LTA problem - Lane Tracing Assist

[ernieb]

I travelled up the M1 today around 9am, low sun from the rear quarter of the car. I had the LTA on travelling at around 62mph (GPS).

The system was functioning OK and then suddenly pulled the car out of my lane into the inside lane. I worked out that the camera system had picked up the old ‘cats eyes’ positions which had been removed and sealed with tarmac. These were about 60cm inside the markings for the running lane and it was exactly where the car tried to position me. The sun was catching the new tarmac and producing a bight very reflective surface. I steamed the car back and the system reposition itself OK.

I’ve noticed the effect visually in the past but this managed to fool the onboard systems completely.  I have the system set to guide the car only if I move out of lane and not to track the lane.

[Cyker]

Yeah you have to keep an eye (or a hand!) on it as it is easily fooled by tar snakes, concrete and tarmac joins, missing or poorly maintained lines, spilt paint, bright or reflective ribbons of road debris etc.

Treat it like it's a learner you're chaperoning  

 

[ernieb]

In the over 3 years I had the Subaru XV which was fully optical for all the safety systems I never had an issue. The RAV often ‘freaks’ at these repaired road features, todays was just dangerous. The M1 is absolutely full of repairs and patches especially where they have been remodelling the 3 lane running to 4 lanes (aka smart motorway)

[Yugguy1970]

Turned it off on mine 5 minutes after I got the car.

[Rav Rob]

I use it massively daily with lane keeping on, and only really have issues passing some exits when it can pull towards the exit sometimes, or a wet road in low sun when its very hard to see anything.

But I am usually also following other vehicles with a radar cruise locked on. In this situation the system when it loses a good lock on road lines, is supposed to use the radar on the vehicle ahead to maintain the steering trajectory. Maybe that is why I get very, very little unexpected incidents as it copes better like this.

I am also always aware of my windscreen, if my view is impaired, so is the cars camera looking through it and there is a lot of salt and spray around now, it must degrade the image and make it harder for the software to resolve a good track, worth keeping it as clean as possible with a regular washer squirt.

[Bernard Foy]

I find LTA practically useless and dangerous if you were not accustomed to it around our narrow hilly roads and streets and I sometimes turn it off as soon as I take off. Unfortunately it automatically comes on again when starting a new journey. It probably will work ok on the motorways.

[Hayzee]

9 hours ago, Yugguy1970 said:

Turned it off on mine 5 minutes after I got the car.

Can it be turned off permanently? 

[Stopeter44]

6 hours ago, Bernard Foy said:

I find LTA practically useless and dangerous if you were not accustomed to it around our narrow hilly roads and streets and I sometimes turn it off as soon as I take off

I’ve grown to like it. In the beginning the beeping really annoyed me, I switched the warning from beeps to steering wheel vibration. Since nothing untoward has happened, it corrects minor lapses of attention, such as when distracted from the road ahead when the road is not straight.

With ACC it helps reduce driving fatigue on the autoroute.

[Stopeter44]

1 hour ago, Hayzee said:

Can it be turned off permanently? 

It depends on the model. You’ll need to check the manual, not possible on the Yaris IV to permanently switch off.

[ernieb]

I have my LTA set to nudge the car back into the lane rather try to steer along the centre of the lane. I found that the later hunted and had a bias towards the left side. I only use it in conjunction with ACC and only on motorways.

[ernieb]

1 hour ago, Hayzee said:

Can it be turned off permanently? 

The '21 PHEV can be turned off and various setting adjusted.

 

[Hayzee]

2 hours ago, ernieb said:

The '21 PHEV can be turned off and various setting adjusted.

 

Thanks Ernie.....If I read the manual correctly, once I disable it, it will still be disabled at next vehicle start-up?

[philip42h]

34 minutes ago, Hayzee said:

Thanks Ernie.....If I read the manual correctly, once I disable it, it will still be disabled at next vehicle start-up?

Yes ...

Irrespective of all the exciting settings there's a button on the steering wheel to activate (according to your selected settings) or deactivate the LTA system. And the car remembers how you've set that button - on or off.

On mine (RAV4) it was set to 'off' when I pick-up the car. I played with it a bit, didn't like it, and switch it 'off' again. I may use it on long motorway journeys or I may not.

On my wife's C-HR it was set to 'on' on delivery. She's got used to it and, I believe, defaults it to 'on' all the time.

It's entirely your choice ... 🙂

[Rav Rob]

Yes I have it set so its default off, no warning beeps crossing lines, no steering interference. Only active when I press the steering wheel button and activate steering assist only, when not needed switch off again. It would be annoying all the time.

[Yugguy1970]

RAV it can be turned off completely, Yaris no.  Has to be turned off every time

 

[Roy124]

Drove today, dual carriage way, usual variation in clarity of lane markings.  It was foggy.  The system didn't have a chance. 

[Cyker]

Yeah it definitely needs some tweaking. It nearly made me clip a badly parked van today as I spotted the out-turned wheel a bit late and turned a bit more to avoid it but the LTA went beeep! and tried to steer me back in to keep on this side of the dashed line!

It's weird as it's the first time it's done this - I often have to cross the central divider line to avoid parked cars and it's never done this before and I assumed the system was smart enough to recognise the parked cars!

 

[Nick72]

On 1/14/2022 at 7:20 AM, ernieb said:

I have my LTA set to nudge the car back into the lane rather try to steer along the centre of the lane. I found that the later hunted and had a bias towards the left side. I only use it in conjunction with ACC and only on motorways.

Mine did that. Too sensitive but I dropped the sensitivity setting a notch and now it is mostly fine. Have you tried different sensitivity settings Ernie?

 

I am always using it with the Adaptive Cruise so whether trajectory is aided by the radar positioning of the car in front as a bias to the EO sensing I don't know. But it would make a lot of sense. As per someone's comments earlier. 

[ernieb]

8 minutes ago, Nick72 said:

Mine did that. Too sensitive but I dropped the sensitivity setting a notch and now it is mostly fine. Have you tried different sensitivity settings Ernie?

 

I am always using it with the Adaptive Cruise so whether trajectory is aided by the radar positioning of the car in front as a bias to the EO sensing I don't know. But it would make a lot of sense. As per someone's comments earlier. 

Nick, it’s set low now it’s been OK up till the other day when the sun and markings just totally fooled the system.

[Nick72]

29 minutes ago, ernieb said:

Nick, it’s set low now it’s been OK up till the other day when the sun and markings just totally fooled the system.

Thanks Ernie. I guess a limitation of one or more of the camera resolution, minimum resolvable contrast, and the convolutional neural network behind it all. Still, Tesla's can also be fooled by these effects but they also use the car in front as a trajectory bias based off the camera. But if there's no car in front then that's a problem. To be honest I have a hard time working out what's going on with the temporary and previous markings for the lanes on the M6 and M5 most days!

 

Might be worth checking what happens with adaptive cruise on as per other poster.

[ernieb]

2 hours ago, Nick72 said:

Thanks Ernie. I guess a limitation of one or more of the camera resolution, minimum resolvable contrast, and the convolutional neural network behind it all. Still, Tesla's can also be fooled by these effects but they also use the car in front as a trajectory bias based off the camera. But if there's no car in front then that's a problem. To be honest I have a hard time working out what's going on with the temporary and previous markings for the lanes on the M6 and M5 most days!

 

Might be worth checking what happens with adaptive cruise on as per other poster.

I agree that some of the markings that have been left are very misleading especially when driving with low sun of night time and a wet surface. I’d have no confidence that I could reply of the cars inbuilt systems to navigate these. The issue I had was the abrupt pull on the steering that seemed to be trying to pull me into the inside lane even when the near side marking was clear. If it’s confused or going to make a massive steering change I’d rather it gave a warning and switched off.

I also noticed today something I think you’ve commented on before, braking at a junction which had a rough loose surface, the system seems to get confused as to whether it’s braking or losing traction, there was the loud ABS wheel locking traction  sound but the braking did not happen until I was nearly over the junction. I was not travelling fast so no problem.

[Roy124]

It a problem where real world clashes with 'every conceivable criteria'.  I once wrote and tested a computer program to deal with complex vector calculations based on geographical positions.  Thoroughly tested and fully debugged. 

I took it airborne and it crashed on the first leg. 

[Yugguy1970]

Ernie I've noticed that too, the tc seems easily triggered by even a small section of rough surfaces.