ABS or w/ABS

it depends .
usually , during wet tiem the wheel can lock up easily . when u do not have abs , the grip is almost none ..and the wheel lock up and will slide all the way . with abs , it will slide but u still can control it .
so ,abs is a great thing too . during wet , it is important . during dry , don't think so .
 
TypicalGuy said:
ABS only prevent..but cannot shorten the stopping distance...

if u refer to friction coefficience vs tyre rotation speed graph, max braking force happens just before the tyres lock up.
so, if u compare with a lock up car (which is skidding), an ABS car of course has a shorter stopping distance....as long as the driver press the brake pedal hard enough, and dun release it. because the abs has a kick back feeling on ur foot.
 
jigc said:
if u refer to friction coefficience vs tyre rotation speed graph, max braking force happens just before the tyres lock up.
so, if u compare with a lock up car (which is skidding), an ABS car of course has a shorter stopping distance....as long as the driver press the brake pedal hard enough, and dun release it. because the abs has a kick back feeling on ur foot.

a what graph?? never seen or heard it before.
 
jigc said:
if u refer to friction coefficience vs tyre rotation speed graph, max braking force happens just before the tyres lock up.
.

this is what i have been trying to say. thanks
 
jigc said:
if u refer to friction coefficience vs tyre rotation speed graph, max braking force happens just before the tyres lock up.
so, if u compare with a lock up car (which is skidding), an ABS car of course has a shorter stopping distance....as long as the driver press the brake pedal hard enough, and dun release it. because the abs has a kick back feeling on ur foot.

yeah i would like to see the graph also.. just went through my books cannot find the graph.. where can i see it?.. i just seen my lecturer slides.. just talking about the case of non-slipping n the case of slipping..

In the case of non-slipping the friction force = StaticCoefficent(Weight of the object)

In the case of slipping Friction Force = KinecticCoefficent(Weight of the object)

Kinectic Coefficent < Static Coefficent

So i dun know if this is correct... i will try double check with my coursemate.. i think is related to the graph
 
Do you think a driver without ABS have better braking technique or the one with ABS...
I saw a news article from overseas saying that the more these things are put into a car. The driver will be more depended on these things...thus making them have more lousy driving technique..I'm not shooting anyone here... I saw this on astro discovery channel too on the Extreme machines episode. An old guy saying that now drivers are all depended on electronics gadgets...
 
if the driver only know how to tekan the break pedal but duno how to turn the steering, no point having ABS.
 
jigc said:
if u refer to friction coefficience vs tyre rotation speed graph, max braking force happens just before the tyres lock up.
so, if u compare with a lock up car (which is skidding), an ABS car of course has a shorter stopping distance....as long as the driver press the brake pedal hard enough, and dun release it. because the abs has a kick back feeling on ur foot.


old generation abs i dun think can...but new generation sports ABS i believe can....

ABS dun work on ice....
 
i use abs b4,its safe my life..that time i was going down hill at ulu yam,i wan overtake the kembara..the opposite got 2 lane,then got 1 car come it,i thought he didnt mention me n the kembara also accelerate also..then i jam brake then i heard my tyre grip n the abs work,my abs light was shining n my stering keep shaking..i hear the sound duk duk duk continuos then i slow my car n get back the proper lane..
 
Accord, drive safely ah next time....glad you are OK...
 
boggysv said:
With you "human-ABS" you need to release pressure to let that wheel regain traction.
With ABS, just keep your food on the brake pedal and smile, like this>>>:D
:mad:

hahahahaha....:D
 
boggysv said:
For a flat ideal road, where everything is predictable, if a driver does not lock-up his wheels, the car has the same braking characteristics as a similar model without ABS.

If he slams on the pedal, activates the ABS, he might have a slightly longer braking distance, but i doubt it is MUCH longer.

How many of us dare to claim that we are so good to keep the tyre near the limit so consistently? Even in unfavourable conditions?


Lets throw in some variables to the equation.

Lets assume you are speeding down your fav road, doing maximum braking preparing yourself for the corner ahead. Suddenly, you see a makcik in the middle of the lane, directly ahead of you.

Most of the time, drivers will press harder and lock their wheels, and the makcik goes.

If not, you can try to steer, and the resultant weight-shift and direction change will reduce grip on the inner tyres, and you get a lockup inside. You can either choose to release the pedal, waiting for the tyres to regain traction to steer, or you can choose to start tapping of the brakes, hoping for the best.

Or you use your super driving skills and release brake pressure and steer, avoiding the auntie, and since the braking effort is decreased, you couldn't slowdown enough and hence, bond with the wall/divider.

Or, lady luck is on your side, superman comes and saves the auntie and you.

Who is willing to take this risk??

Now, everything can be better with abs. You get to steer away safely, and the auntie survives, all without the help of superman. You do not need to think what to do, just pray and turn the steering to your desired direction.


Now, imagine, one wheel gets into an oil puddle.
With you "human-ABS" you need to release pressure to let that wheel regain traction.
With ABS, just keep your food on the brake pedal and smile, like this>>>:D

Tell me, how high are your chances to correct your situation better and faster compared to a computer?

Therefore, IMHO, in a road car, ABS is one hell of a safety feature, and I wouldn't be surprised if they don't grant permission to sell cars without ABS in other countries soon.

The myth that people have more accidents might be due to the fact that they released the pedal when they felt the pulsing. A lot a people who are not aware of the system would normally react that way.
Older drivers would use back their "human-ABS" and confuse the system.
That's why we NEED to read the instruction manual!!!

Last but not least, if raikonen had abs, he might have won the last GP:mad:

nicely said with some humour too. bottom point is, ABS saves lives and i've lost count the number of times i jam brakes and counter steer to avoid knocking into things. as much as we say we can do "human ABS", i doubt anyone here has the nerves to release brake pressure, steer the steering correctly and continue braking. its simple because we're not trained and prepared during such situations.

we can't compare our daily cars to racing drivers and their machines simply because these guys are trained in various circumstances and know what to do on the track. ABS is not used in racing, for instance in F1 is not because the drivers are pro and good enuff not to use them. but simply because drivers will exploit the full potential of it by braking so late and right thru the corner. speed will increase, more drivers are in risk of crashing at high speed. and yes, if only raikkonen had ABS, he would have won the race. hehehe. hah, if only raikkonen knew to use "human ABS" as advised by our forummers here.
 
Yeah i agree that most of us.... wouldn't have the reflexes to release the brake preasure to unlock the wheels...
 
Can anyone tell me how did ABS came 1st ??
 
ABS (Honda used to call it ALB) is designed to reduce the chances of accident by minimising tyre lock whenever possible. The secret is to reduce the risk instead of preventing at all which is impossible.

in my knowledge it was German cars that started using ABS with help from BOSCH. then Japanese makers came up with their own system. For example 1988 Sentra B13 has this Anti-skid DP valve that works by reducing pressure under sudden brake application. 1st model Mazda MPV 3.0V6 has only rear wheel ABS.

ABS system evolved with time after hours of research and development. From only 2 wheels to 4 wheel ABS. From 2 channel to 3 and latest is 4 channel and 4 sensors. Early generation ABS actuator can be felt working as it creates pulsation at the brake pedal. More recent cars had managed not to pass the sensation to the driver.

The secret to prevent brake locking is to brake and release a few times per second which is definitely impossible to human capabilities. And yes it does shortened the braking distance over slippery surface compare to similar non-ABS car. This had been tested and proven by professionals and car manufacturers all over the world; if it is not so, then I wonder why they still sell cars with ABS?

personally speaking... I prefer cars with ABS - it make me feel more confidence. After all I am not a superhuman that can make dead people back alive. But as of time being I still stick to my car's front ventilated discs/rear drums setup. he he..
 
mjuvsslip.jpg
 
here is the graph with some remarks.
when slip equal to 1, tyre is locked up.
as u can see, max mju (coffiecient of friction) happens at 0.15~0.2 for dry and wet road.
and it decreases toward tyre lock up.
so, abs system works in this range and maintain max mju to reduce braking distance.
 
TitanRev said:
Can anyone tell me how did ABS came 1st ??

http://www.bosch.de/start/content/language2/html/734_2880.htm
http://www.bosch.de/start/media/BOSCH_ABS_Infowand_eng.pdf
 

Similar threads

Posts refresh every 5 minutes




Search

Online now

Enjoying Zerotohundred?

Log-in for an ad-less experience