Computers in cars....

[Psycrow]

I can agree with some of what the "no computer" people are saying, if you get too used to ESP, active diff, trac control etc then if it fails and the car becomes more "natural" in a sticky situation, you wont know how to handle it. Saying that, when working properly (im sure the systems have a very very low falure rate), they mean you can take a car behond its normal limits. Just look at top gear a few weeks back, it was the 400BHP Evo 8 Vs a 6 Litre V12ed (600bhp??) Lamborghini - The Evo was just killing the ghini through the corners, Jeremy Clarkson was actually corering harder than the ghini with one finger on the wheel....the Evo won in the end
Anyway, bar extreme ESP systems failing at the worst time (very very unlikly + mechanical parts can fail at bad times also), id say traction control, ABS and power steering are all very good safty features of modern cars. Power steering helps old ladies corner better or helps those going a bit too fast from loosing the steering round a corner. ABS helps you break faster in the vast majority of condidtions, even when it doesnt (V wet), you still hold the ability to steer instead of the wheels locking. Traction control has no real bad points unless you are trying to tear away...which I suppose can be dangerous if at a junction, but thats why it has an off switch + you should have left more time to pull out anyway.
I find the notion that because some of the guys here rate themselves good drivers and dont think you need electonics aids, everyone else should have to do without them too. ABS saves lifes, power steering to a lesser extent also saves lives, but definatly saves arms!, traction control....perhaps more debatable but definatly bails a lot of people out, especially those with fast cars but little idea on how to drive.
Also, you can still break if the ABS system fails, its happened to me. The thing with most Electrical aids is they still have mechanical redundancies, the only bad point is people becoming dependant.

 

[Mickey_D]

Originally posted by Simon
Yeah exactly, and it only reduces the force on one wheel and not all of them

ABS is only as good as the 'control system' within it i guess.

Um, double check your car. Only high end "luxury" cars have 4 channel ABS systems. Most cars that cost less than a 5 series BMW have only a single channel, so it releases ALL brakes simultaneously.

 

[The_Dark_Side]

Originally posted by moss
From what ive read most claim that under normal conditions ABS will almost always stop you quicker but on soft or icey road conditions it can increase stopping distances, this is what ive personally found myself also.

again though,if an ABS system is cadencing many times faster than a human being can,how exactly does this make it take longer to stop on,say,ice?
surely if the abs system cannot cadence then neither can you therefore your stopping distance would be the same whether you had ABS or not?

 

[Mickey_D]

Originally posted by The_Dark_Side
again though,if an ABS system is cadencing many times faster than a human being can,how exactly does this make it take longer to stop on,say,ice?
surely if the abs system cannot cadence then neither can you therefore your stopping distance would be the same whether you had ABS or not?

Because the ABS system is binary!!

And binary actions on ice or snow equal NO TRACTION!!

ABS isn't smart enough to know what to do with ice. Humans are.

 

[CaPtBlaCk]

Originally posted by Mickey_D
Because in a perfect world, a fully functional and properly working ABS system that could interpret every situation it would be called on to perform in would cost about 2500 quid.

No matter what anyone says on here, or what experience they have with systems on cars, the ABS system on a car involves about $25 worth of electronics and $50 worth of hydraulics components and the computing power of these things can be summed up in two lines of code. And the car companies charge us $400 and up for those little add-ons.

ABS systems are supposed to be set up to handle hundreds of possible situations where a tyre may lock, but they don't have the computing power to figure out just which one of these situations they are currently under. All they do is sense that one tyre is turning slower than the others and they momentarily push brake fluid away from that wheel cylinder / caliper. These are binary systems that just react quick enough for us to "think" they are more than that. The system doesn't know if you're on snow or ice and that moderated, non-sudden movements are what's required. It just slaps the pedal back up at your foot and allows it to drop again to the point of locking the tyres. When all that was needed was a gentle nudge to let the wheel start spinning again.

When ABS systems start using a little more computing power than you'll find in a light switch, and the car companies actually start putting $400 worth of equipment in for our $400 worth of payment, I might actually begin to think that ABS is a good idea. Until then, it's a marketing gimmick that fools most people into thinking it's a safety device.

Sadly, you are way off the mark. ABS only has to determine which wheel is locking/locked, it then activates 1 of 4 solenoid valves, hardly 'hundreds of possible situations'. Cost has nothing to do with it, these systems are proven, fail safe and very reliable.

 

[CaPtBlaCk]

Originally posted by Mickey_D


ABS isn't smart enough to know what to do with ice. Humans are.

Surely ice = no grip irrelevant that you cadence brake or have the latest Carlos Fandango ABS system!?

 

[Mickey_D]

In a top of the line Jag or Merc, maybe. But your 10K quid Ford or Vauxhaull has a single chamber system that forces all FOUR brakes to release.

 

[CaPtBlaCk]

Originally posted by Mickey_D
In a top of the line Jag or Merc, maybe. But your 10K quid Ford or Vauxhaull has a single chamber system that forces all FOUR brakes to release.

No, you are wrong. The systems are generic systems from Bosch, Teves etc, the theory is the same, the operation is the same, and the end product is the same.

Single chamber!? Never heard of it. We have three channel systems on older cars which is basically 2 channels front and 1 for the rear and most modern systems are four channel which is self explanatory.

Oops edit required....

 

[The_Dark_Side]

Originally posted by Mickey_D
Um, double check your car. Only high end "luxury" cars have 4 channel ABS systems. Most cars that cost less than a 5 series BMW have only a single channel, so it releases ALL brakes simultaneously.

this makes more sense,
so your saying most cars have a single channel system which causes the brakes to release on ALL wheels even if only ONE has locked up?

Originally posted by Mickey_D
Because the ABS system is binary!!

And binary actions on ice or snow equal NO TRACTION!!

ABS isn't smart enough to know what to do with ice. Humans are.

why does it need to be anything other than binary?
apply full braking force...is wheel locked up yes/no?
if yes release then re-apply, if no then maintain braking force and recheck wheel movement in whatever fraction of a second they use.

 

[CaPtBlaCk]

Originally posted by The_Dark_Side
this makes more sense,
so your saying most cars have a single channel system which causes the brakes to release on ALL wheels even if only ONE has locked up?

It makes no sense at all when it is wrong, unless your refering to some obscure system used on a combine harvester in 1973...

 

[Mickey_D]

Meh, I'm tired of arguing.

I'll just go dig out the vid camera and go out onto my street. There's 2 inches of ice on it right now. And all the roads for the 10 miles into town. And I do 60+ mph on them no problem. And stop on them no problem.

All this in my 1981 1/2 ton Chevrolet pickup truck with its drum rear brakes, all season (note not winter) tyres, 10 years before ABS was considered on trucks, 125,000 mile old piece of junk.

I don't CARE what any magazine or car company put in print. I only care about what I can do myself. Or what my cars can do.

If and when I get my wife's car running again I'll make a video for you. I'll go out and mark off a spot on a road that is covered in ice. I'll accelerate up to 30 mph and right as I pass that point I'll slap the brake pedal to the front bumper. When the car finally comes to an ABS induced grinding halt, I'll put another mark on the road. I'll then go back and repeat the process with the fuse pulled from the ABS system.

When I am able to stop the car 10 feet before reaching that famous second marker ON FILM, maybe you'll just take my word for it......

Trust me. I've done it MANY, many times. Repeatedly. ABS is a crutch. Just like you folks say about automatic transmissions. It's for the lazy and those that just can't be bothered learning how to drive thier 1 ton, much more lethal than any gun, ballistic missiles around on public roads.


[edit] I am done with this thread. I will not be returning to it.

 

[[TW]Fox]

Originally posted by Mickey_D
In a top of the line Jag or Merc, maybe. But your 10K quid Ford or Vauxhaull has a single chamber system that forces all FOUR brakes to release.

My Ford Mondeo has a Bosch 5.3 4 Channel ABS system, I assume most other cheap cars do as well?

 

[andyfield]

Simon / Flibster I see where you are cominig from but you and Entai are both highly experienced drivers, probably the top 1% of the forums.....

For us mere mortals I think the electronic gadgets will keep us far safer than our relatively untrained driving skills, especially under unusual situations (skids / diesel etc)

Roll on even better crash protection!

 

[Simon]

It makes sense if it releases all 4 brakes, but that must be on very old systems.

I'm pretty sure the Bosch system on my car, either controls all four individually or at worst controls each circuit seperately. It certainly doesn't remove the braking force from all 4 when a wheel locks up.

mickey_D , ABS is usless in the snow and ice, so you will find that abs takes a lot longer to stop.

 

[Psycrow]

Mickey_D, I do beleive you in extreme snow the ABS might throw a wobbler releasing the wheels for longer than it should, but your point about single channel ABS is way off, most modern ABS systems are 4 channel as far as I know. Also as already said, why does it need to be anything other than a binary reaction, ABS only really comes into play in full force breaking, but even when it doesnt it just cuts the break, the reapllied force is always proportional to the amount you have the pedal down. So it even is No breaks/User Applied pressure. 1 or 0.

 

[CaPtBlaCk]

Originally posted by Simon
It makes sense if it releases all 4 brakes, but that must be on very old systems.

I cannot remember a system that worked is such away, although my experience rules out the late 70s and early 80's. In those days they had a few crazy things, so I don't think such a system actually exsisting can be ruled out all together.

 

[The_Dark_Side]

Originally posted by Mickey_D
If and when I get my wife's car running again I'll make a video for you. I'll go out and mark off a spot on a road that is covered in ice. I'll accelerate up to 30 mph and right as I pass that point I'll slap the brake pedal to the front bumper. When the car finally comes to an ABS induced grinding halt, I'll put another mark on the road. I'll then go back and repeat the process with the fuse pulled from the ABS system.

When I am able to stop the car 10 feet before reaching that famous second marker ON FILM, maybe you'll just take my word for it......

thats assuming a car fitted with ABS with the fuse pulled,performs exactly as if it didnt have the system fitted at all.
for all you know pulling the fuse may severly hinder the operation of the braking system.hence a longer stopping distance required.
you wouldnt drain the fluid from a power steering rack then expect it to be identical to the same model that wasnt fitted with power steering would you?
course not because it wasnt DESIGNED to run without fluid in exactly the same way an ABS system isnt designed to run with the fuse missing.

Originally posted by Simon
ABS is usless in the snow and ice, so you will find that abs takes a lot longer to stop.

Why?
i cant for the life of me think of any reason why that is true.

 

[Simon]

Originally posted by The_Dark_Side

Why?
i cant for the life of me think of any reason why that is true.

There is not enough grip for the ABS to work, the grip threshold is so low that the ABS removes the braking force and then it will gradually the pressure back in, the wheel will lock again and so ABS removes the brakign force again.

The result is that not much braking actually gets done lol.

 

[CaPtBlaCk]

Originally posted by Simon
There is not enough grip for the ABS to work, the grip threshold is so low that the ABS removes the braking force and then it will gradually the pressure back in, the wheel will lock again and so ABS removes the brakign force again.

The result is that not much braking actually gets done lol.

This is strange as many people’s opinions differ. For ice then nothing is really going to help. As for snow, I have never found conditions that actually made me think that the ABS was hindering the vehicle stopping safely.

 

[The_Dark_Side]

Originally posted by Simon
There is not enough grip for the ABS to work, the grip threshold is so low that the ABS removes the braking force and then it will gradually the pressure back in, the wheel will lock again and so ABS removes the brakign force again.

The result is that not much braking actually gets done lol.

still none the wiser
ABS doesnt know what surface your driving on.
if your wheel is still turning under braking then you're braking,if not the ABS system releases and tries again.
as for gradually,i was always lead to believe this happens in fractions of a second.

my understanding has always been that ABS does exactly the same as a driver cadencing does with 2 exceptions.
the ABS system becomes aware of a locked wheel infinitely quicker than a human driver could ever be,and it "pumps" the pedal faster than a driver can.

if the wheel locks up then i fail to see how a human driver can stop it either