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8.0 (2.50.185) caution using TACC/Autosteer features

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MXWing

Well-Known Member
Oct 13, 2016
7,749
24,194
USA
After approximately 8 hours and 100 miles of driving, camera calibration completed on my AP2 which allowed me to activate the limited feature set that was released for 8.0 2.50.185 on AP2 hardware.

I enabled auto steer, and early collision avoidance assist.

I was doing cruise control at 65mph and had 3 occasions where a "phantom red car" jumped in front of my dashboard which immediately causes the model x to slow down.

Each time I turned off cruise control by hitting the brakes to take back full control. This is very problematic as randomly hard breaking for no reason poses a danger to cars behind me who would not see that behavior coming.

Second issue I have found is that adaptive cruise control at the default setting (2) tails a car far too closely. I am estimating it is only 1.5 seconds to hit the car in front of me. I would consider this extreme tailgating.

I will likely turn off collision detection for now and increase the following distance and then cautiously monitor the results for following distances and general "sense of safety".
 
After approximately 8 hours and 100 miles of driving, camera calibration completed on my AP2 which allowed me to activate the limited feature set that was released for 8.0 2.50.185 on AP2 hardware.

I enabled auto steer, and early collision avoidance assist.

I was doing cruise control at 65mph and had 3 occasions where a "phantom red car" jumped in front of my dashboard which immediately causes the model x to slow down.

Each time I turned off cruise control by hitting the brakes to take back full control. This is very problematic as randomly hard breaking for no reason poses a danger to cars behind me who would not see that behavior coming.

Second issue I have found is that adaptive cruise control at the default setting (2) tails a car far too closely. I am estimating it is only 1.5 seconds to hit the car in front of me. I would consider this extreme tailgating.

I will likely turn off collision detection for now and increase the following distance and then cautiously monitor the results for following distances and general "sense of safety".
After approximately 8 hours and 100 miles of driving, camera calibration completed on my AP2 which allowed me to activate the limited feature set that was released for 8.0 2.50.185 on AP2 hardware.

I enabled auto steer, and early collision avoidance assist.

I was doing cruise control at 65mph and had 3 occasions where a "phantom red car" jumped in front of my dashboard which immediately causes the model x to slow down.

Each time I turned off cruise control by hitting the brakes to take back full control. This is very problematic as randomly hard breaking for no reason poses a danger to cars behind me who would not see that behavior coming.

Second issue I have found is that adaptive cruise control at the default setting (2) tails a car far too closely. I am estimating it is only 1.5 seconds to hit the car in front of me. I would consider this extreme tailgating.

I will likely turn off collision detection for now and increase the following distance and then cautiously monitor the results for following distances and general "sense of safety".
i feel the same. But are you sure the auto steer is active at 65mph? Mine can't be activated says has to be below 35mph to be active. I had the same issue like the #1 you mentioned. Mine was more weird there is no cars in front of me instead in the left lane there is a car accelerate fast approaching and the vehicle started to brake strongly. I have to take control and accelerate to avoid tailgating.
 
After approximately 8 hours and 100 miles of driving, camera calibration completed on my AP2 which allowed me to activate the limited feature set that was released for 8.0 2.50.185 on AP2 hardware.

I enabled auto steer, and early collision avoidance assist.

I was doing cruise control at 65mph and had 3 occasions where a "phantom red car" jumped in front of my dashboard which immediately causes the model x to slow down.

Each time I turned off cruise control by hitting the brakes to take back full control. This is very problematic as randomly hard breaking for no reason poses a danger to cars behind me who would not see that behavior coming.

Second issue I have found is that adaptive cruise control at the default setting (2) tails a car far too closely. I am estimating it is only 1.5 seconds to hit the car in front of me. I would consider this extreme tailgating.

I will likely turn off collision detection for now and increase the following distance and then cautiously monitor the results for following distances and general "sense of safety".

2 is not the default setting it's just the setting your vehicle is at. Adjust accordingly based on the driving conditions. I personally stick to 3 unless stop and go traffic
 
Be sure to email Tesla at the email in the release notes to report the bugs.
You can also report quoting date and time right from your Tesla. This is in the owners manual
Screenshot_2017-01-01-19-18-18.jpg
 
Thanks for the report. Be sure to email Tesla at the email in the release notes to report the bugs.

Stay safe while driving with it on :)

Affirmative. I will be sure to let Tesla know ASAP. I really value fellow drivers and share prices of TSLA. Tesla's success is our success so raising the flag early so all issues can be corrected.

i feel the same. But are you sure the auto steer is active at 65mph? Mine can't be activated says has to be below 35mph to be active. I had the same issue like the #1 you mentioned. Mine was more weird there is no cars in front of me instead in the left lane there is a car accelerate fast approaching and the vehicle started to brake strongly. I have to take control and accelerate to avoid tailgating.

Autosteer doesn't activate at 65MPH. It was the collision detection that I am positive of that is causing the sudden breaking. When it breaks, a phantom red car is detected on the console. I am thinking the sensors might be picking up cars above me like on an overpass or something. Will need more testing to confirm.

Well there's a reason it was a limited release. Send info to Tesla so they can fix it.

Yes I agree it was limited. But without being a daily follower of Tesla Motor Club, there's no way that I would of known this. A driver who never reads TMC or reads tweets would know this and might use the features as if they were 100%.

Thanks for testing and having the skill and sense to dodge the early adopter arrows so adroitly. We owe you.

I owe every Roadster and every S owner that made my X possible, and the 1 billion miles driven ahead of me. :) Glad to give back in any way I can.

I don't have an AP2 car, but unless something is radically different, you can regain full control by simply pushing the stalk (the one that you pull to engage TACC and Autosteer) away from you. You don't need to actually brake.

This may be true. However in a crisis situation, muscle memory is to think "BRAKE!" to shut off automation/cruise control.

2 is not the default setting it's just the setting your vehicle is at. Adjust accordingly based on the driving conditions. I personally stick to 3 unless stop and go traffic

I wouldn't call it the default setting. It's just the position in which the knob happened to have. I'm assuming you have the same 7 position knob at the end of the stalk I do.

Update on TACC.

Setting of *7* mimics the closest of how I drive manually at speeds of 70MPH. I have been mostly satisfied with the performance of TACC over 80 miles at cruising speeds of 50-70MPH.

What we really need is ADAPTIVE FOLLOW DISTANCE. Less space at slower speeds and more space at higher speeds. For example, 4-5 seems to work for 50MPH and below. 6-7 is needed for 60-70. Even more than 7 is needed for 75-80.
 
What we really need is ADAPTIVE FOLLOW DISTANCE. Less space at slower speeds and more space at higher speeds. For example, 4-5 seems to work for 50MPH and below. 6-7 is needed for 60-70. Even more than 7 is needed for 75-80.

Not sure how your manual reads, but for AP 1.0 it is said to be a following distance in units of time, so indeed the gap gets wider at higher speeds. Of course, it may simply be that the effect isn't as pronounced as you want. It's amusing because I've heard more complaints in NorCal (home of extreme tailgaters) from folks sitting in my car that even a distance of 2-3 allows other cars in.

I generally use 4 for day to day driving. I find that to be a polite-yet-not-a-doormat distance that allows a looser level of supervision. But when I get stuck in stop-and-go, or get into a backed up offramp and don't want other cars to get in, I'll use 1 or 2 and even occasionally nudge the accelerator to close gaps faster.
 
Pretty crazy how Tesla is using you guys as alpha (not even beta) tester, in real life where speed can go in excess of 70mph. When they completed the validation something like this shouldn't happen. On the bright side it will be fixed eventually, just a matter of when. Good luck.

This shows something I have been saying - will AP2 all of a sudden fix all the issues from AP1 given their track record? Doesn't seem like it and it's starting all over again... beta features, bug fixes, broken features, more bug fixes.
 
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More detailed review on TACC. There are safety issues I also found as well.

Had TACC running for a 90 minute trip across 80 miles in highway and city and had the following observations

1 - TACC works well enough on the highway except for two caveats.
a.) It seems to have a much delayed reaction to vehicles merging/changing lanes in front of it. I was going 70 and had a car "cut" in front of me. TACC did not slow down the vehicle speed as I quickly saw the speedometer never dropped. I had a decision at this point to either brake the car manually or see what would happen next. Since the car cutting in front of me was driving 'slightly' faster than me after merging (bad driver) and had a clear path ahead, I decided to let it ride. I think if a car were to cut in front of me and braked hard, the Model X would have rammed it. Whether the X was in control or I was in control, the rear end result could have happened. The main distinction is if TACC was off, I would of planned in advance for the possibility of that Camry cutting me off and braking before the change lane ever happened. I think what TACC should do is to start breaking the moment a vehicle begins to enter the lane. Vehicles in front of the MX or merging in with plenty of distance, the TACC will adjust the speed as expected.
b.) Following distance is much tighter than what I believe is appropriate for defensive driving. Even if the Model X can react faster than the driver, you are guaranteed to be in for a hard stop. I am not willing to put TACC to the test with no margin of error trusting it will avert rear end collisions - you need more distance for the human to catch issues.

2 - TACC felt very dangerous in the city.

I still had TACC enabled exiting off the highway but dropped the speed limit down to 45 which was the limit of the street. TACC did fine at stopping to 0. As the car in front of me accelerated, the MX went from 0-45 in about 1.5 seconds. Gunning it is NOT COOL when there is a car in front of you that is moving maybe 10-15 MPH. I wasn't sure what TACC was going to do but I only saw two possibilities:
a.) A rear end
b.) A brake hard enough to cause whiplash.

I immediately hit brake to stop the TACC experiment.

I understand these are supposed to be super computers but I've found 3 risky situations already today.

1 - False positives on Collision Avoidance. Phantom cars detected by the MX and breaking in reaction.
2 - TACC having delayed reactions to dangers entering in from the side and not directly in front of it.
3 - TACC inappropriately accelerating when there are objects in front of it going nowhere near as fast.
 
1 - TACC works well enough on the highway except for two caveats.
a.) It seems to have a much delayed reaction to vehicles merging/changing lanes in front of it. I was going 70 and had a car "cut" in front of me. TACC did not slow down the vehicle speed as I quickly saw the speedometer never dropped. I had a decision at this point to either brake the car manually or see what would happen next. Since the car cutting in front of me was driving 'slightly' faster than me after merging (bad driver) and had a clear path ahead, I decided to let it ride.

The earliest iterations of TACC would slow down if a car was changing into your lane, even if that car was moving faster. The fact that TACC can now identify that the car is moving faster, and thus not brake is, in my opinion, a positive and not a negative.


b.) Following distance is much tighter than what I believe is appropriate for defensive driving.

You do know that you can set the following distance, right? The settings are 1 through 7, with 7 allowing for the most distance between you and the car in front of you. What setting were you using?

2 - TACC felt very dangerous in the city.

TACC isn't really supposed to be used in the city. That wasn't what it was designed for.
 
The earliest iterations of TACC would slow down if a car was changing into your lane, even if that car was moving faster. The fact that TACC can now identify that the car is moving faster, and thus not brake is, in my opinion, a positive and not a negative.

You do know that you can set the following distance, right? The settings are 1 through 7, with 7 allowing for the most distance between you and the car in front of you. What setting were you using?

TACC isn't really supposed to be used in the city. That wasn't what it was designed for.

I will have to disagree. What if the car that cuts in front of me with <1 second impact time decides to brake? If it takes dropping 5 mph for 2 seconds to create the necessary separation, that is the action that should be taken. When traffic was stopped, TACC created enough distance for a car that was already in front of it. It should have done the same for cars entering into the lane immediately.

I set my follow distance to 7 - that is close to the space I usually give. However, I don't 'feel' the follow distance is scaling properly at faster speeds.

Yes, I understand that cruise control is not a typical 'use case' for city driving. I thought to test it out anyway so I can do my part to help Tesla make a better product and to inform others to keep them safe. Let me ask you this:

1 - Doesn't AP1 need to use TACC features to function, and wouldn't FSDC need to handle the situation I just described?
2 - Could the city situation I just described happen in bumper to bumper traffic or accident situations when driving on a highway?
 
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MXWing: I wouldn't feel obligated to defend your statements to everyone who questions them. I'm mostly interested in your opinion since you are one of the only people with one of these. Your opinions can't be wrong and they are just as important as the intentions of the developers who wrote the update. If you feel unsafe that seems to be enough of a data point and I'm personally interested in all of your observations. More observations. Ignore the folks who say you are wrong. You can't be wrong.
 
b.) A brake hard enough to cause whiplash.

We're getting a bit hyperbolic here. As someone that has driven some very high performance cars, with some very sticky tires, I can tell you that no car can decelerate quickly enough to cause whiplash, much less a car on street tires.

You're basically saying that every person that has ever braked hard enough in a car to set off the ABS has gotten whiplash.

I appreciate your report on how the software is doing. Blowing the descriptions up so big that they are almost impossible (0-45 in 1.5 seconds?) doesn't do anyone any good.
 
We're getting a bit hyperbolic here. As someone that has driven some very high performance cars, with some very sticky tires, I can tell you that no car can decelerate quickly enough to cause whiplash, much less a car on street tires.

You're basically saying that every person that has ever braked hard enough in a car to set off the ABS has gotten whiplash.

I appreciate your report on how the software is doing. Blowing the descriptions up so big that they are almost impossible (0-45 in 1.5 seconds?) doesn't do anyone any good.

I'll try not to "blow up" descriptions but my point still stands:

It's not appropriate for the car to go 0-45 at maximum speed when the car in front of it is going a 3rd of that at best. Whether it gets to 45 in 1.5 seconds, 1.75 seconds or even 2.0 seconds - a delta of half a second is not a lot of time for a human to react.

A human driver in this situation would give the car in front sufficient space and then also accelerate at a *speed proportionate* to that car as well.

Going 0-45 and then immediately going from 45 to 20 (assuming TACC catches it in time) is not good for the car.
 
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