microcode, compilers, and supercomputer architecture

From: Merle K. Peirce <at258_at_osfn.org>
Date: Mon Apr 5 18:31:10 1999

I'm not sure I buy the arguement. The main reason is this: The last 30
years of wonderful safety improvements have unfortunately left us with a
population of drivers who are incompetent. Some might say that they are
the transport analogue of Windows users.

Apparently, ABS works well for large vehicles, although the first
incarnation was a nightmare. Finally they seem to have it right. I tend
to be suspicious of anything that is federally mandated.

The brakes themselves are not bad, however, the story that when the ABS
fails the car brakes normally is not always true. A recent discussion
thread of this on Rovernet centred around an incident where the failure
was complete, yet intermittent.

The problem is that drivers will often imagine the brakes can do the
impossible and they drive faster, reduce their following distances, brake
harder and crash. It is in this context that ABS is less than total
success. This is also the behaviour drivers of many four wheel drive
vehicles. Safety equipment is no substitute for prudence and discretion.
The greatest safety comes from conducting yourself and your vehicle so
that things like ABS never have to come fully into play; when they do,
then they provide an extra measure of safety. A trained and capable
driver can do wonders with a marginal vehicle, but all the wonderous
safety equipment in the world can't make up for a fool at the wheel.

I spent over 25 years in public transport, so I do have the experience
and ill temper to bear me out. I also favour the classic British car, so
ABS is rather moot for me. The ideal car for me might be an ICL with
large wheels...

On Mon, 5 Apr 1999, bluoval wrote:

> Well, since we're on the topic of ABS brakes....
> 1) ABS has sometimes, in the past, been used in cars and (mostly) trucks only
> for the stability of the system and not for the reduced braking distances. Many
> vehicles w/ rear-only ABS use it so the rear of the vehicle doesn't fish-tail in
> a emergency brake situation. Most manufacturers (if not all) now implement 4
> wheel ABS, which significantly reduce braking distances.
>
> 2) even if the ABS system fails it still works just like non-ABS brakes. unless
> the vacuum (power assisted) system fails or the brake line is cut, or (very
> unlikely) the piston sticks open, the brakes will work just fine.
>
> 3) w/ a properly functioning ABS system, there is almost no way a person can
> 'out-brake' it with the same size and type brake system (same number of pistons,
> size and compound brake pads, same brake fluid, same size rotors and calipers
> ect..) The ABS 'pumps' the brakes at a speed that humans could not possibly
> acheive. this is why they are computerized. sure, I can stop a car faster than
> any ABS system, and I'm sure you could easily do it too, but not as safe (brick
> wall, tree, ect.)
>
> 4) if you really want to drive a car w/out ABS *and* make it safer than one w/
> ABS, there are a few things you should do besides training ( that's a given, and
> about $2K min.). Spend a couple $K to increase all component sizes, get real
> sticky pads, get wider sticky tires and pray you don't lock-up. oh, and don't
> slam on your brakes in a non-ABS car... *SCREECH*, a couple of 360s and crash.
> its happened to me, xcept for the crash...i think i was lucky.
>
> 5) You stated below the reasoning of not wanting an ABS equipt car. Here's my
> response: There is documentation about the ABS brakes, how do you think
> mechanics fix them? Go buy the book. About the failure bit: sure, anything can
> fail! the airbags (u want those in your car, right?), the tires (these too?),
> headlights (?), seatbelts (!).. i think you see my point. I answered the last
> reason above. It is very unlikely that ABS brakes will fail. And the part
> about skill.... have you ever watched NASCAR? Highly trained guys there...crash
> all the time! F-1 races? there too! NASCAR doesn't allow ABS, and there have
> been a few rule changes in KART that i haven't kept up with so i can't comment
> about that.
>
> So basically, if you want to be ABSOLUTELY safe don't drive, fly, walk, run with
> scissors in you hands, tilt your chair back too far, or even leave the house.
> wait tornados... don't leave your basement.
>
> All kidding aside, ABS is probably one of the best safety features in any car.
> If you are buying one new or used, don't leave the lot without it. Airbags
> too! They react and act faster than you can.
>
>
> Tony Duell wrote:
>
> > > We don't need to bring moralizing into the discussion. Most of us already
> > > relegate a lot of life's decisions, including some life-critical ones, to
> > > computers every day.
> > >
> > > Or are you the kind of person that refuses to buy cars with antilock brake
> > > systems?
> >
> > Well, I don't drive yet, but when I do, I sure as hell won't have a car
> > with ABS.
> >
> > The reasons are that (a) I am not going to trust my life, and the lives
> > of others to an undocumented system that could possibly fail, (b) a good
> > driver can stop a car in a shorter distance than an ABS system can under
> > some conditions and (c) if it does fail you have to use the brakes
> > differently than you do with a working ABS system.
> >
> > No thanks. I'd rather trust my skill (and thus have to learn to do things
> > properly) than trust a microprocessor.
> >
> > >
> >
> > -tony
>
>

M. K. Peirce
Rhode Island Computer Museum, Inc.
215 Shady Lea Road,
North Kingstown, RI 02852

"Casta est qui nemo rogavit."
              
              - Ovid
Received on Mon Apr 05 1999 - 18:31:10 BST