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Autopilot - Car spacing

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I have had my car for 3 days and it has been great. I noticed on autopilot in stop and go traffic with 2 car distance set, it gets as close as 1 car distance without anyone cutting me off. Is this normal?
I haven’t noticed that. In fact, 1 car distance seems more like 2+ car lengths to me. Still leaves room for people to cut in.
 
Note that Autopilot still is not perfect at estimating the rear bumper distance for every kind of car. This has been getting dramatically better over time, but it can still get fooled by certain kinds of trucks as well as passenger cars with more rounded rear ends.

So sometimes, AP will get really close because either the vision or radar thinks the car is farther away, and then at some point the ultrasonic sensors pick it up and AP backs off.
 
As an aside, the Prius the SC gave me, because they were out of Tesla loaners, has adaptive cruise control, and it seriously blows. Does this thing where, when it stops, in stop and go traffic, it requires you to use the cruise control lever or press the gas to get it going again. And then it seems to lurch forward and slam on the brakes. Awful.
Really? It doesn’t stop and go on it’s own?

Humm per this demo at around 2:30 to 2:45 he says it starts off by itself.


Man. Free TACC on the Prius. But $5000 on the model 3!?
 
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Really? It doesn’t stop and go on it’s own?

Humm per this demo at around 2:30 to 2:45 he says it starts off by itself.


Man. Free TACC on the Prius. But $5000 on the model 3!?
Maybe I’m using it wrong. It starts and stops on its own as long as the stop is momentary, but it seems like when you come to a complete stop for a prolonged time, it goes into some kind of hold mode. Screen says to start again, to use the stalk, or step on the accelerator. Then it does the herky jerky thing when you press the gas.

Also only seems to have 3 levels of car spacing.
 
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Really? It doesn’t stop and go on it’s own?

Humm per this demo at around 2:30 to 2:45 he says it starts off by itself.


Man. Free TACC on the Prius. But $5000 on the model 3!?

I don't know why I wasted 5+ minutes to watch that, but he did't say that it will come to a complete stop and start again. However, at the 5:10 mark, he did say that "Cruise Control will disengage when it encounters the stop."
 
The Toyota Radar Cruise Control system can and does go into pause mode where you need to tell the car to start driving again. You should read the manuals if this is your car to be familiar with its systems. I read/skimmed the manuals (particularly the active safety features) because I occasionally drive my parents’ new Camry.

The Radar Cruise Control on the Camry, and I’m guessing all Toyotas, will go into pause/stop mode if the car is stopped for 3 seconds while the Radar Cruise Control is active. The car will just sit there when the lead car pulls away. To resume, you need to either press the +/RES button on the steering wheel or press the accelerator pedal to get the car to resume tracking the lead car.

I do like that Toyota gives access to a dumb cruise control if the radar version is not available (ice on the sensors, etc...) or by choice when activating the system. Tesla chose to permanently disable the old style cruise control on any car with TACC to avoid confusion of which mode the car is in. I can see either decision as valid, but prefer the one that Toyota made.
 
As an aside, the Prius the SC gave me, because they were out of Tesla loaners, has adaptive cruise control, and it seriously blows. Does this thing where, when it stops, in stop and go traffic, it requires you to use the cruise control lever or press the gas to get it going again. And then it seems to lurch forward and slam on the brakes. Awful.
I have ACC (Adaptive Cruise Control) on my 2012 Prius and have used it for several years. It is much better than dumb CC. ACC can be set for one to three bars following distance. This is NOT car lengths but a distance algorithm based on speed. The ACC shuts off automatically at speeds under 30 mph and/or when brakes are applied and then you need to reset the stock to engage at previous setting. With ACC on, auto braking and auto resume can be a bit abrupt if you are not used too it. The caveat is that this system is on a 6 y.o. old car and newer cars may have an updated system.

Tesla TACC is much more advanced and better than the ACC on my old Prius. If the SvC gives me a Prius as a loaner when my model 3 is in for service, I will have a little discussion with the manager. o_O
 
Teslas used to do something similar. If the car was stopped for more than a few seconds you had to reengage it. IMHO that was a completely ridiculous design. Fortunately Tesla realized it and removed the "feature".

The TACC Hold feature has not been removed, it is still there and will still activate under certain conditions. However, the logic of when it activates has been refined and you'll only see it rarely now.

One situation where Tesla's TACC Hold feature will activate is if a pedestrian walks in front of your car when TACC has stopped behind another car. The reason is that a pedestrian is small enough where he could be still standing in front of your car and the ultrasonic detectors cannot see him. (And since the pedestrian is not made of metal, the radar can't see him either). In that case, the Tesla will show "HOLD" near the speedometer, and will require that you tap the accelerator pedal to continue moving forward. This is so you can visually verify that the pedestrian is clear before you proceed.
 
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Maybe I’m using it wrong. It starts and stops on its own as long as the stop is momentary, but it seems like when you come to a complete stop for a prolonged time, it goes into some kind of hold mode. Screen says to start again, to use the stalk, or step on the accelerator. Then it does the herky jerky thing when you press the gas.

Also only seems to have 3 levels of car spacing.
I've had the Model 3 require me to step on the accelerator after being stopped in traffic on autopilot for a longer period of time.
 
I've had the Model 3 require me to step on the accelerator after being stopped in traffic on autopilot for a longer period of time.
I don't have the manual handy, but I remember the Tesla ACC takeoff timeout is about 5 minutes.

Other than that, pedestrians or ultrasound obstacles can trigger a HOLD warning.

Once I was behind a Toyota Corolla who put dolls with baseball caps on their trunk shelf. Autopilot seemed to think those were pedestrians and it would trigger HOLD every time it stopped. Grumble….
 
I've noticed since the .18 release that autopilot follows a lot further back even on the 1 setting which I pretty much always use. Much better before.
Thanks for confirming that I wasn't just going crazy.

I've been seeing many more vehicles cut in front of me lately when in AutoPilot after that update. I work around it by pressing on the accelerator when I feel like someone is about to cut me off without a turn signal just because. Would be nice if there was a new 0.5 setting or something.
 
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