Comment by donatj | Hacker News Reader

Comment by donatj | Hacker News Reader

> Power steering is yet another level of abstraction that further improves the driving experience.

I am a pretty firm believer that antilock brakes are a bad abstraction that might cause fewer accidents, but often more dangerous accidents than they prevent.

They avoid a class of accident caused by the brake’s locking limiting your ability to steer. They cause a whole class of accidents where you hit things at a higher speed than you otherwise would have because your ability to actually slow down is greatly diminished. It’s a trade of braking distance for control. Basically we’re prioritizing rapidly swerving around an obstacle over less controlled but far more rapid deceleration.

I really don’t think this trade off makes any sort of sense in anything but the most sparse rural environment. In urban and suburban areas, swerving blindly around an obstacle will just mean hitting something else. Yes, you missed the car that pulled out in front of you but now you’re either throwing your vehicle into pedestrians on the sidewalk or into oncoming traffic. Both cases likely a far worse outcome than the accident you are taking evasive actions to prevent. The sanest option becomes just to hit the obstacle you would have been able to stop for were it not for antilock brakes.

In my eyes, the most fundamentally frustrating part, and what makes them a bad abstraction, is that the problems antilock brakes solve are entirely preventable by human intervention. Namely, pumping the brakes. The class of accidents antilock brakes cause are largely unavoidable. You can stop lessen their affect by not fully depressing the brake but it is still a much longer deceleration than no antilock brakes at all.

On tarmac you slow down faster with ABS. The friction is higher when the tires are _not_ sliding. Fastest deceleration happens just at the point before tires would start to slide.

On gravel/snow, ABS perfoms worse. But 99% of the time you likely are not in such a context.

Indeed, the friction coefficient is different in case of static (stiction) and sliding contacts: https://en.wikipedia.org/wiki/Friction

I was curious about your statement, so I looked it up:

> ABS increases stopping distances on surfaces covered with gravel, snow, or other loose materials. In such situations, a locked tire digs into the snow or gravel, pushing it forward and forming a wedge in front of the tire, which brings the vehicle to a stop

Source: https://itstillruns.com/do-brakes-work-ice-snow-6162289.html

Unless you live in a place with snow 50% of the year.

Even a racing driver can't beat ABS in a controlled setting.[1] Imagine a regular driver trying to brake in an emergency situation.

[1] https://youtu.be/ERE9EtOWZMU?si=s35N-IzuyPLuEoKD

Do you know that antilock brakes slow down you faster comparing to car with locked wheels?

I think the point was that anti-lock brakes remove options and make things less safe in certain (not very uncommon) instances.

With anti-lock brakes, you're protected if you've never learned anything and you just try to put the brake pedal to the floor.

If you know how brakes work, you're worse off than if you don't have anti-lock brakes, since you can no longer properly control your brakes. In other words, we're punishing people who learn and know how to do things in order to ostensibly protect people who can't be bothered to learn.

Consider how many people drive with their headlights on, but no other lights. It's because automakers are selling "features", so it feels like we're actively encouraging people to think and pay attention less. Unfortunately, these "automatic" lights aren't truly automatic, and the value of having simple off and on states is lost because of these "features". It's actively unsafe.

> With anti-lock brakes, you're protected if you've never learned anything and you just try to put the brake pedal to the floor.

That sounds nice on paper, but in reality you need training in order to overcome the instinct to smash the pedal through the floor... and you need regular practice to avoid reverting to instinct. Needless to say very few people can _actually_ take advantage of manually controlling the brakes.

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