5 ms·

I hope you are misremembering. Swerving is most often the wrong choice, and I would be disappointed if Waymo were opting for that. By far the best option is t

I hope you are misremembering. Swerving is most often the wrong choice, and I would be disappointed if Waymo were opting for that. By far the best option is to panic stop. Human or robot, physics is a harsh mistress and swerving is more likely to make you lose control and end up in a much more unforgiving wreck.

worldsayshi 7mo ago
> swerving is more likely to make you lose control Even if you're not a panicky human but a optimally regulated control system?
- rootusrootus 7mo ago
  The optimally regulated system doesn't know the road conditions that well. When the road surface is more slippery, it has the most profound effect on lateral friction, way more than braking.
  - deleted 7mo ago
    [deleted]
  - amluto 7mo ago
    The Waymo driver can measure the speed and the acceleration of the offending car and calculate, within at most tens of ms, its range of likely future trajectories. And it can calculate its own likely trajectories under maximum braking. And it can track exactly where all obstacles are that would matter if it swerves. All at once. And it can execute that emergency lane change with the control input that is least likely to cause a loss of control and most likely to successfully avoid the other car. It even has processing power to spare to keep playing that Spotify ad!
  - BugsJustFindMe 7mo ago
    > The optimally regulated system doesn't know the road conditions that well. I'd like to introduce you to what autonomous cars were already able to do in 2018: https://www.youtube.com/watch?v=khX0UCqcR3M https://www.youtube.com/watch?v=khX0UCqcR3M
taneq 7mo ago
This depends a huge amount on car, driver and situation. It was the right advice for a learner driver in the 90s with no stability control, no experience and no side airbags, because if you’re going to hit something, hitting it front on is the least risky way. I’m not convinced it’s the right advice for a competent driver in a modern vehicle.
- rootusrootus 7mo ago
  It is still standard advice today, as far as I know. Tires are better, stability control is better, but all else being equal you are still much more dynamically stable and have a lot more friction with the road when the car is stopping in a straight line than when swerving. Also, in the case of someone running a stop sign, it is far from a sure bet they are going to hit their brakes at all, so by swerving you increase the odds that you will still hit them, but now it will be while you have exhausted all your adhesion on lateral control. So now instead of a front end collision with all the benefits of airbags and crumple zones, you are at a significant risk of rolling the car or spinning off the road and hitting something immovable with a part of your car lacking crumple zones.
  - madaxe_again 7mo ago
    The common mistake is people swerve and brake, which is a terrible combination - you should accelerate through a sudden manoeuvre, as it maintains control through it, much as you should accelerate through corners in general.
    - jjmarr 7mo ago
      Thanks! Now I know why the Waymo didn't slow down.
    - jeffreygoesto 7mo ago
      Wunibald Kamm begs to differ. For his circle, it doesn't matter if the additional force that causes the friction to be insufficient is forward or backwards on top of the side force. In critical situations either use your friction for lateral xor longitudinal action, never both at the same time. Brake hard, but then sail through the curve. You want that vector to move along the circle and never leave it. As that is very difficult for an untrained driver, better switch hard between both modes.
jjmarr 7mo ago
It wasn't possible to stop at the speed the Waymo was moving at. The Waymo didn't have the stop sign, the other driver did, at a three way intersection. The other driver decided to suddenly enter the intersection, when the Waymo was like 5-10 meters away. This was after having stopped at the stop sign. Either they weren't looking or intentionally trying to cause an accident. Swerving prevented the Waymo from crashing at 40 km/h into the driver's door.
bluGill 7mo ago
Most often, but this seems to describe the rare exception.
Fire-Dragon-DoL 7mo ago
I assume waymo has a constant full picture of what's around, so swerve should be way safer for a machine than a human
kcrwfrd_ 7mo ago
For a human this advice is true. But what if a computer can near-instantly calculate a perfect swerve within the performance envelope of the car and driving conditions?
sokoloff 7mo ago
There are many cases where swerving will avoid an accident that braking cannot and cars unexpectedly pulling out from the side are often among these. It’s not a majority, but it’s not at all rare.
bryanlarsen 7mo ago
Anecdotally it does appear that Waymo's do default to braking in many situations where a normal human would choose to swerve.

worldsayshi 7mo ago

> swerving is more likely to make you lose control Even if you're not a panicky human but a optimally regulated control system?

rootusrootus 7mo ago
The optimally regulated system doesn't know the road conditions that well. When the road surface is more slippery, it has the most profound effect on lateral friction, way more than braking.
- deleted 7mo ago
  [deleted]
- amluto 7mo ago
  The Waymo driver can measure the speed and the acceleration of the offending car and calculate, within at most tens of ms, its range of likely future trajectories. And it can calculate its own likely trajectories under maximum braking. And it can track exactly where all obstacles are that would matter if it swerves. All at once. And it can execute that emergency lane change with the control input that is least likely to cause a loss of control and most likely to successfully avoid the other car. It even has processing power to spare to keep playing that Spotify ad!
- BugsJustFindMe 7mo ago
  > The optimally regulated system doesn't know the road conditions that well. I'd like to introduce you to what autonomous cars were already able to do in 2018: https://www.youtube.com/watch?v=khX0UCqcR3M https://www.youtube.com/watch?v=khX0UCqcR3M

taneq 7mo ago

This depends a huge amount on car, driver and situation. It was the right advice for a learner driver in the 90s with no stability control, no experience and no side airbags, because if you’re going to hit something, hitting it front on is the least risky way. I’m not convinced it’s the right advice for a competent driver in a modern vehicle.

rootusrootus 7mo ago
It is still standard advice today, as far as I know. Tires are better, stability control is better, but all else being equal you are still much more dynamically stable and have a lot more friction with the road when the car is stopping in a straight line than when swerving. Also, in the case of someone running a stop sign, it is far from a sure bet they are going to hit their brakes at all, so by swerving you increase the odds that you will still hit them, but now it will be while you have exhausted all your adhesion on lateral control. So now instead of a front end collision with all the benefits of airbags and crumple zones, you are at a significant risk of rolling the car or spinning off the road and hitting something immovable with a part of your car lacking crumple zones.
- madaxe_again 7mo ago
  The common mistake is people swerve and brake, which is a terrible combination - you should accelerate through a sudden manoeuvre, as it maintains control through it, much as you should accelerate through corners in general.
  - jjmarr 7mo ago
    Thanks! Now I know why the Waymo didn't slow down.
  - jeffreygoesto 7mo ago
    Wunibald Kamm begs to differ. For his circle, it doesn't matter if the additional force that causes the friction to be insufficient is forward or backwards on top of the side force. In critical situations either use your friction for lateral xor longitudinal action, never both at the same time. Brake hard, but then sail through the curve. You want that vector to move along the circle and never leave it. As that is very difficult for an untrained driver, better switch hard between both modes.

jjmarr 7mo ago

It wasn't possible to stop at the speed the Waymo was moving at. The Waymo didn't have the stop sign, the other driver did, at a three way intersection. The other driver decided to suddenly enter the intersection, when the Waymo was like 5-10 meters away. This was after having stopped at the stop sign. Either they weren't looking or intentionally trying to cause an accident. Swerving prevented the Waymo from crashing at 40 km/h into the driver's door.

bluGill 7mo ago

Most often, but this seems to describe the rare exception.

Fire-Dragon-DoL 7mo ago

I assume waymo has a constant full picture of what's around, so swerve should be way safer for a machine than a human

kcrwfrd_ 7mo ago

For a human this advice is true. But what if a computer can near-instantly calculate a perfect swerve within the performance envelope of the car and driving conditions?

sokoloff 7mo ago

There are many cases where swerving will avoid an accident that braking cannot and cars unexpectedly pulling out from the side are often among these. It’s not a majority, but it’s not at all rare.

bryanlarsen 7mo ago

Anecdotally it does appear that Waymo's do default to braking in many situations where a normal human would choose to swerve.