Autopilot slowing on tight corners

[Jonathantuba]

Today I was using Autopilot on a windy mountain road (in Germany) and was amazed at how my model X knew exactly how much to slow down for each corner and took perfectly (I was ready to take over whenever not comfortable), but only hairpins could it not handle and I had to manually take over.

Does anyone know how this works? Does it use GPS and map data, or has it learned from the speed of previous Tesla around the corners?

Later in the journey in the Czech Republic the car did not seem to know to slow down for corners in an area where it had no internet connectivity - so it must be getting this knowledge over the air.

I found it fascinating. We may want FSD to arrive soon, but in the mean time I marvel at what Autopilot is capable every time I drive - although am not complacent, or over trusting and are always ready to take over.

 

[Pentium2004]

I'm not exactly sure what methods they are using but I'm thinking it's a combination of GPS and an accelerometer. If you noticed it does it both on AP and TACC. Whenever I turned a little tighter around a corner increasing the G-force it would slow down even more that's what is making me think it may have an accelerometer.

 

[Jonathantuba]

The car obviously knows a corner is coming up and usually slows before. If it does not appear to be slowing I take over.

 

[thegruf]

map data i believe.
mostly works well, but occasionally there are curves that are not recognised for limiting speed, and that's when you need to remember it is Level 2 assistance as it happily barrels into a 40mph curve at 60!

 

[Jonathantuba]

Exactly, the danger is becoming over confident in Autopilot. For example on my journey it could not handle hairpins - there seems to be a limit to how tight corner Autopilot can handle. The thing is to enjoy its use, but be aware of its limitations and ready to always manually take over. The people that have become over reliant on Autopilot, are the ones that have have come to grief.

 

[mattack4000]

A turn that worked in 32, the car almost blew the turn and took out the wall on 39

 

[JMC180]

On a on ramp that went 360 Deg round on itself it gave up the ghost and nearly hit the barrier luckily I was paying attention. Maybe V9 will have sorted these issues?

 

[Nuclear Fusion]

on my journey it could not handle hairpins

Set the speed well under the limit & it will handle it

 

[Peteski]

I believe it's linked to map data. It's not very reliable here in the UK. Slows for some corners reasonably well, totally ignores others or doesn't slow enough. Also brakes approaching certain roundabouts, but not all. It behaves consistently at specific map locations, so I guess it has a speed database linked to the map, but not fully populated. As others have mentioned it also seems to slow as you apply steering lock, so could be using a simple steering algorithm too or possibly an accelerometer.