, most of the fuel is used to push the car through the air. But
after the rapid developments in the late eighties, aerodynamic development
has now stalled. Drag coefficients have barely changed in 10 years, let alone
developments like actively-controlled aerodynamics which has the potential to
dramatically drop open road fuel consumption.
to solve the problem of high oxides of
nitrogen emissions when running lean
air/fuel ratios? That seems like a good
research project for the engineers –
perhaps for those engineers currently
working on the software control of
the next model’s 10-way power seat
design.
Aerodynamics has stalled. At highway speeds most of the petrol that
your car burns is used to push the car
through the air.
In the late eighties, manufacturers
(finally) recognised this and moved to
“slippery-shaped” cars. Aerodynamic
drag coefficients dropped in just a few
years from mid 0.4 figures to mid and
low 0.3 coefficients. But since then
there has been almost no change.
In fact, most manufacturers now
don’t even bother stating the drag coefficients of their new cars – let alone
the total drag found by multiplying the
coefficient by the frontal area. And the
bizarre thing is that the poor internal
packaging mentioned earlier is not the
result of sacrifices made to produce
low-drag cars – cars (like SUVs) with
the poorest drag figures often have the
poorest packaging!
The number of production models
with electronically-controlled moveable aerodynamic surfaces can be
counted on the fingers of one hand,
yet such an approach has the potential
16 Silicon Chip
to substantially drop open road fuel
consumption without any aroundtown disadvantage.
The advances in electronics are also
not being employed with any kind of
engineering rigour. LEDs consume less
electrical power, have faster light-up
times and effectively never fail. You’d
expect then to see LEDs being used on
– at least – all rear lights and indicators
(as in fact they are on most new trucks).
But on cars, that’s the exception not
the rule. Instead, manufacturers have
moved to using coloured LEDs for
instrument panel and foot-well illumination because then they can talk
about the “cool blue” lighting!
Solar cells? They’ve improved in efficiency at the same time as costs have
decreased. So why don’t many cars in
our sunny land use solar cells to keep
the battery topped up and the internal
fan ventilating the cabin when the
car is parked? Mazda once sold a car
with this feature on the local market
but otherwise there’s been no sign of
such lateral thinking.
Alternative fuels? Almost zero
progress, with LPG system technology lagging decades behind petrol
fuel injection. In Brazil, 30% of new
cars are able to run on either petrol
or alcohol, with the alcohol made
primarily from locally-grown sugar
cane. In those cars, the engine manage-
However, the problem is far more
fundamental than not applying some
obvious technologies: simply, car man
ufacturers have lost the plot.
They pack in more and more trivial
and irrelevant equipment, making cars
heavier. Even a small car these days
has a mass of 1250kg or more. To cope
with the increased weight, they fit
larger brakes, heavier suspension and
wider tyres. The wider tyres increase
rolling resistance and accelerating the
heavier mass requires more fuel, so
producing more pollutants and to a
large extent decreasing the effectiveness of tighter emissions standards.
To be market competitive, apparently the next model is always required to
have even more equipment and more
power, so the cycle continues.
It seems no manufacturer ever steps
back and lays out the criteria for the
functionality of a car, ignoring what
others are doing and simply trying to
achieve the best outcome.
The mind boggles at the thought
of what innovative and original car
designers like Ferdinand Porsche
and Alec Issigonis would now be
able to do with the exotic materials,
CAD/CAM design techniques, wellinstrumented wind tunnels and the
electronic control systems available
to today’s designers.
One thing’s for sure: they wouldn’t
be designing 1.8-tonne cars with the
worst interior packaging in automotive
history, hugely powerful and equally
thirsty, and loaded to the gunwales
with complex electronic gadgetry
designed primarily to just entertain
and amuse.
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