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> I think it's important as a driver to hit the brakes as hard as you can even if you don't think you'll be able to avoid collision

It's good to hit the brakes, yes, but the best way to avoid almost all collisions is to steer, not just to brake. Braking combined with steering sharply to the left (since the pedestrian was moving to the right) would have been the best response to this situation.

(Note that, before anti-lock brakes became common, "hit the brakes as hard as you can" was not good advice, precisely because it would lock the wheels and prevent you from steering. In a car with anti-lock brakes, that's not an issue.)



Depending on your speed, that is very bad advice. Sounds like a recipe for losing traction and fish tailing (potentially into other cars or people or even stationary objects).

There is only so much traction afforded by the contact patch on your tires. You can brake, you can turn, you can speed up but I would not recommend doing more than one at a time.


> There is only so much traction afforded by the contact patch on your tires

If you have anti-lock brakes, they are designed and calibrated to know how much to brake to be just short of losing traction. That's what they're for--to allow you to brake and steer at the same time without having to have special training to know exactly how to balance the two.

If you don't have anti-lock brakes (but it's very rare now not to have them in a car of recent manufacture), then it's still possible to brake and steer at the same time, but it's not easy or intuitive to balance the two to maintain control. It can be done, but you basically have to be a professional driver.


You cannot argue against the laws of physics.

It is inadvisable for any non professional driver to attempt to maximum break and also steer away. It is just not safe.


> You cannot argue against the laws of physics.

Sure. Anti-lock brakes work in accordance with the laws of physics.

> It is inadvisable for any non professional driver to attempt to maximum break and also steer away. It is just not safe.

This is true for a vehicle that does not have anti-lock brakes. It is not true for a vehicle that does have anti-lock brakes. As I said before, that is precisely what anti-lock brakes are for: to allow you to just push the brake pedal as hard as you can while also being able to steer (because the anti-lock brakes translate "push the brake pedal as hard as you can" into "don't apply the brakes hard enough for the wheels to lock"). And the reason why anti-lock brakes were invented and put into cars was precisely that you need to both brake and steer to avoid most collisions.


I looked into this further, since I was trained to not steer and brake. I understand anti-lock brakes but it does not answer the question of breaking traction, just stops your wheels from locking up (which does maximize traction vs locked wheels).

The answer to the question is ESC (Electronic Stability Control) which is mandated by law in all US vehicles as pf 2012. ESC controls braking on individual wheels to prevent over/under-steering which was my primary concern about swerving in emergency situations.

This short video is a great illustration, it helped me understand how the system works. Looks like my information about swerving is out of date.

https://youtu.be/L1qt84c2KN0

Previously I only found this study that claims people were not driving or braking properly with ABS resulting in more single car crashes due to over-steering while braking.

http://www.smartmotorist.com/traffic-and-safety-guideline/im...


It seems like neither man nor machine took any steering or braking action -- advisable or not.

I also wonder what is the exact job responsibilities are for the human in the car. (The "test driver?") Would love to see the training materials for this role. Are they there to prevent accidents? Or to take over if the car gets "stuck?" (Or both)

This is all I was able to find. http://money.cnn.com/2018/03/21/technology/uber-test-driver-...




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