[Shambles]

My mistake - I was probably drinking thinking about traction control...

[Dazzler]

My mistake - I was probably drinking thinking about traction control...

Geez Steve .. Colouring in your owners manual like that might devalue your car...

[Shambles]

^-- Gee I didn't consider that 

I actually coloured the screen, so it's easier to wipe off with some spare spit that Alan keeps in his car

[Dazzler]

 

[Asterix]

I collected the car from the garage this evening; the mechanic seems to be convinced it is 'the abs kicking in' and not a fault.  I asked about the grinding noise and he said that all cars make that noise when the abs is working.  I said I have never experienced a noise like that before and he repeated that all cars do it.  His explanation for the brakes not working is 'the car will not stop on ice even with abs'. 

Hi Katy.

To prove his statement, you should take your car to a place where you can try out the ABS function.

Find a road or big parking lot where you can get the car to 30 mph and then press the brake pedal as hard as you can and don't stop doing that until the car stop moving.

If he is right, you should experience exactly the same as you did on the road. Same noise and same behaviour.

You need, ALL drivers need, to know how the ABS works, so they don't panic when the day comes they need it.

[Phil №❶]

Good advice, I must take it.

Question,

Does a car stop in a shorter distance with ABS as compared to an experienced driver that locks the brakes, but regains control by reducing brake pressure. 

[Asterix]

One from my previous work was a race car driver in DTC (Danish Touringcar Championship) and these guys would tell you that they at any time could brake at shorter distance without ABS.

I think they're right.

They can keep max pressure all the time, where the ABS change the pressure constantly.

[Surferdude]

Phil, before I left Goodyear we did some tyre testing at Winton Motor Raceway in Victoria in conjunction with Ford Australia development engineers using among other cars, an XR8 test hack which Ford used to try different things. They could activate and deactivate the ABS at will for testing purposes.

Whether wet or dry, non ABS pulled up more quickly.

But here's the qualifier. When you are testing, or racing, you are totally alert at all times and when you go for the brakes, you generally KNOW you're going for the brakes so you are mentally prepared for applying just the right amount of pressure and totally alert to the need to ease off slightly as the wheels start to lock up.

On the road, in traffic, things which happen are unplanned and no matter how "alert" you may think you are, it's not the same.

So, in my opinion, ABS is a safer option on a road car and most likely will pull you up more quickly.

Which doesn't mean yuo can allow yourself to get too close to the car in front.

[Phil №❶]

Well put Trev,

Yes, testing is an entirely different ball game. As we can't turn ABS off, it is still theoretically possible to stop shorter than ABS would in an ABS fitted car, by maintaining the correct pedal pressure and thus not activating the ABS.

Question 2

Assuming an unexpected obstacle appears on the road and you react by hitting the brakes and ABS activates, is it better to let ABS do it's thing or try to get control back and what does it take to get that control.

[Surferdude]

In my experience, just the same as in a car without ABS. Gently ease of the pedal until the ABS stops chattering and then maintain as heavy a pressure as you can without locking up again. It takes practice and each car is different.

[FatBoy]

My understanding of ABS is that it releases the brake pressure and then reapplies it over many times in a second to stop the wheels from locking up.  It does this much faster than a human being could.  So if the ABS does start to operate in a situation, then let the ABS continue it's job.  ABS combined with ESP should (repeat, SHOULD) enable you to control the car while decelerating with your foot firmly on the brake.

To regain control of the car in this case you would have to release brake pressure (which would stop the braking effectiveness) and then reapply a little less pressure (therefore you aren't braking as hard).  Trev will hopefully provide some better input and understanding of the system if I am either wrong or right.

My opinion is that if ABS is used to stop a 100 ton aircraft fully laden with fare paying passengers on a wet runway from 300+ km/h to stop, then it is good enough for me.

[Phil №❶]

Which is why I asked the question, to regain control requires less or no braking briefly and I wanted to know which is the better option. I haven't ever had to use it, so I honestly don't know. If it means avoiding a child or animal, well 

Adding to this, Trev's previous response about the difference between surprise and testing, it would probably be best to stay with ABS, in accordance with your response too.

[Surferdude]

What you say seems right to me fatboy, it's just that in practice the chattering, noise and pulsating brake pedal put people off  if they're not used to it.

And in answer to Phils' last question, that's a call which has to be made by the driver, in an instant.

[rustynutz]

I'm in agreement with what Jamie said....
You're better off keeping your foot planted and let the ABS do it's job. Easing off the brake and re-applying is just gonna extend your stopping distance.

The beauty of the ABS is that you're still able to steer while braking, great for the average mug like me...

[Doggie 1]

During police driver training, the ABS is switchable so we can be taught braking with or without it.
For an experienced driver, non-ABS will stop quicker every time, whether on dry or wet bitumen or on gravel, etc.
The issue is, most people aren't taught advanced driving skills so for the majority, ABS is better.
The maximum braking power on a non-ABS car is available just prior to lock up. So when braking in a non-ABS car you have to know when lock up will occur and brake to just short of that, if that makes sense.
If lock up does occur, then you need to release just slightly to unlock and then maintain that braking pressure.
I saw it time and time again that non-ABS would stop in substantially shorter distances with experienced drivers who knew how to brake effectively.
If however, you are using ABS, you need to plant the foot as hard as you can and keep it there, letting the ABS function do its job.
If you ease off the braking pressure in an ABS-equipped car, you will lengthen the braking distance.
And I agree that all drivers need to know what ABS feels like so it is good idea to practice.
And in a car equipped with ABS & ESP it takes practice to get used to the fact that you can keep the foot firmly planted on the brake pedal while it is "chattering" away and steer to avoid obstacles at the same time.
It is counter-intuitive so requires plenty of practice to get used to.
Knowing how to brake effectively is one of the main reasons why police are able to "stay with" cars that are much more powerful in a high speed pursuit situation, as most people will brake early and in such a way as to destabilize the car.
If you know how to brake and you know your car, you are able to brake much later on approach to, say, an intersection and then apply maximum braking without locking up.
So what they might gain on the straights, the baddies lose on the corners. 
Much the same as race car drivers will maintain maximum momentum as long as they can and brake effectively and for a shorter distance on approach to bends, corners and obstacles.
If you get to the point of lock-up, then you don't have braking control. The car is just skidding and braking distances increase.

[Phil №❶]

I am pretty much aware of the maximum braking just b4 lock up and all that stuff, but a novice when it come to ABS. This is the first ABS car we've owned.

I learnt something today,  everyone 

I've learnt something today...

Me too. I expected ABS would always be better because it can control each wheel independently. I've not had ABS before either. Nice to know that all learned braking experience from before will still hold up in an emergency, assuming you don't panic if ABS does intervene.

[Phil №❶]

I agree Pip, the thing is, I more than likely would have reacted to the sound of the ABS before today. I'll try it in 6 months time,,,, when it rains.

[Doggie 1]

I agree Pip, the thing is, I more than likely would have reacted to the sound of the ABS before today. I'll try it in 6 months time,,,, when it rains.

Or find a gravel road or car park Phil and have a play, with steering wheel held straight plus turning whilst braking.
It can be fun. 

[AlanHo]

The problem out on a public road (as opposed to a test track) is that there is likely to be sudden changes in the road surface in the path of the car and differences in texture, potholes, wetness, ice etc on each side of the car.

Even an expert driver will find it impossible to apply the optimum braking force to each wheel individually, and maintaining a constant force on the pedal will of course not take into account sudden variations in road surface.

This is what ABS does - it monitors the skid threshold of each wheel separately and ensures that the average driver in an emergency gets the maximum brake efficiency.

The new 2012 i30 has an Emergency Brake Assist which applies maximum braking when it detects an emergency braking situation. It responds to a sudden and hard application of the brakes by the driver – who might then not apply enough foot pressure on the brake pedal for maximum braking.  The car also has Vehicle Stability Management which is linked into the ABS, ESC and the steering system to achieve maximum stability under emergency situations when, for example, there are differences in the coefficient of friction between one side of the car and the other.

I was fortunate to have attended the pre-launch demo at Silverstone and be given the opportunity of testing these systems under extreme conditions. After that experience I am content to put more trust in the car than in myself being able to react optimally in a sudden emergency.

[Shambles]

This is what ABS does - it monitors the skid threshold of each wheel separately and ensures that the average driver in an emergency gets the maximum brake efficiency.

... when coupled with the EBD^* system.



^* Electronic Brakeforce Distribution

[Phil №❶]

Do we all have EBD, I thought EBD meant Enormous Big Deal

[Doggie 1]

Even an expert driver will find it impossible to apply the optimum braking force to each wheel individually, and maintaining a constant force on the pedal will of course not take into account sudden variations in road surface.

I hear what you're saying but I don't agree with that.

This is what ABS does - it monitors the skid threshold of each wheel separately and ensures that the average driver in an emergency gets the maximum brake efficiency.

I agree with that bit.

I was fortunate to have attended the pre-launch demo at Silverstone and be given the opportunity of testing these systems under extreme conditions. After that experience I am content to put more trust in the car than in myself being able to react optimally in a sudden emergency.

I was invited by Holden to a drive day with a range of their new cars at Barbagallo Raceway where we caned the cars with traction control on and off and were able to undertake some quite violent driving manouvres which demonstrated the effectiveness of ABS, EBD & ESP.

They are great advancements in vehicle safety and good systems to have.

But when they were switched off and people were told to do certain things (like violently turn the steering wheel at speed), they lost control of the car. Myself and one other person there (plus Holden's instructors) did not. We had some nice power slides though. 
In fact one of the instructors came up and asked me who I worked for after the event. 

I say that to highlight the fact that training is a good thing, whether using safety systems or not but for most people, most of the time I believe they are a good thing.

The thing that stuck in my mind from that day was that all of those brand new cars that copped a real caning that day would have been prepared and on-sold to unsuspecting buyers as "factory demos."  I wouldn't want one.

[rustynutz]

I would recommend doing a "Defensive Driving Course" if for no other reason than to find out how your car performs with ABS & ESP. 

I did one a couple of years back and it was worth every cent....

 

[Doggie 1]

 

[Dazzler]

I would recommend doing a "Defensive Driving Course" if for no other reason than to find out how your car performs with ABS & ESP. 

I did one a couple of years back and it was worth every cent....

 If it only cost a few cents I would do one too 

[rustynutz]

Only cost me 9,900 cents, Daz.... 

[Dazzler]

That is pretty good  I better start saving .. or apply for a loan 

[Doggie 1]

That is pretty good  I better start saving .. or apply for a loan 

   

We all know you're loaded Dazz, living in that mansion. 
Are you sure you aren't related to Princess Mary of Tasmania?
http://en.wikipedia.org/wiki/Mary,_Crown_Princess_of_Denmark

[Mike SX]

We all know you're loaded Dazz, living in that mansion.