How ABS works

[professor]

ABS means "Anti-lock Braking System" which comes on many newer cars, is helpful on slippery road surfaces, but to me is another gizmo to go wrong.
But then again, I have been driving something since I was a pre-teen.

I tried to copy / post this article but the pic would not copy so here is a link:
http://www.onehotlap.com/2012/01/abs-exp...beach.html

[Alex K]

It sure can go wrong, but just yesterday, driving on snowy roads, it proved to be very useful again. Of course one can attempt to do cadence braking "by hand", but I don't know if I can always pull it off in the heat of the moment...

[Exian]

What an adorable explanation.

[Alex K]

[JuliaL]

ABS means "Anti-lock Braking System" which comes on many newer cars, is helpful on slippery road surfaces, but to me is another gizmo to go wrong.

Then you're really not ready for self driving cars or auto-land-me planes are you?

Cute explanatory picture, but,
Why did the dog with ABS-ON take longer to stop? Was he going faster?

[professor]

Hi Julia,
This was so good, I thought of Natcachan (but didn't want to call her out) and you guys.

Because I work on stuff, I know complexity brings more things to go haywire.

Right.
I don't want self driving cars.
I would rather deal with the nut behind the wheel than the nut inside the black box (or the one who designed it).

Because ABS pulses the brakes on and off, a savvy driver familiar with vehicle action while braking can out stop the ABS. Those pulses lengthen the distance. However, this only goes for drivers very familiar with the process.
ABS prevents lock up when braking.
Lock up is bad because you loose directional stability when you are sliding down the road.
As long as the wheels are turning with the road- you have control over direction.

Farther down on that link, the author suggests practicing panic stops(when no body is behind you!).
An excellent idea to learn the limits of your ability to stop, and in different conditions.
Something I especially did long ago when I rode a motorcycle.

[Jackalope]

Because ABS pulses the brakes on and off, a savvy driver familiar with vehicle action while braking can out stop the ABS. Those pulses lengthen the distance. However, this only goes for drivers very familiar with the process.

Well, I know that the ABS on both of my vehicles only activates when the wheels begin to lock. There's sensors on each rotor to detect instantly when any of the wheels begin to lock and that's when the pulsing begins. Until then, the brakes act just like a non-ABS equipped vehicle.

[JuliaL]

Right.
I don't want self driving cars.
I would rather deal with the nut behind the wheel than the nut inside the black box (or the one who designed it).

You and John Henry, that steel driving man.
http://www.technologyreview.com/news/520...-you-or-i/
You trust elevators, no?
I'd be interested in seeing a side by side test of skilled drivers without ABS vs ABS equipped and maybe not so skilled drivers. Pumping brakes at just the right rate and intensity to maximize braking while maintaining directional control is a job better suited to automation.
Google (and Toyota, Daimler etc) are really motivated to keep self driving cars safe because of the potentially devastating liabilities. Look at what a slightly bad ignition switch has done to GM. They will heavily fund and develop self drivers and delay rollout until they are really ready.

And as far as autoland goes:

The Air Force has lost many more unmanned aerial vehicles than the Army, in part because Army drones have the ability to land themselves, the Pentagon’s outgoing procurement chief said on Monday.

http://www.stripes.com/news/official-air...my-1.90858
My bolding.
It's hard to give control to our machine overlords. But eventually we'll have to.

[fr0d0]

I want google cars. The remaining risk is human piloted vehicles. Get rid of those and accidents would decrease immensely.

Likewise with ABS. It prevents accidents. Who's going to practice pulse braking? No one I know. In that panic situation most folk will plough into you without ABS.

[professor]

Thanks Cthulhu, for your input. I stand corrected.
Racers don't like it, but for most drivers you're right.
I still like the dogs though.