ABS vs. 'human ABS'

[Victor Vance]

OK, here's a decent question for you guys to ponder... I've heard from a friend lightly involved in motorsports (he autocrosses his Miata twice a month) that in order to successfully master braking with ABS, you must first learn learn how to brake without ABS. Now, of course, he doesn't mean emergency braking, but competition braking, feeling out the pedal and using as much force as possible without locking the wheel... but, as advanced as ABS is today, how much will learning how to manually brake benefit usage of the ABS as opposed to a right or left foot not very experienced with manual braking?

ABS (< = >) Human ABS?
ABS + Human ABS = Best?

 

[Drifting Thunda]

Well I know that ABS can pump the brakes a lot faster than any human can, but I still think that it's important to learn to brake without ABS because you will learn the braking limits of the car much more accurately.

 

[JrunkenC]

Well, manual ABS is a very very advanced technique just because it takes practice and you need an open track/very long parking lot to learn it. I can attest tho, that ABS saves lives because it has definately saved mine. Manual ABS is definately a technique I'd like to learn one day when I have the right car and right place and plenty of time.

 

[Arwin]

I don't have ABS on my car and only noticed twice so far, both on wet roads. Ironically racing computer games has taught me to automatically feel out the brake grip limits and 'listen' for grip. ABS would have prevented me from sliding though and I think it's definitely safer.

 

[Famine]

OK, here's a decent question for you guys to ponder... I've heard from a friend lightly involved in motorsports (he autocrosses his Miata twice a month) that in order to successfully master braking with ABS, you must first learn learn how to brake without ABS. Now, of course, he doesn't mean emergency braking, but competition braking, feeling out the pedal and using as much force as possible without locking the wheel... but, as advanced as ABS is today, how much will learning how to manually brake benefit usage of the ABS as opposed to a right or left foot not very experienced with manual braking?

ABS (< = >) Human ABS?
ABS + Human ABS = Best?

Rrrrrrright. So pumping (cadence braking) or threshold braking is better when you have a system designed to be mashed to the floor and generates a pumping effect 50 times a second?

Cadence braking + ABS = Dafter than a bag of chisels.

 

[kikkoman]

i had made a topic in regards to the dangers of passive safety devices fitted to cars but i don't think anyone seriously thought about my message.
my opinion is that passive saftey devices such as ABS, TCS, even systems such as HICAS makes the driver too dependant on these automated functions to save his/her life in adverse conditions. relying on a computer as a fail safe item to save your life is a major gamble. these systems are pretty much fool proof but there have been isolated incidents that highlight issues of 'holes in the saftey net'.
take for example:
the ATTS system on top range Honda Preludes. this system acts in the same manner as a limited slip differential. it transfers a percentage of torque to the left or right driving wheels to improve handling. there have been instances where moto journos have indicated that ATTS fades and eventually fails during a sloam test. this made the steering heavy to the point of having no power steering.
another classic example of over dependance on fail safe systems is the ABS test on loose surfaces. ABS cannot differentiate road conditions and just do what they were designed to do; stop the car without locking up the wheels. but the best way to brake may be just to lock up the wheels and plough the tires into the grit.
i've been sand dune 4WDing before, 4WD equipped with permanant TCS get bogged constantly.
i think this post has made my preference is clear

 

[///M-Spec]

What your Miata driver friend is talking about is threshold braking. Since a tire generates peak grip levels right before it loses traction, it is very useful to learn how to feel when a tire is about 'lock up' under braking.

ABS will not shorten your braking distances; that was not a design goal. The fact that ABS is a passive sensing system means it cannot act until traction is already lost, so by definition, ABS will stop longer than threshold braking. What ABS does do is allow you to maintain control of your vehicle without fear of lock up the front wheels and turning you into a passenger.

For competition driving, no ABS is the fastest way to go IF you are good at threshold braking. If you are not so good, you will flat-spot a tire, which is slow and expensive. For any kind of street driving, keep the ABS. If you are average or a novice, keep the ABS.


M

 

[Scaff]

i had made a topic in regards to the dangers of passive safety devices fitted to cars but i don't think anyone seriously thought about my message.
my opinion is that passive saftey devices such as ABS, TCS, even systems such as HICAS makes the driver too dependant on these automated functions to save his/her life in adverse conditions. relying on a computer as a fail safe item to save your life is a major gamble. these systems are pretty much fool proof but there have been isolated incidents that highlight issues of 'holes in the saftey net'.
take for example:
the ATTS system on top range Honda Preludes. this system acts in the same manner as a limited slip differential. it transfers a percentage of torque to the left or right driving wheels to improve handling. there have been instances where moto journos have indicated that ATTS fades and eventually fails during a sloam test. this made the steering heavy to the point of having no power steering.
another classic example of over dependance on fail safe systems is the ABS test on loose surfaces. ABS cannot differentiate road conditions and just do what they were designed to do; stop the car without locking up the wheels. but the best way to brake may be just to lock up the wheels and plough the tires into the grit.
i've been sand dune 4WDing before, 4WD equipped with permanant TCS get bogged constantly.
i think this post has made my preference is clear

ABS is not a passive safety system, its an active safety system.

I've spent meany years training in the automotive industry and this is a common mistake to make.

Easy way to remember;

Active avoids accidents (i.e. ABS enables you to steer while braking)

Passive protects people (i.e. an airbag goes off during an accident to protect the cars occupents)


Driver aids fall into the first class (active), while airbags and vehicle crash design (programed deformation, etc) are classed as passive.

Please be aware that this is different from a 'passive sensing system' as described by M-spec. ABS is an active safety system, but its operational threshold is through passive sensing.

The general balance of opinion on both passive and active safety systems is that while they can make some people feel 'invulnerable' they have helped a huge number of people avoid accident, and when the accident has been unaviodable then minimise the injuries they have suffered.

 

[Scaff]

For competition driving, no ABS is the fastest way to go IF you are good at threshold braking. If you are not so good, you will flat-spot a tire, which is slow and expensive. For any kind of street driving, keep the ABS. If you are average or a novice, keep the ABS.


M

Quite right, when its dry.

The following is from Russ Bentley's Book 'Speed Secrets - Professional Race Driving Techniques' on the subject of ABS in competition and is quite interesting.

"I once spent a couple of days testing a showroom stock Corvette. The first day it was dry; the second it rained. Each day we ran with and without the ABS activated. In the dry I half a second a lap faster with the ABS turned off. The next day, in the rain, I was over a second quicker with the ABS on. I really learned the pros and cons of ABS during those two days."

 

[Victor Vance]

What your Miata driver friend is talking about is threshold braking. Since a tire generates peak grip levels right before it loses traction, it is very useful to learn how to feel when a tire is about 'lock up' under braking.

ABS will not shorten your braking distances; that was not a design goal. The fact that ABS is a passive sensing system means it cannot act until traction is already lost, so by definition, ABS will stop longer than threshold braking. What ABS does do is allow you to maintain control of your vehicle without fear of lock up the front wheels and turning you into a passenger.

For competition driving, no ABS is the fastest way to go IF you are good at threshold braking. If you are not so good, you will flat-spot a tire, which is slow and expensive. For any kind of street driving, keep the ABS. If you are average or a novice, keep the ABS.


M

Well, I'm quite experienced virtually with preventing locking the wheels (threshold braking, like you said, [thanks Papyrus, RIP]) so I guess once I turn 18 maybe I should attend an autocross or two to learn how to brake properly, on cheap tires of course. Anyway, he has quite a unique ABS set up on his car.... it's 'dialed back' to wait until the tire is locked 1/10 of a second or so until it releases braking force I think.... maybe so it doesn't interfere with his threshold braking?

 

[blargonator]

i say the automotive industry has to go back to its roots <8- ) no A.B.S., Power windows, A/C, power steering, and just a basic engine such as my car (1977 porsche 924). it is my first project and first car. it only has abour 100HP and its a 4 speed manual so essentially i am in control everything.

 

[Delphic Reason]

Rrrrrrright. So pumping (cadence braking) or threshold braking is better when you have a system designed to be mashed to the floor and generates a pumping effect 50 times a second?

Cadence braking + ABS = Dafter than a bag of chisels.

Agreed...

Personally, I prefer non ABS equipped cars (like mine)... I have been racing for years (autocross, rallycross) so I have learned to control the amount of pressure applied to the brakes (at least for the vehicles I have owned)... Also, there are some instances when I need to momentarily lock the wheels, and ABS just doesn't allow for that... I have never been a fan of ABS, but I do agree that it does save lives (especially for the non race savvy)...

 

[TheCracker]

I prefere threshold braking personally - you just don't get the same 'feeling' from an ABS equiped car. I would certainly recommend practising in a car without ABS before doing any kind of 'performance' driving.

 

[///M-Spec]

Quite right, when its dry.

The following is from Russ Bentley's Book 'Speed Secrets - Professional Race Driving Techniques' on the subject of ABS in competition and is quite interesting.

"I once spent a couple of days testing a showroom stock Corvette. The first day it was dry; the second it rained. Each day we ran with and without the ABS activated. In the dry I half a second a lap faster with the ABS turned off. The next day, in the rain, I was over a second quicker with the ABS on. I really learned the pros and cons of ABS during those two days."

Yea, that's a good point. But surely a pro who is an expert at wet threshold braking is still faster with no-ABS on a proper rain tire.


M

 

[Scaff]

Yea, that's a good point. But surely a pro who is an expert at wet threshold braking is still faster with no-ABS on a proper rain tire.


M

I think it would very much depend on the driver (I mean Russ Bentley may not be a household name worldwide but he is a damn good driver) and the car.

With regard to drivers, some hate wet driving and some such as Senna loved it. I mean Senna was just amazing in the wet, very few could touch him when the rain started.

With regard to the car, if it has good braking 'feel' with a lot of steering communication about the level of grip remaining then without ABS may be the better move; but if you cam't be sure about the level of grip remaining when braking then threshold braking becomes a damn sight harder and ABS may prove to be faster. Confidence issue as much as anything.

 

[Scaff]

I prefere threshold braking personally - you just don't get the same 'feeling' from an ABS equiped car. I would certainly recommend practising in a car without ABS before doing any kind of 'performance' driving.

Cracker, this would depend on the car and when the ABS has been set to interven.

If the ABS is over-eger (a lot of family orientated cars are set like this) then I quite agree, however more performance orientated cars will only apply the ABS fully once slip has been detected. The 'feel' of the braking threshold has not in this case been effected by the ABS, as you are beyond the threshold of grip before the ABS cuts in.

One very interesting thing about ABS is that most people are not used to how it works (many only ever emergency brake once - during there driving test) and as such people will back off the brakes when the ABS judder starts. This leads to an increase in straight line braking distance (over non-ABS) and possiable loss of control is the car is changing direction.

This was the main reason why 'Brake Assist' systems have become popular over the last few years, they apply maximum brake force (subject to ABS limits) when the brake pedal is hit above a certain velocity. The maximum braking is maintained until the driver fully removes pressure on the brake pedal. This allows an in-experienced (at emergency braking) driver to brake with near maximum effect, even if they lift slightly when the ABS kicks in.

 

[LoudMusic]

I am under the impression that you can't mix the two. If you have ABS you're supposed to slam it to the floor so ABS can kick in. Otherwise you're not stopping as quickly as you can.

Personally I prefer non-ABS. But I also prefer a manual transmission over an automatic. But not everyone is like me and most people don't have good "skills" when driving. ABS is a good thing to have on the road, but it's not my choice.

 

[producepete]

ABS is a wonderful invention. It's better than manual braking.

 

[skip0110]

Many only ever emergency brake once - during there driving test

Really??

 

[Scaff]

Really??

Yep really, most average drivers only ever emergancy brake during their driving test (in the UK). Very, very few people ever take advanced driver training or re-train to keep up skill levels. As a result the next time they may need these skills is when they are in a situation that is getting beyond there control.

Lack of training then leads to panic and the emergancy stop that may well have minimised or avoided an accident is applied to late or incorrectly.

Remember I'm not talking about braking hard here, but the average motorist in a situation where they have to bring a car to a conplete stop, as quickly as possiable, while avoiding a potential incident.

 

[RyosukeFCDS]

Personally, I'll never competitively drive with ABS active, or traction control, or any of that rubbish. It's intrusive and annoying.

 

[Azuremen]

Tis true what you say, it is intrusive.

However, most people cannot threshold brake period, and those that can, usually cannot maintain the focus in an emergency. You've got to be albe to kill your panic reaction and impulse, which is kinda hard to do.

I never had a real panic reaction, so well, yeah. But the braking got me outta one thing - avoiding a dog in the road - into another - getting rear ended by a driver that didn't have the awareness or skill to stop...

But yes, human braking, on dry stuff anyhow, is better. On snow... ABS can be a god send, even if you know what you are doing, cause snow and ice are very random about gripping and then suddenly getting much slicker...

 

[Scaff]

Quite simply put in the wet/snow/ice a human being can not react and act as quickly as a well set-up ABS system. It is simply not possiable.

In the dry its a different matter.

 

[Azuremen]

Pretty much true.

Combine that with irregularties in the surface which lead to different tires having various amounts on traction, and no human can properly handle it.