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jackmott

I have a Tesla, when using just cruise control it has slammed the brakes:

because of shadows that confused it

because of concern about cars crossing the intersection ahead where there is only the need to gently slow

because of a car crossing an intersection ahead that has already crossed!

because of a steep bridge that confused it

we can’t use cruise control in the car basically, we decided it is too dangerous at worst and jarring at least

because there is so much hype around Tesla people get the impression their software is “hardcore” but a lot of it is absolute garbage.

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The worst part of phantom braking is not just the need for a sudden human intervention. It’s that the required human intervention is extremely non-intuitive.

Intuitively when a car suddenly slows down it feels like the right response is to press on the accelerator: however in my experience this puts you in an unstable regime where you are “fighting” with the car. That is, autopilot continues to try to stop but temporarily accepts your override, but only as long as you maintain consistent pressure on the accelerator. Unfortunately if you even briefly let up on the accelerator, the car proceeds to violently slam on the brakes again. This can lead to a feedback loop where the car’s rapid acceleration/deceleration pattern makes it difficult to maintain consistent pressure on the pedal, and so the experience is like being in a rodeo. Worse, there’s no obvious way “out” of this cycle except to take your foot off the accelerator and let the car (briefly) win.

Counterintuitively, the “correct” way to deal with phantom braking is to avoid the accelerator entirely and instead dive right for the brake pedal: this instantly disengages cruise control. But this is not an intuitive response, you have to learn it the hard way.

There's a button on the steering wheel of my Impreza that I can press to turn off the cruise. I press that and then brake or accelerate as needed

It is interesting that in all the talks with my friends that have a Tesla and have tried other driver assist features from other companies. Is that Tesla is only one we are worried about phantom braking aka a false positive and as such we keep the foot near the gas instead of the brakes.

I’ve also developed a reaction to reach for the stalk with my other hand and disable it at the same time so I’m no longer fighting it.

Protip: Apply the accelerator override, then up on the right control stick to disengage automation. It's the way to smoothly transition from autopilot to human control.

(Then learn when/where/why the car thinks it should be behaving that way, drive it past those zones, and re-engage autopilot. Smooth ride!)

> this puts you in an unstable regime where you are “fighting” with the car

This and your following description sound a lot like analyses of the two 737 crashes caused by MCAS.

> Counterintuitively, the “correct” way to deal with phantom braking is to avoid the accelerator entirely and instead dive right for the brake pedal: this instantly disengages cruise control. But this is not an intuitive response, you have to learn it the hard way.

It is absurd that Tesla is allowed to sell cars that have this problem. Why isn't the NTSB (or whoever) insisting this is fixed and/or removing these cars from the road? They're unsafe. (I had a Tesla; glad I don't now)

I don’t think CV is good enough to rely on for self driving features.

My 6 year old car uses radar for adaptive cruise control and has only tried to (arguably) improperly stop or slow when someone crept over the line into the lane I was driving in. I have no issue turning it on and leaving it for hours at a time.

Have a 3 year old Jeep Cherokee Trailhawk, and before that was exact same model but older by 4 years. On any sufficiently long road trip (800 miles+) a minimum of one time, and sometimes more adaptive cruise control will randomly SLAM the brakes and beep wildly during the day, on a freeway going 60+ with literally nothing in front of me but empty road. Was true with the older one as well and I've never been able to figure out why. It's never done anything more than scare me, no close calls with a vehicle behind me or anything but yeah... all these systems have a ways to go.

> because of shadows that confused it > ...

After all, a Tesla is a pretty good substitute for a horse !

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