I agree with thegruf. There are so many other aspects of the car that need immediate improvement, why is Tesla wasting their time on stuff like this. Who at Tesla took it upon themselves to decide that owners should never drive more than 5MPH over the posted speed limit on undivided roads? Let me know, and I'll buy them a custom cap with "Big Brother" on it. I like AP, but if I'm limited to the posted speed +5, I'll have cars stacked up like cord wood where I live.
There's a reason why autonomous driving isn't here yet. Not to even get into regulations but the mere fact that humans still drive like asshats. If you read about Google's self driving cars, they really don't go much faster than 35mph. And there's really no need to speed if proper planning is made before hand. It's not a matter of Tesla taking it upon themselves, it's regulators imposing such limits on autonomous driving risks. Humans at the current moment will more than likely be able to assess a situation and road conditions better than a computer will, so in that case, if AP isn't doing it for you, disable it and drive the car yourself! AP is meant for convenience in ideal driving conditions (highway use, mostly straight roads), not for total reliance in all conditions good, bad, and everything in between.
There are two aspects that I greatly dislike about AP in V7.1.
The first is the +5MPH over limit on undivided roads. Now I don't think this was a bad idea in itself, but the problem is the car doesn't always correctly identify a road or the speed limit. Sometimes it's because of the massively outdated maps and sometimes the MobileEye system flatly reads the speed limits incorrectly. I wouldn't have a problem with if it only impacted engagement. But, my understanding is if it detects that you switched road-types/speed-limits it will slow down and that may have been what happened in the OP's case.
The second is the incorrect lane biasing in the left lane. It's not in the middle, and the car knows it's not in the middle. Instead its shifted to the right. Why???
There is a third element of AP in 7.1 (that may have existed before) is that it excessively slows down for corners. I'm not sure exactly what happened in the OP's case, but in my own experience it slows down before the corner. I suppose with lots of corners that it's slowing in a corner in anticipation of the next corner. Either way I find the slowing to be excessive.
Now that's all arguments against Tesla. To argue in favor of Tesla I'm getting a little sick of people using AP on twisty undivided roads. What are you trying to do? Kill someone???
The car is likely a combination of stored data in maps, as well as reading speed limit signs with the camera over the rear view mirror. As for road types, it's likely reading the lane markings, looking for broken single white lines, double yellow lines, single yellow, etc to determine the road type. I was driving on a local road in CT earlier this week, and found that it restricted my speed to 45mph even though the limit was higher. It sounded like a similar road the OP was driving on, and while I had faith in the AP system, I still appreciated the 45mph limit imposed as if I were personally operating the car faster, it would be in a matter of spirited driving that I wouldn't entrust AP to. It was taking the curves decently at the lower limit, but I still had my hands following the wheel. I think over a period of 20 minutes, I needed to intervene twice slightly to turn the car a little faster/harder. The car didn't make any notifications or chimes to tell me to take control, but I did it on my own out of my own comfort.
Not sure what you mean for the 2nd element of 7.1 AP.
As for the 3rd, that goes to what I said in the first part, the car slowing down to err on the side of caution to not make too sudden of inputs to the car. It is reading the curves in real time, assessing line breaks and such to figure out what to do, while a human already can see the lines at least 1/8-1/4 of a mile down to anticipate how fast or slow you can drive around the corner. Give it some slack
Yes - otherwise Tesla should not permit the AP to be enabled.
Accepting there may be some language differences here, again these were gentle curves on an open road with no obstructions or blind spots, easily taken at 60mph+
The issue at stake is that wherever Tesla get their speed limit data from (clearly not just the road signs) has major errors in it.
So what is posted as a 60mph road, to the Tesla suddenly appears to have no known limit - i have witnessed this many times that the speed limit indicator on the IC just disappears showing no known limit.
This is when the car slows to 45mph (assuming a 40mph liit as it doesnt know any better).
Then when this happens it slows firmly but not sufficiently to illuminate the brake lights.
Now on an dry, open road (and I know you should always be prepared to slow down in reposnse to the vehicle in front) in broad daylight with good visibility you simply dont expect the vehicle in front to lose 20mph in the middle of a gentle curve without warning or indication. Sure the guy behind could have been more attentive and the guy behind him, but this is exactly how accidents happen. Most of the time no big deal, but occcasionally somebody gets caught out.
To take a constructive tone to this situation one thing Tesla could consider is an audible notification to the driver that it has lost speed limit information and is about to default to 45mph. Yes I know - more bongs.
If Tesla were to disable AP on certain roads where line markings were visible, people would be crying afoul about this convenience feature not working as it supposed to - despite still being in beta technically.
As for the curve/blind spot issue and how fast you would normally drive it, keep in mind what I said above - a human can see and account for things that the AP camera may not be able to see as it does in real time as the car passes over it.
The speed limit data I will say needs updating, but that's likely due to the map creators (Google, Navigon, etc). The AP camera confirms it (to the best of its ability). I noticed driving in CT that the AP camera saw a State route sign for Rt 35 and mistook it for the speed limit as I passed it. Granted, they do have similar font and colors, so all I did at that point was disable autosteer and continued to use TACC and steer the car as I knew best.
As for slowing down quickly, how do you know that your brake lights weren't lit up when you were slowing down? I did notice that the car did slow down a bit to 45mph when the message "Autosteer is restricted on this road" came up, but not so drastically to cause alarm to me or to drivers behind me I think. It wasn't enough to affect the balance or handling of the vehicle. Not sure if the brake lights came on or not but it wasn't as strong as a full lift off the accelerator that would invoke regen braking.
So yes, there is a notification to the driver when you invoke AP on a restricted road - there's a different chime. I don't think there is a chime though when AP is active already and you come across onto a restricted road, it just comes up w/the popup. I wonder if those chimes would become annoying. You should still be paying attention to the road and what the car is saying/displaying anyway, if you need a chime to let you know that the road may be curvy and you may need to slow down, you're probably not paying enough attention while driving.
As for the drivers behind, they likely were following too closely as well.
