4 ms·

A car stopped on the highway with no warning lights or anything in center lane, at night... I'm not sure I'd be able to spot and react in time, this is what I w

A car stopped on the highway with no warning lights or anything in center lane, at night... I'm not sure I'd be able to spot and react in time, this is what I would expect radar and other sensors on car to pick up and break on... those also failed...

pants2 3y ago
Especially on Texas highways where speed limits exceed 80mph, you'd have to be very alert and likely have to swerve over into the next lane (like the other driver did). At 80mph, the stopping distance of an average car is around 300 feet once the brake is fully engaged. That exceeds most car radar systems. And with no warning lights the camera won't do much good either.
- _dark_matter_ 3y ago
  This seems insane, are you telling me that these cars will travel at a speed whose distance is longer than the radar can detect? That is _guaranteeing_ crashes.
  - JumpCrisscross 3y ago
    > are you telling me that these cars will travel at a speed whose distance is longer than the radar can detect? "Low beams or dipped lights should shine about 150 to 200 feet ahead, while high beams or brights should shine about 350 to 400 feet ahead" [1]. Would it be customary for someone on that highway to have their high beams engaged? [1] https://autoily.com/how-far-should-headlights-shine/ https://autoily.com/how-far-should-headlights-shine/
    - toast0 3y ago
      High beams are really for rural roads with very little traffic. If there are at least three lanes of traffic in one direction[1] and enough traffic that a car in front was able to see the collision in their rear view mirror, high beams are not advised. Using them in this situation will cause major glare from mirrors of the drivers in front, and possibly for the drivers in the opposing direction. [1] as indicated by the stopped vehicle being reported in the center lane
      - JumpCrisscross 3y ago
        Which makes the radar range being less than the stopping distance less salacious.
        MBCook 3y ago
        Plus the radar is for gauging relative speed so the car can speed up to the set point if safe or slow down if the car ahead is. It is not for finding stopped stuff in the middle of the road at high speed. I hear there are too many false positives for that to be done.
    - burkaman 3y ago
      I mean yeah if you're on a pitch black highway and you can't see anything outside your headlight beams, you probably shouldn't be going 80 even if that's the speed limit.
      - bongodongobob 3y ago
        No idea where you live but this is probably 99% of highways in the US. Where do you live that the highways are illuminated?
        burkaman 3y ago
        You can't go 80 on most highways.
        toast0 3y ago
        No street lights doesn't imply pitch black. It may imply poorly illuminated. I can't find a date, only a time, so I can't guess at lunar illumination or cloud cover. But we don't know how many other vehicles were on the road and what light they were casting. The bystander who reported witnessing the crash was within visual distance, so couldn't have been too far ahead of the MachE. It wasn't reported if there were any other vehicles. If you have enough vehicles on the road (with their lights on) lack of overhead illumination isn't too significant.
        Free-is-Freedom 3y ago
        Canada
        progman32 3y ago
        So be it. Going 80+ at night might not be a good idea on most roads.
  - pants2 3y ago
    Some vehicles (like my Subaru) offer automatic emergency steering that can save you when there's not enough distance to brake. The Mach-e doesn't have that per my quick Google (they have some assisted thing but it requires manual steering)
    - MBCook 3y ago
      It does not. It has some kind of assist that is supposed to help you swerve fast enough and correct back to normal instead of overcorrecting. It’s designed to fix driver inputs during a panic. You’re right it doesn’t do anything on its own.
- user_7832 3y ago
  > At 80mph, the stopping distance of an average car is around 300 feet once the brake is fully engaged. That exceeds most car radar systems. And with no warning lights the camera won't do much good either. I think this is a pretty important point for any well-built self-driving software. Does anyone know if radar advancements could help increase this?
  - MBCook 3y ago
    My understanding is no. The big problem is that a stopped vehicle looks exactly the same to the radar as any other stationary object. So if it sees something stationary it could be a stopped vehicle or it could be a reflection from a road sign. Or a lip in the pavement. Or something else like that. Basically from what I’ve heard if it were to try and stop whenever it saw something stopped ahead it would constantly slam on the brakes unnecessarily. So stationary things have to be ignored, and it can’t save you from them. They all suffer from this. The only solution I’ve heard of is LIDAR but obviously that’s a huge step up.
modeless 3y ago
This is why cars are required to have red retroreflectors on the back, so even if their lights are off you can still see red lights as long as your own headlights are on. I wonder why this failed.
- Grazester 3y ago
  Exactly. It's easy to avoid a stationary object on the road in normal visibility out if your headlights work a damn. Maybe I am just too accustomed to driving on rural third world roads where cows wander at night.
  - adriancr 3y ago
    From experience, coming up to traffic jams on highways in the past, you can get deceived by cars ahead either stopped or slowing down - you dont expect that, especially after long monotonous driving, hence need for warning lights.
    - MBCook 3y ago
      Especially if they don’t slow down/swerve until the last second. If they had done it earlier you would’ve had more time to start noticing something was going on.
    - Grazester 3y ago
      Indeed. I have never driven more than 4-5 hours at a time. I find driving very taxing for me. I tend to be very focused on the road and drive like everyone and everything is trying to kill me. For this reason I don't use driving aids either not even standard cruise control.
      - MBCook 3y ago
        I find they help physically. After a few hours of driving I feel less tired and need to rest arms/legs physically. The mental toll is nearly unchanged. So when you stop I feel it’s easier to walk around and shop or whatever since I haven’t been applying as much force constantly. But you still need that mental brake.
toast0 3y ago
This probably needs to be added to a safety test suite. Either for the cars or for drivers. Most adapative cruise control systems explicitly ignore stationary objects while at highway speeds. A vehicle immediately ahead that stops will be detected and responded to. A vehicle that did not move while in sensor range will be ignored.
- pirate787 3y ago
  Also seems like the stopped car could emit a signal that self-driving cars could pick up.
  - MBCook 3y ago
    That could be abused really easily if anyone ever figured out how. It’s have no idea if the risk is worse than the reward or not.
    - Free-is-Freedom 3y ago
      Look into Kia Boys and you will know that this idea would never work in modern USA culture
mdavidn 3y ago
Radar struggles to identify stationary vehicles. Their reflected signals hide in noise from road signs, roadside vegetation, and the road surface itself.
- lutorm 3y ago
  It's worse than that, I think. The typical radar beam is so wide that it can't discriminate between in the road and near the road, so the Doppler selection is the only reason it even works at all. This is very noticeable on our car when you observe how far away laterally a car you've been following has to turn, e.g. when it takes an offramp, before the ACC ignores it.
  - t0mas88 3y ago
    What brand and model year is that? The first (15 years ago) system from BMW did that too, but the newer ones (2019 model, don't know about the years in between) know which lane the other car is in. There is a setting on European models on whether to overtake on the right or not, so it knows the traffic ahead is in your lane or in the next lane over.
SkyPuncher 3y ago
I came across this a few weeks ago on a snowy highway. Car way in front of me had its hazards on in the right lane. The center lane was clear, so I decided to make a lane change. I assumed this car was just moving slow in bad conditions, but it was actually completely stopped in the right most lane. I didn’t realize that until I passed it. Given the conditions, it would have been extremely hard to avoid this car if I had not proactively changed lanes. There was just absolutely no reason this car should have been stopped in a lane when it could have gotten to th shoulder.
hakdbha 3y ago
[dead]
choppaface 3y ago
> A car stopped on the highway with no warning lights or anything in center lane, at night Basically every uber driver does this, double parking wherever they want. So L2 systems need uber detection.
- TylerE 3y ago
  I have literally never seen a highway with parking.
  - choppaface 3y ago
    I have literally never seen an uber use a parking spot.

pants2 3y ago

Especially on Texas highways where speed limits exceed 80mph, you'd have to be very alert and likely have to swerve over into the next lane (like the other driver did). At 80mph, the stopping distance of an average car is around 300 feet once the brake is fully engaged. That exceeds most car radar systems. And with no warning lights the camera won't do much good either.

_dark_matter_ 3y ago
This seems insane, are you telling me that these cars will travel at a speed whose distance is longer than the radar can detect? That is _guaranteeing_ crashes.
- JumpCrisscross 3y ago
  > are you telling me that these cars will travel at a speed whose distance is longer than the radar can detect? "Low beams or dipped lights should shine about 150 to 200 feet ahead, while high beams or brights should shine about 350 to 400 feet ahead" [1]. Would it be customary for someone on that highway to have their high beams engaged? [1] https://autoily.com/how-far-should-headlights-shine/ https://autoily.com/how-far-should-headlights-shine/
  - toast0 3y ago
    High beams are really for rural roads with very little traffic. If there are at least three lanes of traffic in one direction[1] and enough traffic that a car in front was able to see the collision in their rear view mirror, high beams are not advised. Using them in this situation will cause major glare from mirrors of the drivers in front, and possibly for the drivers in the opposing direction. [1] as indicated by the stopped vehicle being reported in the center lane
    - JumpCrisscross 3y ago
      Which makes the radar range being less than the stopping distance less salacious.
      - MBCook 3y ago
        Plus the radar is for gauging relative speed so the car can speed up to the set point if safe or slow down if the car ahead is. It is not for finding stopped stuff in the middle of the road at high speed. I hear there are too many false positives for that to be done.
  - burkaman 3y ago
    I mean yeah if you're on a pitch black highway and you can't see anything outside your headlight beams, you probably shouldn't be going 80 even if that's the speed limit.
    - bongodongobob 3y ago
      No idea where you live but this is probably 99% of highways in the US. Where do you live that the highways are illuminated?
      - burkaman 3y ago
        You can't go 80 on most highways.
      - toast0 3y ago
        No street lights doesn't imply pitch black. It may imply poorly illuminated. I can't find a date, only a time, so I can't guess at lunar illumination or cloud cover. But we don't know how many other vehicles were on the road and what light they were casting. The bystander who reported witnessing the crash was within visual distance, so couldn't have been too far ahead of the MachE. It wasn't reported if there were any other vehicles. If you have enough vehicles on the road (with their lights on) lack of overhead illumination isn't too significant.
      - Free-is-Freedom 3y ago
        Canada
      - progman32 3y ago
        So be it. Going 80+ at night might not be a good idea on most roads.
- pants2 3y ago
  Some vehicles (like my Subaru) offer automatic emergency steering that can save you when there's not enough distance to brake. The Mach-e doesn't have that per my quick Google (they have some assisted thing but it requires manual steering)
  - MBCook 3y ago
    It does not. It has some kind of assist that is supposed to help you swerve fast enough and correct back to normal instead of overcorrecting. It’s designed to fix driver inputs during a panic. You’re right it doesn’t do anything on its own.
user_7832 3y ago
> At 80mph, the stopping distance of an average car is around 300 feet once the brake is fully engaged. That exceeds most car radar systems. And with no warning lights the camera won't do much good either. I think this is a pretty important point for any well-built self-driving software. Does anyone know if radar advancements could help increase this?
- MBCook 3y ago
  My understanding is no. The big problem is that a stopped vehicle looks exactly the same to the radar as any other stationary object. So if it sees something stationary it could be a stopped vehicle or it could be a reflection from a road sign. Or a lip in the pavement. Or something else like that. Basically from what I’ve heard if it were to try and stop whenever it saw something stopped ahead it would constantly slam on the brakes unnecessarily. So stationary things have to be ignored, and it can’t save you from them. They all suffer from this. The only solution I’ve heard of is LIDAR but obviously that’s a huge step up.

modeless 3y ago

This is why cars are required to have red retroreflectors on the back, so even if their lights are off you can still see red lights as long as your own headlights are on. I wonder why this failed.

Grazester 3y ago
Exactly. It's easy to avoid a stationary object on the road in normal visibility out if your headlights work a damn. Maybe I am just too accustomed to driving on rural third world roads where cows wander at night.
- adriancr 3y ago
  From experience, coming up to traffic jams on highways in the past, you can get deceived by cars ahead either stopped or slowing down - you dont expect that, especially after long monotonous driving, hence need for warning lights.
  - MBCook 3y ago
    Especially if they don’t slow down/swerve until the last second. If they had done it earlier you would’ve had more time to start noticing something was going on.
  - Grazester 3y ago
    Indeed. I have never driven more than 4-5 hours at a time. I find driving very taxing for me. I tend to be very focused on the road and drive like everyone and everything is trying to kill me. For this reason I don't use driving aids either not even standard cruise control.
    - MBCook 3y ago
      I find they help physically. After a few hours of driving I feel less tired and need to rest arms/legs physically. The mental toll is nearly unchanged. So when you stop I feel it’s easier to walk around and shop or whatever since I haven’t been applying as much force constantly. But you still need that mental brake.

toast0 3y ago

This probably needs to be added to a safety test suite. Either for the cars or for drivers. Most adapative cruise control systems explicitly ignore stationary objects while at highway speeds. A vehicle immediately ahead that stops will be detected and responded to. A vehicle that did not move while in sensor range will be ignored.

pirate787 3y ago
Also seems like the stopped car could emit a signal that self-driving cars could pick up.
- MBCook 3y ago
  That could be abused really easily if anyone ever figured out how. It’s have no idea if the risk is worse than the reward or not.
  - Free-is-Freedom 3y ago
    Look into Kia Boys and you will know that this idea would never work in modern USA culture

mdavidn 3y ago

Radar struggles to identify stationary vehicles. Their reflected signals hide in noise from road signs, roadside vegetation, and the road surface itself.

lutorm 3y ago
It's worse than that, I think. The typical radar beam is so wide that it can't discriminate between in the road and near the road, so the Doppler selection is the only reason it even works at all. This is very noticeable on our car when you observe how far away laterally a car you've been following has to turn, e.g. when it takes an offramp, before the ACC ignores it.
- t0mas88 3y ago
  What brand and model year is that? The first (15 years ago) system from BMW did that too, but the newer ones (2019 model, don't know about the years in between) know which lane the other car is in. There is a setting on European models on whether to overtake on the right or not, so it knows the traffic ahead is in your lane or in the next lane over.

SkyPuncher 3y ago

I came across this a few weeks ago on a snowy highway. Car way in front of me had its hazards on in the right lane. The center lane was clear, so I decided to make a lane change. I assumed this car was just moving slow in bad conditions, but it was actually completely stopped in the right most lane. I didn’t realize that until I passed it. Given the conditions, it would have been extremely hard to avoid this car if I had not proactively changed lanes. There was just absolutely no reason this car should have been stopped in a lane when it could have gotten to th shoulder.

hakdbha 3y ago

[dead]

choppaface 3y ago

> A car stopped on the highway with no warning lights or anything in center lane, at night Basically every uber driver does this, double parking wherever they want. So L2 systems need uber detection.

TylerE 3y ago
I have literally never seen a highway with parking.
- choppaface 3y ago
  I have literally never seen an uber use a parking spot.