Hacker News Reader

Comment by colordrops | Hacker News Reader

This is probably happening a lot more than the number of reports mentioned in the article indicates. It happens to me every other day in my Model 3. It's also not binary - sometimes it slows down more quickly than other times, or stops too suddenly when a car is stopped in front of you. Seems real easy to get rear-ended.

I've only got autopilot, not FSD. It's very conservative. It always considers someone to be in front of you even if they've mostly moved out of your lane into the next lane, or they swerve slightly into your lane. I suspect the engineers erred on the side of being rear-ended rather than rear-ending cars in front.

View on HN

You continue using this feature despite these errors occurring daily? The way you describe it makes autopilot seem like an inexperienced teenage driver; I think whatever marginal safety benefit you get from it might be erased by the life-shortening stress such erratic car behavior must induce.

You cannot turn this behavior off persistently -- you need to open car settings and disable it every time you leave Park. My guess is that some jurisdictions mandate this behavior.

When this "feature" triggers you have a short window in which to do _something_ to tell the car that you are paying attention. Your options are either: accellerate or brake. If you do nothing the car may apply full brakes and bring you to a full stop, regardless what is behind you.

> Reports of “phantom braking” first surfaced last fall

This has been happening for much longer than that -- at least as early as Winter 2019, when I unintentionally brake checked a Prius after merging while going over 101 @ Rengstorf.

What behavior are you referring to? We are talking about autopilot, and possibly FSD, neither of which are engaged by default (obviously!) What do you mean they can't be turned off?

> When this "feature" triggers you have a short window in which to do _something_ to tell the car that you are paying attention. Your options are either: accelerate or brake. If you do nothing the car may apply full brakes and bring you to a full stop, regardless what is behind you.

Again, what is this? I have a Tesla, and I'm not aware of any feature that requires me to accelerate or brake to prevent the car from stopping itself.

> What behavior are you referring to?

Automatic Emergency Braking. You cannot turn off AEB persistently.

> I'm not aware of any feature that requires me to accelerate or brake to prevent the car from stopping itself

Before the car emergency brakes, it will warn you via "Forward Collision Warning"; the screen will show the object it thinks you're about to hit in red. You can set this to "Late" to reduce false positives -- but if you do, you'll have less time to take action yourself. So now I set it to Early.

After a FCW, you have a small amount of time to do something before the car will do something for you. The M3 manual describes AEB here:

https://www.tesla.com/ownersmanual/model3/en_us/GUID-8EA7EF1...

It also explains "Automatic Emergency Braking is always enabled when you start Model 3. To disable it for your current drive, touch Controls > Autopilot > Automatic Emergency Braking."

This article is about autopilot phantom braking, not AEB. I've never had AEB trigger, or heard of it triggering when it shouldn't, but maybe I'm unaware.

Phantom braking includes self-driving/cruise and ADAS, e.g. "What is phantom braking"

> Phantom braking is a term used to describe when an advanced driver assistance system (ADAS) – or a self-driving system – applies the brakes for no good reason

(AEB is part of ADAS)

i had it trigger twice: once to prevent a frontal crash that would have been my fault, and once during a storm. i am very glad that it is there; works extremely well.

Can you put some tape over the sensors?

Can't speak for OP, but I'm supposed to be paying attention at all times while autopilot is enabled; as soon as I feel the vehicle may phantom brake, I apply more pressure to the accelerator to maintain speed.

I believe the NHTSA is going to require Tesla retrofit radar on all vehicles to mitigate their Tesla Vision functionality deficiency.

(submitted lengthy dash cam videos and accelerometer data to the NHTSA as a complaint)

I have an early release Model 3 with radar. I suspect they stopped using the radar in a software update once they started releasing Model 3s without radar, as it didn't have this jerky stopping behavior before that.

Happens often on my Y, does not happen on my legacy S and X (circa 2018 and 2019) that are equipped with Continental radar front facing radar. I believe even current S and X vehicles are still getting radar installed, so Tesla is only being cheap on the 3 and Y to keep moving them at volume as a supply chain mitigation.

Tesla stopped putting radar units in new Model S/X in February this year.

https://www.tesla.com/support/transitioning-tesla-vision

My information is outdated, I appreciate the correction.

vehicles from 2019 being referred to as "legacy" is the most infuriating thing I've read today.

Of course no offense to OP, i've heard it referred as such by others and I know it's not literal. But it's maddening to me though that a vehicle that is still under warranty has a moniker that traditionally means end of life/support in software.

With most other cars, it becomes legacy as soon as you drive it off the lot and they release the next model year

At least Tesla mostly keeps updating their older car’s software.

(bit late on the reply, sorry)Caveat; I think EV are far superior to ICE vehicles in every measurable metric.

That said, I don't understand what you mean. 9.9/10 of new, non motorsports ICE vehicles are backed by warranty bumper to bumper for 60-100k miles. Further, the parts/labor pipeline is massive.OEM/aftermarket keep producing parts for years after the vehicle's generation stops being sold as new.

In the case of Tesla and some Boutique EVs, there is no aftermarket, and there's litigation from Tesla if you try to repair/produce aftermarket parts. "At least tesla mostly keeps updating their older car's software" is not a positive. It should be guaranteed for 60k-100k miles, and the aftermarket should be allowed to repair it.

Tesla makes their vehicles "legacy" on purpose.

I’m convinced they ditched radar because they were having big supply chain constraints with radar, and then Musk convinced himself that Machine Vision with AI is the path forward anyway and decided to rip the bandaid off and address both issues at the same time. (& I really do think he believes that because he obsessed over the AI safety thing in the past in a way I think is unforced and a little silly and pretty clearly falsified at this point.) I do think radar ought to help, at least in principle. Although they probably can eventually get vision to be better than Vision+Radar used to be, although I STILL think it’d be better off also with radar (and perhaps a different, better kind of radar unit).

> I’m convinced they ditched radar because they were having big supply chain constraints with radar, and then Musk convinced himself that Machine Vision with AI is the path forward anyway and decided to rip the bandaid off and address both issues at the same time.

Yes, that and his attitudes towards LIDAR seem like motivated reasoning / sour grapes. "LIDAR is too expensive to put in cars I'm selling today, therefore it isn't good anyway." (I can't reach the grapes, therefore they're sour and I didn't want them anyway.) Why else would he criticize LIDAR with inane arguments about LIDAR not being able to read street signs, as though anybody is suggesting LIDAR-only rather than LIDAR+Optical?

I'm convinced they ditched radar because Musk wanted to make more money.

Sort of like how GM and Ford used to have actuaries work out the cost of a fuel tank that wouldn't incinerate the occupants in a crash vs legal settlement costs.

Except minus actuaries and instead just Musk figuring "Well I've gotten away with everything else, why not this as well?" and sadly being right.

From ignoring COVID health orders to flashing his dick to repeated stock manipulation to making billions in a company that stole people's money constantly "because we're not a bank", Musk hasn't faced any significant repercussions for anything immoral or illegal he's ever done.

>Vision+Radar

I would imagine that multiple systems with a majority wins type of thinking would be ideal. Would probably need another system for it to be an odd number.

Radar is only turned off if you are accepted into the full self driving beta and turn it on. Then it switches over to full vision.

I believe they're still using radar in cars where the hardware exists (unless you have FSD, in which case it's using vision only).

You accelerate harder to compensate for a car that brakes too quickly? This is considered normal in Tesla-land?

Your fix reminds me of this: https://xkcd.com/1172/

Tesla isn't going to take the vehicle back, nor would I sell the car to someone else, so I am left to complain loudly to regulators, which I admit is a guilty pleasure (especially when I have lucked into having standing).

I also opted out of arbitration for all of my vehicles [1], for obvious reasons. I am simply attempting to make lemonade from lemons.

[1] https://old.reddit.com/r/teslamotors/comments/8vxnz0/psa_for...

Hah, one time my computer had periodic hiccups where the mouse cursor update rate would slow down and back to normal within a second, it almost turned me into the Hulk... I can't imagine driving a car with that problem.

My vision-based Tesla rarely if ever experiences phantom braking unlike my previous radar-equipped Model 3 (it was pretty common in 2018 / 2019).

All Teslas are "vision-based" now. They no longer use the RADAR even in cars that have it.

This is probably so they can have only one software build rather than supporting one with and one without RADAR. And also so that they can say the RADAR isn't needed anyway.

TL:DR; Radar is not the silver bullet here

>(submitted lengthy dash cam videos and accelerometer data to the NHTSA as a complaint)

Did you upload video to them, or post a link from a streaming site? It would be interesting to see the analytics that a streaming site can provide to know if anyone from the gov't ever actually looks at the video vs the blind upload to a black hole.

I had much worse results with radar several years than I do now with the FSD that doesn’t use radar anymore, so I don’t think radar is the necessary solution here

For what it's worth, I've tried and failed to reproduce this on my Model 3. I've driven next to trucks, motorcycles, under overpasses, under very-low overpasses, near pedestrians, and even passed camels and horses on the side of the road. No phantom braking.

That said, when using the lane-assist, I do prefer to keep my foot on the accelerator pedal anyway. To increase range, I try not to get into regen at all unless I actually do want to brake. I feel that the cruise control is to strict in keeping a particular speed in hilly areas, and I live and work in hilly areas. Let the vehicle speed up in the dips and slow down on the peaks, just like all the other cars (probably manually driven) are doing.

Agreed this always bothered me about cruise control as well. Particularly for electric cars I am wishing for a dedicated physical toggle or slider to instantly disable or dial-back regen for the times I want to coast.

Regen in Prius managed by your foot pressure on brake pedal. I wonder why would anybody do it differently.

Prius will regen slowly when you take your foot off the gas. Just like a Tesla. The difference is that Teslas regen aggressively, so you really notice the deceleration, whereas a Prius will not start major regen braking until you press on the brakes.

If you have the energy flow view up on the screen, you can see the power going from the motor/generator to the battery when you release the gas.

Hyundai cars use the little paddles behind the steering wheel to control regen level. It's pretty nice to be able to coast when you want to.

We'll know that AI is really coming along once cars also break to gawk at camels.

If the accelerator pressed at all, it wont break automatically. Not sure if you're pressing it or just hovering on it, but that might be why.

That's why I mentioned that I've tried to reproduce the issue. I would deliberately let the computer handle speed even though I personally prefer to, so that I could experience the phantom braking firsthand.

I was driving to Las Vegas with my father (in my Model Y) and I was telling him, "I've never experienced this so-called phantom braking..." A literally 3 seconds later I experienced it and few times later in the next hour or so.

It's sentient

Cool. Adding "are they trying to reproduce an Autopilot bug they read about online?" to the list of thoughts I have when encountering a Tesla on the road.

That's actually pretty funny. The Tesla is definitely a different type of car.

>I feel that the cruise control is to strict in keeping a particular speed in hilly areas, and I live and work in hilly areas.

This is always an issue with underpowered ICE vehicles and cruise control, less-so with the 7 or 8 gear transmission, but still. They don't have enough power to maintain velocity, so constantly shifting, speed up, slow down...

I don't drive a Tesla, but my car is a newer model with "smart" cruise control. It freaks out whenever there's a slight curve in the road and there's a car in the next lane over. Do Teslas have the same issue?

No, only if the lane markings aren't visible. It's pretty good at identifying where the lanes are.

> No, only if the lane markings aren't visible

That's... most of Canada, thanks to the snowplows. Good to know.

Besides the plows and grit, this CBC article claims the paint they choose has something to do with it:

> Most of the paint is environmentally friendly but being water-based, it rarely lasts more than a year, especially on the province's busiest roads and highways.

> "The paint used for highway striping eventually wears down as a result of the wear and tear from vehicle traffic as well as the effects of necessary winter maintenance activities," said a spokesperson with the Department of Transportation and Infrastructure.

> The provincial government only uses oil-based paint in cold weather. The bulk of road work is completed during the summer months, so it seems unlikely many fresh painted lanes this year will survive the winter.

https://www.cbc.ca/news/canada/new-brunswick/disappearing-ro...

I'm not sure about the paint composition matter, but at least I can attest to the road lines in Canada being very poor. I've driven most of the Trans-Canadian Highway (all of it west of Quebec) and the line paint was virtually nonexistent for much of even this road.

You can be even more "environmentally friendly" by doing away with the markings, or even the paving...

The markings here seem to be some sort of dense plastic material and don't wear much.

> The markings here seem to be some sort of dense plastic material and don't wear much.

I think those markings might be the epoxy based "golden oatmeal" this article mentions (https://vancouversun.com/news/local-news/b-c-hunts-for-a-dur...) Durable but expensive.

> Meanwhile, the province does have an alternative it has been using on roads where visibility, geography and weather make for dangerous conditions, such as parts of the Coquihalla Highway. Crews grind out a line-sized trench in the pavement and pour a clumpy epoxy-plastic paint nicknamed “golden oatmeal” that bonds to the asphalt using the same material as dentures. Because it sits just below the rest of the pavement, it better withstands wear. “The problem is to do that is extremely cost prohibitive,” said Stone. “It’s very pricey.”

The most robust option for you then would almost certainly be a map-focused option, like VW's newest Travel Assist ("swarm data".)

Or, ya know, an older car that's got fewer bugs than features. Alas, my spouse won't go for a car that actually works reliabily.

This only happened to me in a Model S whenever it was cresting any kind of hill that it couldn't see over (which can be pretty minor rollers to big hills). It would usually start swerving to the right.

Happens to me all the time as well, I've got FSD (not the beta, the highway version, because apparently I take turns too quickly) and I have to be alert to bury the accelerator in case this happens on the highway. It's rare enough that I'm never quite prepared, but frequent enough that I know to be on my toes.

I've never seen it happen when I was following someone, I bet the software is biased to follow the vehicle in front even if one of these events happen. It happens to me when I'm headed up a hill and there is an overpass on the far side of the hill, or I'm passing a low overhead sign. I can understand why radar thinks it's about to slam into a wall, from the radar's low slung perspective I'm sure it just sees a barrier ahead. Considering Tesla's early penchant for driving right into the side of a truck, I do somewhat prefer the sudden braking.

I think the takeaway should be that autopilot cannot be generalized. You can't say it's better or worse under all situations than an average driver. Sure there are situations that it's clearly better or worse than an average driver like driving on a pretty straight freeway for hours long or driving on a twisty road without clear lane markings.

The problem arises with ambiguous situations like phantom breaking. Is it phantom breaking because the tree overhangs are too close to the surface of the road, the sun is shinning directly into one of the cameras or is there smudge on the camera lens? For this category of problems we're likely to see both improvements and further regressions. The ambiguity will bifurcate into clearly worse and clearly better than average human driver categories. This is the part we need patience for the technology to improve.

The clearly worse than human driver category may be an intractable set of problems and that's what we should judge viability of self-driving technology base off of.

>Seems real easy to get rear-ended.

Which, in this age of cheap ubiquitous dash-cams, isn't nearly as likely to be the "inconvenient waste of time but zero financial risk" deal it used to be

Edit: Since apparently this needs explaining, insurers will consider evidence and happily doll out blame to a party that does something dumb in proportion to their fault (with slight variations per differences in law from state to state). The fact that said dumbness results in the back of your car getting hit with the front of another only matters in the base case in which no other reliable information about the situation is available. In the case of a car that just stops in the roadway with no reason to do so some of the blame is likely to land on the driver thereof. Insurers are well aware that the rules of the road are built around redundant requirements so that crashes don't happen when one party can't or won't hold up their end. Infantile "but the other guy is responsible for.." arguments don't tend to hold much water with them when there's evidence (video or otherwise) that in the events that lead up to the accident your hand was no more forced than the other guy's were because both drivers are still bound by whatever the default responsibility to operate their vehicles in a safe manner is (wording varies by state).

I don't understand what you mean. You seem to be implying that if a driver rear-ends you he can use his dash-cam to show you were at fault? Most places I've driven it is the following car's responsibility to maintain a safe distance which includes being able to stop if the car you are following suddenly stops. Yes, brake checking is a thing and could complicate any civil suit, but mechanical (now software) failure wouldn't be that.

Yeah they should be following further back. There's no excuse to rear-ending somebody. If your car can't stop as fast as a heavy-ass Tesla, you need to be following further back. If you hit someone brake checking you, you were following too close.

You never know when someone might need to do a full, 100% brake slam to avoid something.

You never know when someone might need to do a full, 100% brake slam to avoid something.

I don't know about you, but I usually look beyond the car in front and possibly the one in front of that one too in order to anticipate braking. If it's all clear ahead and the one immediately in front suddenly brakes hard, I don't think it's clear that it isn't culpable.

To say nothing of the "inconvenience" to the driver who wasn't at fault but would have been assumed to be.

In which jurisdiction would the rear-ending driver not be at fault? He was either inattentive or failed to maintain proper distance. Sure, driving too close is common, but that doesn't make it right

The car behind who rear ends the car in front has a presumption of being at fault, but if there is evidence to show the car in front caused the accident (say, by brake checking them) then that can change the outcome.

Before dash cams, it was very rare for the car behind to be able to show any proof otherwise, so they were usually at fault unless there were credible witnesses of the brake checking.

But no, you can't just randomly threshold brake in the middle of the highway for no reason and expect to blame the car behind for your actions (or the actions of your car).

Surely rear ending a misbehaving Tesla is still the fault of the following car?

Or am I misunderstanding you?

Where I live (not the US) the only way rear-ending would be the tailing vehicle's fault is if the front vehicle was running in reverse. Otherwise, it's your responsibility to maintain a safe distance form the vehicle ahead, and one should assume this vehicle may stop unexpectedly. You're always at fault if you rear-end someone.

IIRC from law school (in the US), the driver of the back car would be rebuttably presumed to be at fault. This presumption could be rebutted, for example, if it were shown that the front car braked hard for no reason whatsoever.

> Which, in this age of cheap ubiquitous dash-cams, isn't nearly as likely to be the "inconvenient waste of time but zero financial risk" deal it used to be

Chance of permanent injury or death is not negligible. e.g. get rear ended by a semi, or just suffer from whiplash that doesn't go away.

> the rules of the road are built around redundant requirements so that crashes don't happen when one party can't or won't hold up their end.

Exactly; this is why brake-checking is illegal. The person behind you has a responsibility to keep a safe distance, but you also have a responsibility to not drive like a lunatic. If the dash-cam footage shows you brake-checking somebody right before the crash, don't expect to get off scot-free by blaming the guy you were fucking with.

More bugs flying closer to the Summer?

I guess that would fit "bug" definition?

Reply on news.ycombinator.com