Autopilot can be unreliable on winding roads

[redLamp]

Took a trip yesterday along the North cascade highway. I had set it to autopilot (no navigation since this was a state road). For certain stretches, the car would slow down appropriately on curves. But for many sections, it did not and there times when I had to take over. Some were close calls and it might have just been my anxiety. But there were definitely a few moments where everybody in the car agreed it was dangerous. I eventually took over. It's sad because there wasn't any traffic - the probably was only because of hairpin turns and loops. I would have thought Tesla would have ironed out these kinks.

Anybody else noticed this on their drives?

Model - AWD Tesla model 3 2018, 2021.24.10

 

[Rice&Curry]

Took a trip yesterday along the North cascade highway. I had set it to autopilot (no navigation since this was a state road). For certain stretches, the car would slow down appropriately on curves. But for many sections, it did not and there times when I had to take over. Some were close calls and it might have just been my anxiety. But there were definitely a few moments where everybody in the car agreed it was dangerous. I eventually took over. It's sad because there wasn't any traffic - the probably was only because of hairpin turns and loops. I would have thought Tesla would have ironed out these kinks.

Anybody else noticed this on their drives?

Model - AWD Tesla model 3 2018

It is clearly mentioned in the manual that Auto Pilot may not function appropriately on curving and winding roads and advises not to use AP or FSD in such situations. As a Caution- Tesla has put a full disclaimer on this in the manual so the insurance company will be quick to latch on to it in case of a claim.

 

[Thepugster]

The curve of death.

 

[LionXng]

Took a trip yesterday along the North cascade highway. I had set it to autopilot (no navigation since this was a state road). For certain stretches, the car would slow down appropriately on curves. But for many sections, it did not and there times when I had to take over. Some were close calls and it might have just been my anxiety. But there were definitely a few moments where everybody in the car agreed it was dangerous. I eventually took over. It's sad because there wasn't any traffic - the probably was only because of hairpin turns and loops. I would have thought Tesla would have ironed out these kinks.

Anybody else noticed this on their drives?

Model - AWD Tesla model 3 2018, 2021.24.10

If you are looking for a kink-free driving experience you are going to have to drive yourself. Tesla is working very hard at huge expense to improve and they are leading the world (in my opinion) but you can still get into dangerous situations if you choose to let the car do whatever it wants.

Check out some of their efforts in their AI day video:

 

[Tam]

...For certain stretches, the car would slow down appropriately on curves. But for many sections, it did not...

That has always been the case since I first bought Autopilot in 2017. Autopilot works in some cases and not in others (that's why some drivers are alive and some are dead). I just have to memorize which is which and including memorizing which curves are doable and which are just plain curves of death, even to this very day.

Some people don't like my thinking because that's an excuse for poor engineering. But what else can I do: I can join the living drivers or the dead ones.

 

[KenC]

Took a trip yesterday along the North cascade highway. I had set it to autopilot (no navigation since this was a state road). For certain stretches, the car would slow down appropriately on curves. But for many sections, it did not and there times when I had to take over. Some were close calls and it might have just been my anxiety. But there were definitely a few moments where everybody in the car agreed it was dangerous. I eventually took over. It's sad because there wasn't any traffic - the probably was only because of hairpin turns and loops. I would have thought Tesla would have ironed out these kinks.

Anybody else noticed this on their drives?

Model - AWD Tesla model 3 2018, 2021.24.10

Whether AP can handle a curve depends alot upon your speed, the radius of the curve, and visibility. Interstate highways meet all sorts of engineering standards so that people can drive highway speeds with modest radius curves, and AP has minimal issues. Your State highways don't have to meet those standards. Of course, I'm assuming the speed limits are lower, too, but on sharper radius curves, did you notice whether the speed limits the car is seeing is matching the speed limits on the curve? In general, I found the car can handle the limits posted, but if it doesn't know what those limits are, it's going to have difficulty because it's going to go into those curves at too high a speed.

 

[UncertainTimes]

Curvy roads are the only time I actually want to be driving.

 

[RayK]

Full disclosure: I'm still on 2020.40.8 so some improvement may have been made in Autopilot since then.

Someone here on the forum drove State Highway 17 from San Jose to Santa Cruz on Autopilot about two years ago. It's a four lane divided road (center K rails), which climbs out of Santa Clara Valley, up into the Santa Cruz mountains to a summit of 1800', and down into the town of Santa Cruz on the shores of the Pacific Ocean. Distance is about 35 miles and the speed limit is 50 in the hilly parts. There's a couple of places that have long, sweeping turns and tight radius corners. Personally I would not attempt doing this on AP having driven the road since the early '70s., unless it was done at 45mph. I don't really trust AP to take cloverleaf freeway ramps.

 

[redLamp]

That has always been the case since I first bought Autopilot in 2017. Autopilot works in some cases and not in others (that's why some drivers are alive and some are dead). I just have to memorize which is which and including memorizing which curves are doable and which are just plain curves of death, even to this very day.

Some people don't like my thinking because that's an excuse for poor engineering. But what else can I do: I can join the living drivers or the dead ones.

I do think this is an engineering flaw then. It’d be safer for Tesla to disable AP for streches where system confidence is not high. Or reduce speed on curves to be on the safer side. Otherwise, driver reaction time may not be enough to take over in the middle of AP. Of course, I’m with you in being defensive in driving. But I do want Tesla to hear us out and make improvements (esp because Musk cites safety as the main concern for the AP team)

 

[redLamp]

Whether AP can handle a curve depends alot upon your speed, the radius of the curve, and visibility. Interstate highways meet all sorts of engineering standards so that people can drive highway speeds with modest radius curves, and AP has minimal issues. Your State highways don't have to meet those standards. Of course, I'm assuming the speed limits are lower, too, but on sharper radius curves, did you notice whether the speed limits the car is seeing is matching the speed limits on the curve? In general, I found the car can handle the limits posted, but if it doesn't know what those limits are, it's going to have difficulty because it's going to go into those curves at too high a speed.

There were advisory speed post signs for many of the curves. However, I don’t believe AP follows them (the speed limit on screen remains the same) - this maybe another issue. However, I would expect AP to reduce suitably even if the max limit is higher.

 

[redLamp]

It is clearly mentioned in the manual that Auto Pilot may not function appropriately on curving and winding roads and advises not to use AP or FSD in such situations. As a Caution- Tesla has put a full disclaimer on this in the manual so the insurance company will be quick to latch on to it in case of a claim.

Ah, I did not know about the disclaimer on the manual. Regardless, narrow and winding are not objective measures. Ideally, Tesla should either disable AP or give a fixed banner warning when it deems it cannot safely drive a stretch (like it does if the camera is obstructed, for eg.)

 

[redLamp]

If you are looking for a kink-free driving experience you are going to have to drive yourself. Tesla is working very hard at huge expense to improve and they are leading the world (in my opinion) but you can still get into dangerous situations if you choose to let the car do whatever it wants.

Check out some of their efforts in their AI day video:

I’m pretty stoked about all they’re planning and have already seen the AI day videos. I even bought the FSD package and can’t wait to try out the beta. However, I do think they can do a better job at communicating to the customer situations where AP is unreliable or should not be used. At greater than 50 mph, even if you are paying attention to the road, there may not be enough reaction time to take over and avoid a crash.

 

[Phlier]

This is all just my opinion…

When using autopilot, I “drive” my car using 110% more attention than when I’m driving it without autopilot. I have my hand on the wheel all the time, and actively follow every movement it makes. I never have to worry about reaction time, as there is never any delay between the moment the AP screws up and the time I take over.

I’m going to use it in this manner until it is not just out of beta, but has been approved as a “Level X” driver assist device.

Again in my opinion, you should treat Autopilot as if its sole purpose is to kill you when you least expect it. Why? Because it will do exactly that.

 

[KenC]

...I do think they can do a better job at communicating to the customer situations where AP is unreliable or should not be used. At greater than 50 mph, even if you are paying attention to the road, there may not be enough reaction time to take over and avoid a crash.

Absolutely. It's like every driver who tries AP, has to learn what the car can and can't handle comfortably. Would be nice if they had videos showing where AP has difficulty, so that people would not have to be beta testers. Everyone re-learning the same lessons.

 

[LoL-Gas]

Absolutely. It's like every driver who tries AP, has to learn what the car can and can't handle comfortably. Would be nice if they had videos showing where AP has difficulty, so that people would not have to be beta testers. Everyone re-learning the same lessons.

Maybe in the videos it can show how to handle the situations and when/how to take control back. 99% of the time it works great but every so often there is a blooper that sneaks through!

 

[Stavinski]

It’s terrible at curvy roads, I can vouch for that. Have not tried it with 2021.24.11 yet, just got it yesterday.

 

[dgatwood]

Full disclosure: I'm still on 2020.40.8 so some improvement may have been made in Autopilot since then.

Someone here on the forum drove State Highway 17 from San Jose to Santa Cruz on Autopilot about two years ago. It's a four lane divided road (center K rails), which climbs out of Santa Clara Valley, up into the Santa Cruz mountains to a summit of 1800', and down into the town of Santa Cruz on the shores of the Pacific Ocean. Distance is about 35 miles and the speed limit is 50 in the hilly parts. There's a couple of places that have long, sweeping turns and tight radius corners. Personally I would not attempt doing this on AP having driven the road since the early '70s., unless it was done at 45mph. I don't really trust AP to take cloverleaf freeway ramps.

I was driving SR 17 on autopilot up to four times a week for years. When it isn't under construction, there are only a couple of spots that it does weird stuff, and I'm 99% sure that it wouldn't actually crash except perhaps at that one spot down near the reservoir where it sometimes aims for the gore point of the center barrier at a long gap.

What it absolutely cannot handle is SR 152.

 

[Rice&Curry]

I was driving SR 17 on autopilot up to four times a week for years. When it isn't under construction, there are only a couple of spots that it does weird stuff, and I'm 99% sure that it wouldn't actually crash except perhaps at that one spot down near the reservoir where it sometimes aims for the gore point of the center barrier at a long gap.

What it absolutely cannot handle is SR 152.

SR 152 East towards Watsonville or West towards Pacheco Pass/ Los Banos?

 

[dgatwood]

SR 152 East towards Watsonville or West towards Pacheco Pass/ Los Banos?

Watsonville to Gilroy. I've never been farther east than that.

It has a tendency to cross the centerline. Frequently.

 

[Rice&Curry]

Thanks, good to know - forewarned is forearmed.