Anyone else find TACC still not trustworthy?

[Three60guy]

Fellow owners:

I am by no means an experienced Tesla owner as I have only had my Model S since the first of July. But even in that short amount of time I can truly relate to others who have noticed the limitations in TACC. Specifically, not always coming to a stop when a vehicle is at a stop ahead of you.

But I would like to add something to this conversation. Maybe a couple of things. First, I have noticed a potential (notice I used that word "potential") relationship of speed versus the ability to stop when a car is stopped ahead of you. Somewhere between 45 and 50 mph and above the car appears to have a much higher statistical chance of NOT slowing to a stop. Likewise, below 40 mph, a higher degree of chance that it will slow to a stop properly.

Second, if I take the first observation and if I am going above 45 mph I have introduced into my driving habits the idea of using the cruise stalk to reduce the speed down to between 35 and 40 mph. Depending on circumstance, I might even go slower. I just click down on the stalk to get to the speed I want to assure I am below the magic numbers 45 to 50mph. At this reduced speed I have found higher confidence in it recognizing the stopped car ahead of me and it will slow to a controlled stop.

I am wondering if anybody else has tried this and what kind of results have you seen? All I am trying to do is help TACC to be able to see a motionless vehicle as there "appears" to be a limitation associated with speed. I am not saying that this should be a work around, just that I have noticed this in my travels.

I am eager to hear back what kind of experiences you guys might have with this info.

Cheers

 

[rhumbliner]

I am afraid I have to dissent here and say that I have encountered a small number of instances in which the car did not slow down when approaching a stopped vehicle. In particular, if the vehicle ahead of you leaves your lane and the next vehicle ahead is stopped, my experience is that the car may not stop in time. This is mentioned as a situation the car may not handle, in the owner's manual. So, vigilance is essential, especially when vehicles change lanes ahead of you...

Ok, I must now agree with @David29. I recently experienced that exact situation in Jacksonville, FL. Traveling about 15 mph, wth TACC set to 35 mph (speed limit) and 2 car lengths, the car in front of me suddenly swerved into the turn lane leaving a stopped car immediately in front of me. Model S accelerated and it was only a quick reaction that prevented a collision.

 

[Saghost]

Ok, I must now agree with @David29. I recently experienced that exact situation in Jacksonville, FL. Traveling about 15 mph, wth TACC set to 35 mph (speed limit) and 2 car lengths, the car in front of me suddenly swerved into the turn lane leaving a stopped car immediately in front of me. Model S accelerated and it was only a quick reaction that prevented a collision.

Firmware 8.0 can't roll out fast enough. I'm always nervous when in AP and approaching stopped traffic, but so far it has always caught it for me. 8.0 should make it much better, and 8.1 will probably be pretty much unshakeable in this regard (on whitelisted roads, anyway.)

 

[Electroman]

Fellow owners:

I am by no means an experienced Tesla owner as I have only had my Model S since the first of July. But even in that short amount of time I can truly relate to others who have noticed the limitations in TACC. Specifically, not always coming to a stop when a vehicle is at a stop ahead of you.

But I would like to add something to this conversation. Maybe a couple of things. First, I have noticed a potential (notice I used that word "potential") relationship of speed versus the ability to stop when a car is stopped ahead of you. Somewhere between 45 and 50 mph and above the car appears to have a much higher statistical chance of NOT slowing to a stop. Likewise, below 40 mph, a higher degree of chance that it will slow to a stop properly.

Second, if I take the first observation and if I am going above 45 mph I have introduced into my driving habits the idea of using the cruise stalk to reduce the speed down to between 35 and 40 mph. Depending on circumstance, I might even go slower. I just click down on the stalk to get to the speed I want to assure I am below the magic numbers 45 to 50mph. At this reduced speed I have found higher confidence in it recognizing the stopped car ahead of me and it will slow to a controlled stop.

I am wondering if anybody else has tried this and what kind of results have you seen? All I am trying to do is help TACC to be able to see a motionless vehicle as there "appears" to be a limitation associated with speed. I am not saying that this should be a work around, just that I have noticed this in my travels.

I am eager to hear back what kind of experiences you guys might have with this info.

Cheers

.

Yes I have observed identical behavior where I am not certain it will Stop all the time to stopped cars when I am cruising above a certain speed limit. So I reduce the speed to less than 50 using the stalk for 5mph reduction for every downward press, just like you had explained.

 

[jdw]

Fellow owners:

I am by no means an experienced Tesla owner as I have only had my Model S since the first of July. But even in that short amount of time I can truly relate to others who have noticed the limitations in TACC. Specifically, not always coming to a stop when a vehicle is at a stop ahead of you.

TACC cannot see a stopped car ahead of you very well, if at all. It can measure speed and distance of a moving object it is tracking.

Radar, as currently implemented, is quite good at tracking a moving object and judging distance and speed. The camera can see a stopped car but can't judge the distance or speed very well. Current TACC/AP depends upon the camera and radar agreeing with each other. No agreement, no stop,

Changes to the radar and decision making in 8.0/8.1 are likely to change this ...in the meantime, do not depend upon the car to stop if it is not tracking a moving car ahead of you. If the car it is tracking changes lanes to avoid an obstruction in the lane, you are quite likely to hit whatever is blocking the lane.