The car is slamming on the anchors. That isn't defensive driving as you described. It's potentially as dangerous as the incident you are hoping to avoid if you have a tailgater. At the very least, it is downright terrible driving etiquette to just wallop the brakes on "defensively". Nobody does it, why does the car?
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Auto-Pilot - I give up, it's downright lethal
- Thread starter tomorrowman
- Start date
The car is slamming on the anchors. That isn't defensive driving as you described. It's potentially as dangerous as the incident you are hoping to avoid if you have a tailgater. At the very least, it is downright terrible driving etiquette to just wallop the brakes on "defensively". Nobody does it, why does the car?
It's quite a common phenomenon that human drivers, even in emergency situations, do no always press the brake as hard as they can for fear of the unknown. The car probably knows how hard it has to brake in order to create the time/space necessary. Again, humans don't always react well just before a potential crash, hence crashes occurs. If the software has deduced that a crash is possible, it has to apply the brakes quickly to avoid that.
As a side note - I do believe you should be more worried about what's in front than what's behind. Drivers behind should be keeping a safe distance, it is their responsibility to do so. If someone is tailgating me I always slow down. Partly to minimise the risk they've caused me, and partly because people shouldn't be bullied into driving faster, which is often what tailgating- people are trying to do.
JupiterMan
Active Member
In all my experiences of this, the other car in the side junction was stationary, was in their lane and not obstructing my path in any way, yet my Tesla still braked for it.
If the other car is nudging out, then yes, FSD has to interpret what is going on and what to do, and I would rather it was on the cautious side, but this is not my experience with this bug.
Sorry, but you haven't addressed the central point I raised. The car's behaviour in the situation described is far from defensive. Any reasonably competent or advanced driver would never overreact in the way the car is bahaving right now.
Furthermore, you've just highlighted another situation where the car fails to act defensively - if it's being tailgated, why doesn't it back off to compensate?
Drew57
Active ember
These comments about tailgating make a very fair point.
I've had instances in other cars where it's been necessary to pump the brakes rather than slam on when I see a potential incident ahead with someone following too close behind & at least one occasion where I swerved, then braked to avoid a likely rear end collision.
If it happened in a Tesla, I'd rather not take the high ground that 'at least I wasn't liable' when in reality it would be obvious to me that my car caused it and probably to everyone else that I had caused it. With any Tesla we also need to be mindful that regardless of fault, any accident is likely to mean a very long wait for parts and repair, with all the inconvenience that entails.
I've had instances in other cars where it's been necessary to pump the brakes rather than slam on when I see a potential incident ahead with someone following too close behind & at least one occasion where I swerved, then braked to avoid a likely rear end collision.
If it happened in a Tesla, I'd rather not take the high ground that 'at least I wasn't liable' when in reality it would be obvious to me that my car caused it and probably to everyone else that I had caused it. With any Tesla we also need to be mindful that regardless of fault, any accident is likely to mean a very long wait for parts and repair, with all the inconvenience that entails.
Indeed.. but when it was pointed out that FSD was poor at turning left (equivalent of turning right to us) there was entire thread of people saying 'turning left is dangerous and it's unreasonable to expect FSD to do it'. I was left wondering how any of them ever got a license..
It's a very different world over there. Tesla attempting to apply the same software causes lots of issues. TBH they need a development team in each country that uses the software there and designs it for that country.
speedyranger74
Member
In 20k miles, FSD always give a way, doesn't matter if should not. If other car should stop but not, Tesla always will give the way. It's trained to do in this manner, but if I don’t agree I will push the accelerator...
interbear
Active Member
Had my first experience of phantom braking yesterday. I’ve only every used TACC/AP on the motorway. I was on the M4 westbound before Swindon, I had TACC set at 60mph in line with the restricted speed limit on that section of the road. Busy traffic, I was in the middle lane, doing 60mph precisely. Plenty of room in front of me, a VW Transporter behind me, quite close, too close for my liking. Phantom braking struck as I was passing a large truck which was to the left of me in the inside lane. Scary as **** for me and my passenger who had, until then, been very impressed with his first trip in a Tesla. Now, nursing his sore neck, he wouldn’t go near one. No doubt similarly scary for the VW Transporter driver behind me who, while too close, was thankfully alert enough to react and avoid running into the back of me. So, no damage done other my confidence in TACC / AP being diluted significantly. When this happens it is genuinely dangerous in my opinion. I’d be much happier if TACC only used the front cameras/radar to avoid being freaked out by what’s happening in the adjacent lanes. From now on I’ll be poised and ready with my foot over the accelerator pedal whenever I use it (if I use it) which really should not be required to use the system safely.
Exactly. Those that pooh-pooh phantom braking and claim it can be avoided by hovering over the brake pedal haven't experienced a real episode.
Whilst there are charts of braking distance I can't find a chart of braking time but an average car will reduce speed by 15feet per second. I;d guess a full-on emergency brake in a Tesla will outperform that. Average reaction time is towards 1second but assume 20fps slowing and a good reaction of 05 sec and that's a 10foot gap reduction behind before we allow for the driver behind to also react. Essentially anyone within 20 feet of your tail is going to hit you and a slow reflex driver behind needs 40 feet or more depending on his brakes. I no longer use automated systems if a car behind is within 10 car lengths in case the driver has his mind wandering. And if I’m behind a tesla I really keep my distance.
Whilst there are charts of braking distance I can't find a chart of braking time but an average car will reduce speed by 15feet per second. I;d guess a full-on emergency brake in a Tesla will outperform that. Average reaction time is towards 1second but assume 20fps slowing and a good reaction of 05 sec and that's a 10foot gap reduction behind before we allow for the driver behind to also react. Essentially anyone within 20 feet of your tail is going to hit you and a slow reflex driver behind needs 40 feet or more depending on his brakes. I no longer use automated systems if a car behind is within 10 car lengths in case the driver has his mind wandering. And if I’m behind a tesla I really keep my distance.
The legal situation here I think is clear, it is absolutely the responsibility of all drivers to maintain a safe distance from the car in front and modulate their speed accordingly - they cannot know whether an obstacle they can't see appears that forces the car in front to brake suddenly and have to be prepared to slow down or stop safely if that car unexpectedly brakes. Fast forward to the real world and we all experience tailgating and bad drivers with poor attention who may well ram into the back of us if we are forced to brake suddenly, never mind whether Tesla autopilot takes this decision for us or we do it ourselves. Tesla need to fix this bug because we don't want to end up being hit from behind, even if the driver behind is the one at fault.
In the situations this has happened to me, I think I was always driving on a road that curved and the car (once it was a lorry in a lay by) waiting to merge was clearly stationary - I suspect the depth perception of the Tesla system, maybe due to RADAR limitations I don't know, was not accurate enough to be sure the car waiting perpendicular to the road was not poking into my projected path. That is just a guess but if true perhaps better depth perception with the camera system in newer software builds will sort this out.
In the situations this has happened to me, I think I was always driving on a road that curved and the car (once it was a lorry in a lay by) waiting to merge was clearly stationary - I suspect the depth perception of the Tesla system, maybe due to RADAR limitations I don't know, was not accurate enough to be sure the car waiting perpendicular to the road was not poking into my projected path. That is just a guess but if true perhaps better depth perception with the camera system in newer software builds will sort this out.
Theoretically a 3D approach to fsd sorts it - but there'll be a whole slew of new corner cases. I'd take a bet they claim interference between vision and sonar to lose the ultrasonics next.
JupiterMan
Active Member
although we should all remember Phantom Braking, whilst a Tesla issue that definitely needs sorting, is not Tesla specific. my previous car which had TACC and only front camera/radar still had issues, in fact my worse ever phantom brake was in that car, where it actually braked to a full stop for no reason,
I find on motorway sections with narrowed lanes, roadworks with a reduced speed limit, this triggers phantom braking lots. It's a real shame as this is a prime situation to use autopilot, so unfortunately I avoid using it now in situations I know it will trigger.
I don't use AP on A roads but you can't use TACC either, mine does this on TACC all the time in the above situation. It is bloody useless....
I dunno, I think people are expecting too much of it. I also think there's much more chatter about Teslas than any other car, so it makes it look like certain problems are more prevalent than others.
All I can say is a regularly drive Cardiff - Northumberland and back. It's a 700 mile round trip that goes on a mix of motorways and dual carriageways. I use standard AP for most of it and 'phantom' braking occurs maybe 1-4 times per round trip. I've learned what it is that causes it (drifting lorries, sharp shadows, surface spray etc). Being attentive all the time it is engaged (as everyone should be), I can spot these incidents coming, and push the accelerator slightly to override the braking and carry on as before. This is something that's in the instructions and is easy to do.
If there is anything that I think AP may struggle with, something like an unpredictable situation ahead (eg a car trying to cross a dual carriageway), I will disengage AP, until the hazard is passed, then reengage it. I think this is how everyone should be using it. You have to read the road ahead as a driver and think about what may happen. If you do that it is totally fine.
All I can say is a regularly drive Cardiff - Northumberland and back. It's a 700 mile round trip that goes on a mix of motorways and dual carriageways. I use standard AP for most of it and 'phantom' braking occurs maybe 1-4 times per round trip. I've learned what it is that causes it (drifting lorries, sharp shadows, surface spray etc). Being attentive all the time it is engaged (as everyone should be), I can spot these incidents coming, and push the accelerator slightly to override the braking and carry on as before. This is something that's in the instructions and is easy to do.
If there is anything that I think AP may struggle with, something like an unpredictable situation ahead (eg a car trying to cross a dual carriageway), I will disengage AP, until the hazard is passed, then reengage it. I think this is how everyone should be using it. You have to read the road ahead as a driver and think about what may happen. If you do that it is totally fine.
First long drive today with a colleague passenger. Some of the positive experience ruined by phantom braking at numerous points along the M1. At the end I switched it off. Really a shame as the idea is good and the system is definitely a bonus, until it slams on the breaks!!!
With the serious proposition about relaxing the rules for the driver on certain roads with AP engaged, it just has to improve. There is no need to have any sympathy for this issue, it's just a fact it needs improvement and it fails in some situations. Other cars have similar issues, but that is for their forums really.
Be interesting to see how vision only improves things as it gets used globally in varying situations.
Be interesting to see how vision only improves things as it gets used globally in varying situations.
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