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Out-braking the ABS myth [video]

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Re: Out-braking the ABS myth [video]

#11

Post by chris_st »

Temporary_31337 wrote: post #2

The video correctly explains that ABS isn’t about shortest braking distance but more about a predictable trajectory and ability to avoid obstacles where possible. It also takes a lot of guesswork from braking as you can simply instinctively slam the brakes and get good enough results. Especially on a motorcycle slamming the brakes in panic without abs ends up in a crash.

Two experiences of mine: Braking on snowy/icy streets.

First, in a car without ABS, I put on the brakes (I was probably going a little too fast) to avoid hitting the car stopped ahead of me. I started to slow down, but also to slip to the right towards the curb; it was scary, and I barely slowed down in time to avoid either collision.

Second, in a car with ABS, I slowed down to turn into a parking lot, and the ABS kicked in; the car went absolutely straight (without slowing down enough to make the turn), but I wasn't sliding at all, so I didn't have to worry about sliding into the curb. Big win.

Re: Out-braking the ABS myth [video]

#12

Post by justin66 »

briffle wrote: post #8
buildbot wrote: post #6

NB: this video is about motorcycles which have different dynamics than cars. I still think the point holds that in panic situation, it’s better to keep the reactions required simple as possible. Tangential query - is the difference between ABS and no ABS greater or lesser than bad tires and top of the line summers? Getting very expensive tires has quite a huge impact on stopping distance from what I’ve experienced. H…

Family Member is head of training for very large fire department. For testing their truck drivers, if they ABS kicks in at all, you fail the test. They want you to go all the way up to the limit, and ease off the breaks slightly as the 60,000lb truck gets close to kicking in its ABS.

Is ABS a feature on their training truck that doesn't exist on the real rigs, or something?

I've read about police receiving the opposite instruction: a reminder during training that they should keep their foot on the brake when they feel the ABS coming on. Apparently too many police were crashing because they'd lift, and attempt threshold braking as they'd been trained back in the day, when they felt the ABS coming on. They were interpreting the feel of ABS as a loss in traction.

Re: Out-braking the ABS myth [video]

#13

Post by JohnBooty »

j-a-a-p wrote: post #4

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back c…

I got really good at pumping the brakes (is that "dosed braking"? new term to me) in the days before ABS.

You can definitely get close to the performance of ABS with practice. Used to practice in the snow, in empty parking lots. (ABS or no ABS, everybody should safely practice recovering from spins and slides in empty parking lots! It's also really fun...)

The idea that a pro could outperform ABS is surprising to hear. I guess one area where a pro could outperform ABS is if you are trying to slow, not stop. All the ABS systems I've used seem to assume you're trying for a full stop.

Anyway, I'm really glad we have ABS now.

Re: Out-braking the ABS myth [video]

#14

Post by buildbot »

briffle wrote: post #8
buildbot wrote: post #6

NB: this video is about motorcycles which have different dynamics than cars. I still think the point holds that in panic situation, it’s better to keep the reactions required simple as possible. Tangential query - is the difference between ABS and no ABS greater or lesser than bad tires and top of the line summers? Getting very expensive tires has quite a huge impact on stopping distance from what I’ve experienced. H…

Family Member is head of training for very large fire department. For testing their truck drivers, if they ABS kicks in at all, you fail the test. They want you to go all the way up to the limit, and ease off the breaks slightly as the 60,000lb truck gets close to kicking in its ABS.

Well that makes some sense for training professional drivers, which most people are not.

Re: Out-braking the ABS myth [video]

#15

Post by 97-109-107 »

j-a-a-p wrote: post #4

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back c…

I found a lot of humor in your anecdote that the light sensor had to be replaced.

In a similar vein, a family member had a hardware issue in their laptop where some keys would not register some of the time (moisture). Their understanding was that they did not press hard enough for the device to register the press. This confusion between the boundaries of electronic and mechanical problems led to some mocking.

If your anecdote can be taken at face value - they could find some respite in the fact that by pressing the keys too hard they could damage some peripheral electronic parts.

Re: Out-braking the ABS myth [video]

#17

Post by doubled112 »

thnswede wrote: post #7

IIRC this is part of the driving test theoretical portion in Sweden, and then a mandatory "experience the ABS/non-ABS braking". Not much of a myth, there. Spoiler: without ABS, you'll just spin into the moose. With ABS you maybe wont stop, but the main thing is not being crushed by the moose. Not joking about the moose. They put up cones and say this is the moose. Without ABS everyone spins like a carnival ride, and…

This is quite literally called "the moose test" is it not?

Re: Out-braking the ABS myth [video]

#18

Post by briffle »

justin66 wrote: post #12
briffle wrote: post #8

Earlier quoted context omitted.

Family Member is head of training for very large fire department. For testing their truck drivers, if they ABS kicks in at all, you fail the test. They want you to go all the way up to the limit, and ease off the breaks slightly as the 60,000lb truck gets close to kicking in its ABS.

Is ABS a feature on their training truck that doesn't exist on the real rigs, or something? I've read about police receiving the opposite instruction: a reminder during training that they should keep their foot on the brake when they feel the ABS coming on. Apparently too many police were crashing because they'd lift, and attempt threshold braking as they'd been trained back in the day, when they felt the ABS coming…

All modern fire trucks have ABS.

The ABS does allow better control if you break traction, but lenthens your stopping distance. They want their drivers to not break traction, and keep the stopping distance short. Big difference between a Subaru slamming into you because it couldn't stop fast enough, and a firetruck loaded with 1500 gallons of water, etc, slamming into you.

Re: Out-braking the ABS myth [video]

#19

Post by tass »

j-a-a-p wrote: post #4

I did a anti-slip course where we learned dosed breaking to reduce break distance. And once a circuit racing course where the instructor just told me to break with all force available. The latter stuck. This instructor logic was, only if you are a pro driver you actually can outperform ABS. In emergency situations I break with full force without hesitation. This has lead to multiple avoided crashes and TBH two back c…

In a modern (In the past, this was likely true when ABS systems weren't able to control individual wheels. They can do that today, can check for wheel lock-ups and react dozens of times a second, and can therefore compensate for changing grip at different parts of the road during the entire stopping process.

In formula 1, where ABS has been banned, drivers have the capability to manually adjust brake balance (front/back and left/right) which they can do for each corner - so in this scenario it is true but only because they are given an advanced control, practice it over and over for the specific corner, and aren't allowed to use ABS to begin with.

Re: Out-braking the ABS myth [video]

#20

Post by [deleted] »

taeric wrote: post #5

Ok, this entire premise is silly. "Humans can do things that a computer can't" is fine and all, but the entire point is that most people are not practicing that style of braking and can't do it. Heck, the beginning is that most people aren't braking at all during a wreck. Thinking that "perfect braking" would be the answer feels very disingenuous. And if you aren't covering how much speed was lost at the end of the s…

[deleted]
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