Auto Pilot Does Not Like Railroad Crossings!

[rweggert]

Auto Pilot Does Not Like Railroad Crossings
Submitted by rweggert on October 5, 2018
While driving north on a quiet 4 lane country road with Auto Pilot and Auto Steer set at 45mph, I approached a railroad crossing and was curious how the car would respond. The crossing was a double track, fully marked with working gates, etc. The crossing crossed the road at a near 45 degree angle. The roads were well lit and properly lined. As my 2018 Model S100 came within about 20 feet of the tracks, the Take Control alert flashed and sounded. Before I could react, the car turned violently to the left and into the oncoming traffic lanes. I re-gained control and steered back into my lane without further incident. Had any traffic been approaching from the opposite direction, I would have been responsible for a very serious and possibly deadly accident. And if the car decided to turn aggressively to the right instead, I would have either totaled the car on the steel crossing gate posts or driven onto the tracks and into a ravine.

Because I had virtually no time to respond, I don't feel like re-creating the incident to determine what caused the car to react this way. This road was no different than any other highway or expressway so the argument for not engaging driver assist features is not really valid since many highways have rail crossings, cattle crossings, steel bridge dividers, etc.

Has anyone else had a similar experience? Any thoughts on what happened? This experience makes me reluctant to use AP since, even though I was paying very close attention, the car reacted negatively before I could take control.

 

[Jhelin]

I'm guessing the car confused the rails with lane markings and tried to follow that.

Did you have both hands on the wheel? Autosteer has tried to do stupid stuff for me a couple of times but i've had no trouble correcting the steering immediately to keep the car in the lane.

 

[animorph]

That's definitely where hands on the wheel comes in handy. I have had no problem catching my car suddenly swerving unexpectedly, and it has done that. You can react faster if you feel the wheel turning than if you are relying on visual cues. Plus, you already have at least one hand on the wheel ready to counter the swerve, another time saver. Then it's much more survivable. Especially if you're "curious how the car will respond". It would be nice if the car didn't swerve but just went straight when it got confused.

I would have been curious as well. And that's a good indicator to have your hands on the wheel. But any intersection is a possible problem, RR crossings included. The lane lines can be interrupted, and who knows what AP will make of extra lines (or rails) in the intersection.

 

[Electroman]

Rail crossing across a highway?

 

[rweggert]

Yes, a highway is not the same as an expressway. Most highways have railroad crossings, at least in Illinois. I drove the same route today and Jhelin might be correct. As I approached the tracks, my car followed the painted diagonal lines in front of the tracks into oncoming traffic. Since I was driving 45mph, I wasn't able to react quite fast enough before entering oncoming traffic. I suppose a case can be made for no longer using AP when driving on highways either and limiting it to only major expressways or tollways.

 

[dark cloud]

Ditto for me. There is a local road that almost runs parallel to a set of tracks, so what the engineers do is have the road turn hard just before crossing the tracks, then turn back to the original direction after crossing them to increase the angle between the road and the tracks to make it safer for motorcycles to cross. The last thing you want to do with a single contact patch the size of your palm is hit a smooth wet piece of steel at 25 degree angle to the direction of travel.

I have never tried AP at this place as it is a twisty area I prefer to drive myself, and I wouldn't expect AP1 to drive it well, but I let it try today and sure enough it did not perform well. I have no problem trying it again for data collection purposes but I will have to make sure the wife is not with me: She doesn't have the stomach for experimental data for the purpose of science

 

[Uncle Paul]

Auto pilot still has trouble with the difficult situations, but makes easy work of the easy stuff.

 

[pilotSteve]

use voice command “bug report”. Then describe briefly what happened. Tesla will get the message and can download location and other info to help them debug.

 

[dark cloud]

use voice command “bug report”. Then describe briefly what happened. Tesla will get the message and can download location and other info to help them debug.

Did. But used "note". Hopefully goes to the same place. If not I'm sure they can forward the call.

 

[Az_Rael]

When I am in situations where I am not sure how AP will react, not only do I have both hands on the wheel, I am also actively bracing against any untoward movement if the car decides to do something weird.

I had it jump half a lane once during a merge nearly clipping the guy in the other lane. Had both hands on the wheel at the time, but the car can be fast when you aren’t expecting it.

 

[Az_Rael]

Did. But used "note". Hopefully goes to the same place. If not I'm sure they can forward the call.

Best bet to get it actually looked at is to call the service phone number soon after making the report. They can flag it specifically that way.

 

[Electroman]

I suppose a case can be made for no longer using AP when driving on highways either and limiting it to only major expressways or tollways.

Dramatize too much? Hyperbole?

How many rail crossings do you have in that route? over a 100? 2000 maybe?

Just one right? Simply take control a few feet before the rail crossing, and then let AP drive after that. This negativity that if it can't drive every inch of your route, then it is not worth using it is silly. After all it is level 2

 

[rweggert]

No need to be such a a**, Electroman. I was simply sharing my experience with other owners so that they can be aware when in the same situation. As it turns out, this problem happens at every railroad crossing that is identified by striped, angular while lines painted in front of the tracks. The lines are intended to instruct cars not to stop too close to the tracks. But the Tesla sees the lines and aggressively turns to follow the lines and that is where the problem occurs. The same aggressive turn happened in front of a fire department where the lines are drawn to indicate to drivers not to stop cars there. My comment about perhaps not using AP on highways is to alert other drivers that there are instances on highways that may cause your car to behave erratically (as opposed to expressways) and to use extreme caution when doing so.

Apology accepted.

 

[Electroman]

I drove 1000 miles and AP could not negotiate 100 feet of that.

So I suppose a case can be made for no longer using AP...

 

[Flashmasterk]

Thanks for the heads up! I am very new to AP so Ill be careful. I cross 2 set of tracks to and from work each day.

 

[OilAndGas]

I go over a rail crossing daily, 35MPH, AP has had no issues at all regardless of vehicles in front or not.