Disabling ABS

I'm just glad you guys aren't designing my car!... LOL

Professor
www.telstar-electronics.com

 

technically, that's not quite correct, but the conditions under which
abs outperforms a skilled driver are fairly narrow in scope and require
the abs to "know" the difference between tires, road conditions, etc.
all current abs systems "know" [afaik] is whether the wheel is locked or
not, and that's "dumb".

my experience with abs is that it's actually a very good idea on garbage
slush boxes like buicks. for cars like that, the suspension is so soft,
that sudden application of the brakes is initially taken up in the
"slush" of suspension travel, not road resistance, and the wheel can
almost instantaneously lock. as there's almost no driver feedback, the
driver doesn't know what's going on until the whole car is starting to
break loose - not good. and in this situation, i think the compromise
that is abs is on balance a good idea. with a honda otoh, it's light,
tight, and the driver can instantly feel what's going on, /way/ before
the car brakes loose. the suspension is /not/ sloppy, so the "instant
lock" phenomenon is not a feature of daily driving. in this case, i
think abs is an option, and something i personally declined when i
bought a new civic back in 2000.

 

don't you think it a high risk strategy to call yourself "professor" if
you don't know what you're talking about? and worse, don't know when to
not /prove/ you don't know what you're talking about?

 

You are absolutely correct. I have seen this demonstrated at two
performance driving schools I attented. After the instructors finished
the demonstration, the students got a chance to try it. It made me a
believer. I'm sure I'll get replies saying I don't know what I'm
talking about and the instructors didn't either. I'll give my response
ahead of time. Spend a few days and a little money and go to a
school taught by professional drivers. You will be amazed at what you
will learn.

 

the place for abs is on slush buckets where the driver has no feedback
on what's happening with the wheels, trucks where the driver has no
feedback on what's happening with the wheels, locomotives where the
driver has no feedback on what's happening with the wheels, planes
where... get the idea?

for a light & tight vehicle like a honda [this /is/ a honda group,
right?] it's only necessary if the driver can't/won't/doesn't threshold
brake.

braking distance is a function of energy absorbed. abs chops up the
absorption curve into chunks as it goes above and below threshold
repeatedly. the abs can't moderate the degree of pressure to achieve
threshold, nor can it hold it at threshold. all it can do is sense
whether the wheel is locked, release, and so on. each time it releases,
it passes threshold, each time it releases, it passes threshold. this
may be fine in reasonable friction conditions where the braking effect
between each release is considerable and the total energy absorbed
quickly accumulates, but in low friction conditions, this can introduce
considerable time delay into the energy absorption equation. try
stopping quickly in snow with abs and see where it gets you.

 

My prediction was correct. I knew it would be. IRMC. BTW: Your "Shift
Key" isn't working. PLONK! You won't stir my pot again.

 

a worthy technical analysis. thanks for contributing to the knowledge
pool by sharing your expertise.

 

Actually, its properly called Cadence braking

 

If you'd bothered to google both terms you'd know that they are both equally
accepted terms for basically the same technique.

 

not really. cadence, like abs, is where you pass /through/ the
threshold of adhesion, lock and have to release. threshold is where you
brake /at/ the adhesion limit, but don't pass through it.

 

So cadence braking is "pumping" the brake where you lock and unlock, whereas
threshold is where you constantly apply the max pressure without locking to
get the most out of the brakes, right? The technique I learned was
threshold braking, where you hit the brakes hard, when you feel the wheel
starting to lock, release the slightest amount of pressure to prevent
locking, then gradually apply more pressure to brake as you slow down,
always staying on the verge of locking. As I said earlier, a properly
performed threshold brake will outperform ABS because there is no release in
brake pressure. I still use threshold braking on my car. ABS just prevents
locking if I accidentally apply too much pressure. It's a safeguard, but I
don't depend in it.

P.S. My apologies to the poster I responsed to earlier. My response was
snotty. I'd just gotten off work and was in a rotten mood.