From: Michael Lorrey (retroman@together.net)
Date: Fri Dec 12 1997 - 06:14:27 MST
Brian D Williams wrote:
>
> From: Michael Lorrey <retroman@together.net>
>
>
>
> Theoretically, collisions between two cars identical except in mass
> tend to damage the lighter car more. (Practically, this is often
> incorrect because other, unequal factors such as design dominate.
> The National Highway Traffic Safety Administration sought to show
> the danger of light cars in recent light/heavy crash tests; the
> light cars reportedly came off better until stronger heavy cars and
> flimsier light cars were substituted.) This idealized theory leads
> some to propose that you should drive a heavier car--thus reducing
> such collisions' risk to yourself while raising others' risk
> correspondingly(70a,70b)
Thats exactly what Nader et al are complaining about. THey blame big
vehicles for the increased traffic deaths in the smaller vehicles they
hit.
> But the right answer is to make all cars
> (71a,71b)s afe whatever their weight, without putting all the
> adjustment burden on light cars. Heavier vehicles should be made
> less aggressive (Kdser 1992)--softer, less angular, more
> absorptive, with bigger ridedown distances--and the road fleet's
> mass distribution should be further narrowed, e.g. by incentives
> for replacing inefficient with efficient cars (section 11). Heavy
> lorries with slightly relaxed length limits could even be equipped
> with a highly energy-absorbing structure on the front to help
> protect any car they might hit (M. Seal, personal communication, 24
> March 1993).
>
Right answer for who??? If you want a safe efficient little car, you
should pay for the cost of the added safety. DOn't put the burden on me.
So I should sacrifice my right to good vehicle performance just so you
in your dinky little rice burner don't get flattened when you cut me
off?? Sorry, not gonna happen.
> Better control of destructive driver behaviour such as drunkenness
> is often crucial: behaviour may be up to a thousandfold more
> risk-determining than the car itself (L. Evans, personal
> communication, 1992), and only about a twentieth of crashes do not
> involve driver factors (Evans 1991).
Of course, but people who can only afford a small cheap car cause they
are too much of an alcoholic to save money for a vehicle more fitting,
or safe, or enjoyable. Don't put the burden on me for their problems.
> But as to the car, modern
> designs and materials can do far better than Henry Ford had in mind
> when, in 1926, he said that " A heavy man cannot run as well as a
> trim man. You do not need weight for strength"; (S. Abouzar,
> personal communication, 3 July 1991).
Thats accelerating performance. To disprove the usefulness of this
quote, take a 98 lb weakling in the end zone of a football field. Take a
240 lb linebacker in the opposite end zone. Have them accelerate to full
speed, and hit each other head on. Who do you think is going to be more
seriously hurt????
>
> GM's Ultralite confirms that mass per unit volume can be cut by
> more than half below the "steel plateau" level. This decoupling
> permits fuel-efficient cars to remain ultralight while combining
> roomy interiors with ample crush length, which appears to improve
> crash performance somewhat. Yet better materials and design can
> also substitute for crush length.
At what cost????
>
> Composites and other ultrastrong net-shape materials--many stronger
> than the familiarly durable but lower-grade carbon-fibre fishing
> rods, skis, etc.--would dominate in a hypercar. They would bounce
> without damage in minor fender-bender collisions: most deformations
> of carbon-fibre composite panels simply pop out again with little
> or no damage. Under severe loads, composite structures fail very
> differently than metal, so "totally different design concepts have
> to be applied", and understanding of failure modes is not yet
> mature. However, even under compressive loading--often considered
> composites' weak point(72b,72a,)"Composite structural
> elements...show high and in many cases better energy absorption
> performance than comparable metal structures" (Kindervater 1991)
> (73a,73b) Extensive aerospace experience is available from
> designing all-composite structures and aircraft (like the Stealth
> bomber and fighter) to withstand bird and stone strikes, landing
> stress, etc.
Sure one hit and you throw the entire car away. A metal body can be
easily bent back to shape at a body shop in many accidents. This is
another reason why insurance rates are going up. A higher percentage of
vehicles in accidents are declared total losses than when metal was the
norm.
>
> Light metals would also be used where appropriate, such as in
> sections of crushable light-metal foam or honeycomb for energy
> management in a serious crash. These materials, available for two
> decades (APS 1975), have a nearly perfect square-wave
> response--they squash flat, absorbing enormous energy, before
> transmitting crash accelerations--making them an ideal substitute
> for ridedown length.
>
snipping the rest of a mostly excellent post.
However, as we were originally comparing IC vs EV, and I was trying to
compare apples to apples (production IC vs. production EV) and you went
off on the hyperbody digression, which is all very good and all, but you
have yet to:
a) show any comparative studies between advanced construction,
ultralightweight small cars hitting a moose or equivalent object, with a
current Chevy Suburban or Grand Cherokee, or my brothers 1/2 ton pickup
truck. No matter what studies you cite, you still can't dispute the 98
lb track runner vs. 240 lb. football lineman collision, which is the
easiest demonstration of what I am talking about.
b) An IC with a similarly constructed body would exact the same
efficiency gains from it as an EV power train would, so using such
construction to increase the efficiency of EVs apples and oranges.
>
> Christopher Gronbeck - June 10, 1994
> Center for Renewable Energy and Sustainable Technology
> Please address comments to www-content@crest.org
>
> Yeah, I was just making it all up....
>
> Brian
> Member Extropy Institute
-- TANSTAAFL!!! Michael Lorrey ------------------------------------------------------------ mailto:retroman@together.net Inventor of the Lorrey Drive MikeySoft: Graphic Design/Animation/Publishing/Engineering ------------------------------------------------------------ How many fnords did you see before breakfast today?
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