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elif 5y ago

By phantom braking, they mean a drop of 10-20 mph to add a safety margin in the potentially hazardous scenario of a car travelling opposed into your lane of travel. It is scary to people because the Tesla makes an unsettling alert noise at the same time the vehicle speed changes slightly. The only way this would result in an accident is with someone else speeding and tailgating. I'll get my tiny violin and 360 dashcam ready for that one.

dataflow 5y ago
> a drop of 10-20 mph > the vehicle speed changes slightly 20mph is not a "slight" change. That's easily a full third of your speed in a freeway (or a quarter if you're speeding), literally the difference between a street and a freeway. And that's easily half your kinetic energy you'd be losing. > The only way this would result in an accident is with someone else speeding and tailgating Surely you can't pretend you've thought of every possible scenario this could turn into an accident? If nothing else, people can momentarily miss the fact that the car in front of them randomly slowed down 20mph, especially when other cars are maintaining their speeds. Doubly so if they're glancing somewhere else to change lanes or watch out for other dangers or whatever. A million things can go wrong that I can't pretend to think of, and I'm shocked you just so confidently ruled them all out. As I see it, just because some of us are mortals, that doesn't excuse letting small mistakes bare our mortality in the middle of a highway.
HWR_14 5y ago
> The only way this would result in an accident is with someone else speeding and tailgating. Let's examine a Tesla traveling at 60 mph starts full on breaking to 40mph, and the person behind them is traveling at (1) the same 60mph and (2) is maintaining the recommended separation for 60 mph and (3) has instant breaking (bonus condition). The driver behind has 2.5 seconds to react to avoid a collision. The average human reaction time for a driver who is expecting breaking soon is 1.5 seconds, but this "phantom breaking"'s deceleration comes out of nowhere. And the average car doesn't have instantaneous speed changes. In fact, an F-150 with similar automatically computer activated breaking would be a coin flip to avoid a collision, certainly a matter of a couple of feet. I've never heard of a better case that even these "safety features" should be disallowed on public roads.