[vox] The real problem with Toyota acceleration!

[Bill Broadley]

Norm Matloff wrote:
> On Tue, Feb 23, 2010 at 08:29:40PM -0800, Bill Broadley wrote:
> 
>> Norm Matloff wrote:
>>> When cars with ABS first came out, I refused to buy them, simply because
>>> software glitches like this would be too easy to pop up. 
>  
>> True.  Then again it doesn't seem terribly hard for ABS to be statistically
>> safer than the chance of an ABS software error making things worse.   Alas
> 
> Are you in the Northeast somewhere

26 years in Pittsburgh PA, only 10 of those driving though.

>, or at least the Sierras? 

Used to round trip through 6 7200 foot passes every weekend for a year.

> ABS
> shouldn't be much of a help in Davis.

Steering while emergency stopping can be handy, even in the dry.  Certainly
it's a bigger deal in the rain, like say today.   Since you can't individually
control the braking per wheel (unlike my mtb) there's a fair bit of increased
stopping to be had.  Sure I can threshold brake and I suspect under ideal
conditions where I'm on a flat road (and I mean FLAT, no slope to help
drainage) and I'm prepared for an emergency stop I suspect I could come very
close to matching ABS.

In a real world scenario the gains can be much larger, say the camber of the
road is off by a few degrees, you are trying to brake of course, and then
turn.  Ideal braking per wheel without ABS is pretty crude and static.

> But even accounting for the good that ABS might do, I'd rather rely on
> my own driving skills than be at the mercy of electronics that take
> away my ability to control the car.

That's certainly your choice, while cars without ABS are uncommon, at least
above er, last I checked $8k or so.   Cars with an ABS off switch aren't
unusual for cars marketed towards driving enthusiasts.

ABS systems have gotten quite a bit better recently btw.  They used to often
have less than a channel per wheel, low sample rates, actually requires
crossing the static/dynamic sliding threshold, didn't really understand car
dynamics (like weight distribution due to acceleration, braking, and turning),
etc.

The newer systems seem quite good and seems to be me a wide range of
conditions are better than a driver could possibly be.   In one particular
case I was descending from a 7200 foot pass under pretty terrible conditions,
at 5mph it was a bit slow for conditions, I'd actually start sliding towards
the inside of a corner, people would try to pass (an amusing number of them
ended up in ditches), at 10-15 mph I could hear the ABS alternating around the
4 wheels, mostly 1 wheel at a time.  I could have managed without ABS, but I
would have certainly been wishing for something less crude than a single brake
pedal  In similar situations on a mountain bike I definitely play with the
balance between front/rear braking quite a bit depending on conditions.