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Next time you drive, come to a complete stop and feel the car as it rocks back on its suspension. This will happen even if you brake quite lightly. You can slow

Next time you drive, come to a complete stop and feel the car as it rocks back on its suspension. This will happen even if you brake quite lightly. You can slowly raise the brake so that you are barely braking right as you stop, which will almost completely eliminate the feeling, but it makes your stop excruciatingly slow. Theoretically, you could also eliminate the rock back at a stop sign by lifting your foot off the brake right as the car stops (before it moves backwards that little bit). The vast majority of drivers who think they are stopping completely actually lift their foot off right before that moment, so they don't experience the jerk.

Piskvorrr 9y ago
I understand what you mean. "Rocks back and forth" is IMHO a far gentler sensation than "a jerk".
scrumper 9y ago
> lifting your foot off the brake right as the car stops You can do that even if you're braking very hard, and it doesn't have to make your stop slow. All you want to avoid is that bounce back right at the end, and backing off the pressure a bit just before the full stop will be enough to achieve that and create a very smooth ride. Of course you will always have the deceleration but for passengers that's far less jarring than the bounce that happens when the front suspension unloads when the car has stopped. Fortunately it's easy to practice as stop signs are everywhere.
- Retric 9y ago
  Exactly, it took a while to notice this was even possible. It does take a few more inches to stop. But, now I can't help but notice that some people get a lot more jerk
  - Piskvorrr 9y ago
    It's sort of an art, what with variable conditions and whatnot. Surprisingly, automatic trains manage to get it right, being programmed to ease on the brakes just right to avoid a jostle altogether. Fewer variables to keep track of, I suppose.
    - scrumper 9y ago
      Yes exactly, much less going on. It's probably easier with an automatic system than a human brain too. A fairly simple feedback loop between an accelerometer and something to modulate brake pressure should create a pretty smooth stop without much difficulty.

Piskvorrr 9y ago

I understand what you mean. "Rocks back and forth" is IMHO a far gentler sensation than "a jerk".

scrumper 9y ago

> lifting your foot off the brake right as the car stops You can do that even if you're braking very hard, and it doesn't have to make your stop slow. All you want to avoid is that bounce back right at the end, and backing off the pressure a bit just before the full stop will be enough to achieve that and create a very smooth ride. Of course you will always have the deceleration but for passengers that's far less jarring than the bounce that happens when the front suspension unloads when the car has stopped. Fortunately it's easy to practice as stop signs are everywhere.

Retric 9y ago
Exactly, it took a while to notice this was even possible. It does take a few more inches to stop. But, now I can't help but notice that some people get a lot more jerk
- Piskvorrr 9y ago
  It's sort of an art, what with variable conditions and whatnot. Surprisingly, automatic trains manage to get it right, being programmed to ease on the brakes just right to avoid a jostle altogether. Fewer variables to keep track of, I suppose.
  - scrumper 9y ago
    Yes exactly, much less going on. It's probably easier with an automatic system than a human brain too. A fairly simple feedback loop between an accelerometer and something to modulate brake pressure should create a pretty smooth stop without much difficulty.