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Getting TACC to follow the speed limit

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Is there a way to get TACC to automatically adjust speed according to the speed limit? I just got the car, and a hash mark will appear around the speedo that matches the speed limit, but the cruise control does not auto set to that speed. I have to pull and hold the cruise control stalk to set it to that speed, which is a bummer if the speed limit suddenly drops.
 
Is there a way to get TACC to automatically adjust speed according to the speed limit? I just got the car, and a hash mark will appear around the speedo that matches the speed limit, but the cruise control does not auto set to that speed. I have to pull and hold the cruise control stalk to set it to that speed, which is a bummer if the speed limit suddenly drops.

It's supposedly coming, likely in the next update. They demoed this back at the D reveal event.
 
Interesting idea to auto adjust. BUT, I have seen cases where the speed limit sign is misread (truck speed, or school zone when not in session)... if it automatically adjusted, it might cause problems for the cars behind you.
 
Interesting idea to auto adjust. BUT, I have seen cases where the speed limit sign is misread (truck speed, or school zone when not in session)... if it automatically adjusted, it might cause problems for the cars behind you.

Not just an idea - this was a promised piece of the Autopilot package, and was demonstrated in the reveal event last October. I'm sure it is coming... sometime...
 
I hope nobody is using TACC in a school zone!

One place I routinely see problems is on a highway near my house with express lanes. The normal part of the highway is limited to 55, and the express lanes are divided by plastic poles and have a limit of 65. The car doesn't realize that the signs on the left side only apply to the left two lanes, and the signs on the right side only apply to the right four lanes, so it tends to wobble back and forth between 55 and 65.
 
Interesting idea to auto adjust. BUT, I have seen cases where the speed limit sign is misread (truck speed, or school zone when not in session)... if it automatically adjusted, it might cause problems for the cars behind you.

Real world example is I-80 westbound passing SLC International airport. Speed limit is 70 in that area but there is a frontage road that runs parallel to the freeway. Speed on the frontage road is 50. Every time I drive by there on I-80 my car reads the 50 sign for the frontage road and the indicator on the dash quickly drops from 70 to 50.

I've joked with some folks that once the new system is operational someone could construct a sign reading "10" that looks like the real thing. They'd then put that next to the freeway and wait for a Tesla to drive by... :)
 
One would really hope for two things when auto-adjust comes to light:
1 - when adjusting speed, do so somewhat gradually. TACC can sometimes be harsh in adjusting to cars moving into/out of your lane and speed adjustments should be calmer than that
2 - hopefully the car will only auto-adjust up to 15 mph at a time. Any greater change and hopefully it with prompt the driver for input
3 - yeah, a # 3! Hopefully there will be an option NOT to auto-adjust, for the I-80 and Fairfax, VA people.
 
Just as TACC has improved, I'm sure the speed limit recognition will be improved as well before it comes to our cars...and from what I've heard the camera can distinguish between regular speed limit signs and school zone signs...so that should be handled as well.

But as with anything else, you will need to monitor and adjust as necessary.
 
Real world example is I-80 westbound passing SLC International airport. Speed limit is 70 in that area but there is a frontage road that runs parallel to the freeway. Speed on the frontage road is 50. Every time I drive by there on I-80 my car reads the 50 sign for the frontage road and the indicator on the dash quickly drops from 70 to 50.

I've joked with some folks that once the new system is operational someone could construct a sign reading "10" that looks like the real thing. They'd then put that next to the freeway and wait for a Tesla to drive by... :)

Maybe cross reference the signs with GPS data resolves this issue?