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I've also read enough complaints about inexplicable emergency braking activation to say that all drivers should be aware these are on the road. You need to con

I've also read enough complaints about inexplicable emergency braking activation to say that all drivers should be aware these are on the road. You need to consider that now random new cars may execute a "brake check" maneuver in situations where you would never anticipate a human to have done the same thing.

jon_richards 9y ago
Sudden curves in the road when there are parked cars is the biggest issue for mine. I think it plots a path based on how my wheel is turned. When there's a 10-15 degree kink in the road, I can't turn early or I'll cross the center line, so it thinks I'm going to continue straight into a parked car. Hasn't brought me to a complete stop, but it could certainly mess with a tailgater.
- suprfnk 9y ago
  > but it could certainly mess with a tailgater. Unless the tailgater also has this system!
  - more-coffee 9y ago
    Now I've got a hilarious image in my mind of a bunch of modern cars taking turns to accelerate, abruptly brake, accelerate, brake... The future is now.
    - fantasticsid 9y ago
      That’s called a phantom jam, happens right now on 101 with humans;) Won’t happen if only people don’t tailgate.
      - more-coffee 9y ago
        [offtopic]Yep. I'm usually in the "slow lane" bemidst truckers, amusing myself by watching the Giant Car Worm on the "fast lane".[/offtopic]
      - jon_richards 9y ago
        I imagine phantom jams will pretty much be a thing of the past once we reach a certain percentage of cars running auto-braking cruise control. Have there been studies on what that percentage is?
        saltcured 9y ago
        You have to characterize the control behavior to model whether the system will dampen its response or create a sustained or amplifying feedback loop as all the agents interact. These traffic jams are essentially standing waves propagating between agents. You don't erase the standing wave by having everybody maintain a fixed following distance or mimicking the speed of their leader. You need to predict future changes and allow the space to contract to help smooth out the transient disruptions and slowly rebound without over-shooting. You want each following car to react less than the previous and have a weaker deceleration/acceleration curve. Unfortunately, I have noticed increasingly absurd feedback loops in long distance routes here in CA. As a user of conventional cruise control, I can't help but notice how frequently I now have to intervene to adjust speeds in relatively light traffic conditions. On long drives like LA-SF via I-5, these yo-yo drivers are my new nemesis. I don't know if it is due to their use of adaptive cruise controls or a more basic loss of attention or self-awareness. For example, I see packs of cars with speeds oscillating between 55-80 MPH when conditions should easily allow a steady cruise at 75 MPH.
      - lsaferite 9y ago
        Actually, if everyone perfectly tailgated out of a rolling jam, then they'd all be fine. Instead you get people that let a large enough gap open for them to accelerate faster than the car in front, then they have to brake when they reach that lead car again. This slinky effect is what causes those rolling traffic jams and why they can break them by slow-rolling in from of the jam to force everyone to stop the slinky effect.
eknkc 9y ago
Our two cars both have decent autonomous breaking tech. They did activate in actual risks a couple of times. At least once one prevented a certain crash. They act up rarely. Just some anectodes; One of them thinks I will drive into a wall when I’m approaching a 90degree turn with a wall. Does the break check from time to time. Nothing weird at high speeds for now. Other had a single break check at high speed, there was nothing in front so the sensors somehow messed up I guess. It braked for something like 100ms, at least it felt like that. Then kept driving normally. But even that was scary.
donkeyd 9y ago
My car does get triggered by lines on the street in a specific area. However, Dutch law says you're supposed to drive at a distance where you can anticipate that the car in front of you can go full stop at any time, so I'm not sure why this should cause people to do that and not the fact that they already should.
- Angostura 9y ago
  > However, Dutch law says you're supposed to drive at a distance where you can anticipate that the car in front of you can go full stop at any time, so I'm not sure why this should cause people to do that and not the fact that they already should. You've just explained why autonomous braking is completely unnecessary. People are perfect, never make mistakes and never assume that the car in freely-flowing traffic ahead of them won't stamp on the brakes for no apparent reason.
fantasticsid 9y ago
I’ve thought about this and and I think the best thing to do here is to relentlessly keep a long, safe distance from vehicles ahead. There are just things you can’t possibly see that the driver before you can.(a puppy/squirrel/whatever that he wants to avoid killing, you can’t possibly know). You can’t anticipate what a human will do here. You also give yourself a buffer when vehicle ahead have an emergency stop - imagine there’s a truck behind you. I guess what I’m saying is these ‘brake checks’ are welcome, even if they only serve to educate people.
- cm2187 9y ago
  Agree. In Europe, if you follow the recommended safety distance, you always have the time to brake if anything happens to the car in front of you. The problem is that people do not follow them.
  - ProblemFactory 9y ago
    Following the recommended safety distance (2-3 seconds of travel distance if I recall correctly) is quite difficult in moderate to heavy traffic. If you leave a large enough gap with the car in front, then people will merge into that gap. If you then slow down to create a new gap - people will overtake and merge in again. You end up travelling slower than the rest of traffic, with people overtaking and merging, which creates dangers in itself.
- dolzenko 9y ago
  Problem is everybody else have to behave similarly, otherwise other cards just take the place of that safe distance.
  - carlmr 9y ago
    It might be annoying, but even if a few cars get in between you usually don't lose much by getting a safe distance again.
    - NLips 9y ago
amelius 9y ago
> You need to consider that now random new cars may execute a "brake check" maneuver in situations where you would never anticipate a human to have done the same thing. This is to persuade you to also buy a car with new brake tech ;)
gambiting 9y ago
The car will never emergency break as long as you keep your foot on the throttle. My Merc has beeped at me couple times where it thought I was going to collide with something, but because I kept my foot down it didn't actually start breaking - the system only activates if you let go of the gas.
- thrav 9y ago
  The Subaru actually interprets this as you accelerating into a wall and takes over. You have to let off and then reapply for it to say, “ok, they clearly know something I don’t.”
greenhatman 9y ago
You should be expecting any driver to do an emergency stop right in front of you. I've learned the hard way not to expect anything from other drivers on the road. Make sure your following distance is such that you have enough time to react to completely oblivious driving behaviour from other drivers.
- lsaferite 9y ago
  > Make sure your following distance is such that you have enough time to react to completely oblivious driving behavior from other drivers. While I fully endorse this ideal, the reality of driving in high-traffic cities is that it's impossible. Every time you adjust to leave proper space, someone will come along and appropriate your safety buffer. When you slow again to allow enough space, the pattern repeats.
  - icc97 9y ago
    Tragedy of the driving commons. In such situations I just drive slightly under the distance I would normally keep, but then just back off those that do barge in.
- saltcured 9y ago
  I didn't say we should take these braking systems off the road, but I do think drivers need to adapt to their presence. Personally, I am happy my 2017 vehicle does not have it and the ones on the market will probably be much improved by the time I consider a replacement. As others discussed throughout this thread, there are many situations where drivers violate the safe following distance rules. Aside from the lack of attention scenarios, I think many drivers take calculated risks to temporarily reduce their following distances while performing some other maneuver. They should incorporate this new idea of neurotic automatic-braking systems into this risk calculus, so they don't get caught in a situation they cannot handle. While we have a mixture of different vintage cars (and drivers!), I am afraid we will remain living in interesting times...

jon_richards 9y ago

Sudden curves in the road when there are parked cars is the biggest issue for mine. I think it plots a path based on how my wheel is turned. When there's a 10-15 degree kink in the road, I can't turn early or I'll cross the center line, so it thinks I'm going to continue straight into a parked car. Hasn't brought me to a complete stop, but it could certainly mess with a tailgater.

suprfnk 9y ago
> but it could certainly mess with a tailgater. Unless the tailgater also has this system!
- more-coffee 9y ago
  Now I've got a hilarious image in my mind of a bunch of modern cars taking turns to accelerate, abruptly brake, accelerate, brake... The future is now.
  - fantasticsid 9y ago
    That’s called a phantom jam, happens right now on 101 with humans;) Won’t happen if only people don’t tailgate.
    - more-coffee 9y ago
      [offtopic]Yep. I'm usually in the "slow lane" bemidst truckers, amusing myself by watching the Giant Car Worm on the "fast lane".[/offtopic]
    - jon_richards 9y ago
      I imagine phantom jams will pretty much be a thing of the past once we reach a certain percentage of cars running auto-braking cruise control. Have there been studies on what that percentage is?
      - saltcured 9y ago
        You have to characterize the control behavior to model whether the system will dampen its response or create a sustained or amplifying feedback loop as all the agents interact. These traffic jams are essentially standing waves propagating between agents. You don't erase the standing wave by having everybody maintain a fixed following distance or mimicking the speed of their leader. You need to predict future changes and allow the space to contract to help smooth out the transient disruptions and slowly rebound without over-shooting. You want each following car to react less than the previous and have a weaker deceleration/acceleration curve. Unfortunately, I have noticed increasingly absurd feedback loops in long distance routes here in CA. As a user of conventional cruise control, I can't help but notice how frequently I now have to intervene to adjust speeds in relatively light traffic conditions. On long drives like LA-SF via I-5, these yo-yo drivers are my new nemesis. I don't know if it is due to their use of adaptive cruise controls or a more basic loss of attention or self-awareness. For example, I see packs of cars with speeds oscillating between 55-80 MPH when conditions should easily allow a steady cruise at 75 MPH.
    - lsaferite 9y ago
      Actually, if everyone perfectly tailgated out of a rolling jam, then they'd all be fine. Instead you get people that let a large enough gap open for them to accelerate faster than the car in front, then they have to brake when they reach that lead car again. This slinky effect is what causes those rolling traffic jams and why they can break them by slow-rolling in from of the jam to force everyone to stop the slinky effect.

eknkc 9y ago

Our two cars both have decent autonomous breaking tech. They did activate in actual risks a couple of times. At least once one prevented a certain crash. They act up rarely. Just some anectodes; One of them thinks I will drive into a wall when I’m approaching a 90degree turn with a wall. Does the break check from time to time. Nothing weird at high speeds for now. Other had a single break check at high speed, there was nothing in front so the sensors somehow messed up I guess. It braked for something like 100ms, at least it felt like that. Then kept driving normally. But even that was scary.

donkeyd 9y ago

My car does get triggered by lines on the street in a specific area. However, Dutch law says you're supposed to drive at a distance where you can anticipate that the car in front of you can go full stop at any time, so I'm not sure why this should cause people to do that and not the fact that they already should.

Angostura 9y ago
> However, Dutch law says you're supposed to drive at a distance where you can anticipate that the car in front of you can go full stop at any time, so I'm not sure why this should cause people to do that and not the fact that they already should. You've just explained why autonomous braking is completely unnecessary. People are perfect, never make mistakes and never assume that the car in freely-flowing traffic ahead of them won't stamp on the brakes for no apparent reason.

fantasticsid 9y ago

I’ve thought about this and and I think the best thing to do here is to relentlessly keep a long, safe distance from vehicles ahead. There are just things you can’t possibly see that the driver before you can.(a puppy/squirrel/whatever that he wants to avoid killing, you can’t possibly know). You can’t anticipate what a human will do here. You also give yourself a buffer when vehicle ahead have an emergency stop - imagine there’s a truck behind you. I guess what I’m saying is these ‘brake checks’ are welcome, even if they only serve to educate people.

cm2187 9y ago
Agree. In Europe, if you follow the recommended safety distance, you always have the time to brake if anything happens to the car in front of you. The problem is that people do not follow them.
- ProblemFactory 9y ago
  Following the recommended safety distance (2-3 seconds of travel distance if I recall correctly) is quite difficult in moderate to heavy traffic. If you leave a large enough gap with the car in front, then people will merge into that gap. If you then slow down to create a new gap - people will overtake and merge in again. You end up travelling slower than the rest of traffic, with people overtaking and merging, which creates dangers in itself.
dolzenko 9y ago
Problem is everybody else have to behave similarly, otherwise other cards just take the place of that safe distance.
- carlmr 9y ago
  It might be annoying, but even if a few cars get in between you usually don't lose much by getting a safe distance again.
  - NLips 9y ago

amelius 9y ago

> You need to consider that now random new cars may execute a "brake check" maneuver in situations where you would never anticipate a human to have done the same thing. This is to persuade you to also buy a car with new brake tech ;)

gambiting 9y ago

The car will never emergency break as long as you keep your foot on the throttle. My Merc has beeped at me couple times where it thought I was going to collide with something, but because I kept my foot down it didn't actually start breaking - the system only activates if you let go of the gas.

thrav 9y ago
The Subaru actually interprets this as you accelerating into a wall and takes over. You have to let off and then reapply for it to say, “ok, they clearly know something I don’t.”

greenhatman 9y ago

You should be expecting any driver to do an emergency stop right in front of you. I've learned the hard way not to expect anything from other drivers on the road. Make sure your following distance is such that you have enough time to react to completely oblivious driving behaviour from other drivers.

lsaferite 9y ago
> Make sure your following distance is such that you have enough time to react to completely oblivious driving behavior from other drivers. While I fully endorse this ideal, the reality of driving in high-traffic cities is that it's impossible. Every time you adjust to leave proper space, someone will come along and appropriate your safety buffer. When you slow again to allow enough space, the pattern repeats.
- icc97 9y ago
  Tragedy of the driving commons. In such situations I just drive slightly under the distance I would normally keep, but then just back off those that do barge in.
saltcured 9y ago
I didn't say we should take these braking systems off the road, but I do think drivers need to adapt to their presence. Personally, I am happy my 2017 vehicle does not have it and the ones on the market will probably be much improved by the time I consider a replacement. As others discussed throughout this thread, there are many situations where drivers violate the safe following distance rules. Aside from the lack of attention scenarios, I think many drivers take calculated risks to temporarily reduce their following distances while performing some other maneuver. They should incorporate this new idea of neurotic automatic-braking systems into this risk calculus, so they don't get caught in a situation they cannot handle. While we have a mixture of different vintage cars (and drivers!), I am afraid we will remain living in interesting times...