10 ms·

This isn’t really a new problem. You could engine brake your manual transmission car without touching the brakes and there’s such a thing as going uphill. I thi

This isn’t really a new problem. You could engine brake your manual transmission car without touching the brakes and there’s such a thing as going uphill. I think the bolt solution of an accelerometer gives the best indication that a car is slowing down quickly.

consp 3y ago
It's a US problem probably, everywhere manual transmission was or is a thing everybody expects cars to slow down. Also: keep enough distance, pay attention and this is never an issue.
- roomey 3y ago
  Well yes, but engine breaking is a lot weaker then regen braking can be, so there really needs to be break lights id deceleration is more than one would reasonably expect engine breaking to achieve
  - cataphract 3y ago
    Really depends on the car. There are cars with very little inertia, if you let go of the gas pedal quickly they will get quite jerky. In those, you really have to depress the clutch before completely letting go of the accelerator.
    - Enerccio 3y ago
      What kind of a car is that? I have 1.6l hyndai ix20 and I can let off gas at any time with zero issues....
- willio58 3y ago
  > keep enough distance, pay attention and this is never an issue If this was helpful, far fewer crashes would happen on roads today. People are imperfect. They're distracted, they have slow reaction times, they have poor vision, and they drive in poor weather. As the video states, regulations should definitely be altered to require car manufacturers to show brake lights no matter how deceleration occurs. It's just one additional way to prevent collisions.
  - deleted 3y ago
    [deleted]
- spookthesunset 3y ago
  > keep enough distance, pay attention and this is never an issue That isn’t how safety regulations work. Driving is a cooperative affair and giving more information about your intend to the drivers around you is a good thing. I mean if all it took was “keep distance and pay attention” why bother with turn signals? And as a side note: “self driving” cars still haven’t completely figured out the right algorithm for turn signals. I watch enough “AI Driver” on YouTube to see him call out how Tesla’s turn signaling is sometimes pretty erratic. It is probably a pretty hard problem when you think about it. Showing brake lights is much easier. Got a deceleration over a certain value? Well, show them lights!
  - mynameisvlad 3y ago
    > I mean if all it took was “keep distance and pay attention” why bother with turn signals? Have you met BMW drivers? /s You should be practicing defensive driving whenever you drive. It's what's taught nowadays and has been for a long while. You should expect others to be driving at their worst. No turn signals, broken tail lights, erratic lane change, abrupt braking or acceleration, the whole shebang. Expecting the worst is the best way to ensure your own safety on the road.
    - SuperNinKenDo 3y ago
      I laughed at the mention of BMW drivers because it's so spot on. I agree that defensive driving is always the way to go, but at a certain point you need information. TC essentially goes from 100km/h to stopped in less than 15 seconds without any obvious visual indication. That's coming to the point where there's almost no defensive driving possible and a deadly highway collision becomes more likely than not. It's the same in any situation. Always assume people will do completely insane things and prepare accordingly, but that doesn't mean we should make things more dangerous for no good reason. For all the truth that more chaotic roads make for more attentive drivers, they also still make for more accidents.
    - NikolaNovak 3y ago
      Yes. But the point is more information is good. You can be the most observant most defensively best trained driver, and more predictable information is still good. I don't understand the motivation of arguing an objectively provably demonstrably good thing, because some other thing is also good :-).
- ilyt 3y ago
  Keep enoug distance to be safe and someone will just change a lane to be in front of you, removing any safe distance you decided to keep
  - p1mrx 3y ago
    Then slow down a bit and make more space. Traffic flows better when people have room to change lanes.
    - ilyt 3y ago
      That's my complaint, if I do someone just fills that space because their lane is going 2cm/minute slower than mine
      - p1mrx 3y ago
        Then slow down a bit and make more space. There's no trophy at the end.
        ilyt 3y ago
        Which causes next car to get in front. Still no space, nor more safety, and also triggering morons to do extra maneuvers and potentially fuck up more. Do you lack ability to think about the results of the actions ?
HPsquared 3y ago
In theory you can, but 99% of the time you'd still generally use the brakes for any serious deceleration. On the other hand with one pedal driving, regen braking is used 99% of the time.
tmerc 3y ago
I've thought about putting a manual brake light switch in my manual transmission car because of this, but I'm also that guy that engine brakes more than actual brakes. 6 years of owning this car and I've never worn out a brake pad.
- OkayPhysicist 3y ago
  Wouldn't it be easier to just put some light pressure on your break pedal while you're engine breaking? My older Acura definitely lights up the break lights well before actually engaging the brakes.
  - tmerc 3y ago
    Much easier, but not as technically interesting :) And I do pedal it if I think the driver behind me is risky, though I'm not sure where the light engagement is relative to brake engagement.
  - interestica 3y ago
    That foot is on the gas pedal still in a lot of cases
- stanski 3y ago
  It's so nice to not have to ride your brakes going downhill, especially when you also have to turn at the same time. (I miss my old manual car)
  - tmerc 3y ago
    Newer manuals are really nice.. mine has hill hold, which some people hate but I enjoy. And supposedly engine braking uses no fuel.
    - function_seven 3y ago
      Unless you have an older carbureted vehicle, engine braking should use no fuel: https://en.wikipedia.org/wiki/Engine_braking#Limitations https://en.wikipedia.org/wiki/Engine_braking#Limitations Just do a decent job matching revs on the downshifts so you don't trade brake dust for clutch dust :)
Gordonjcp 3y ago
Why would you need an accelerometer when you've got perfectly good tacho pulses from the ABS rings?
- mindslight 3y ago
  AFAIK ABS modules already have accelerometers. If I had to guess it falls into the domain of the ABS module, and it's just easier to talk about it as an accelerometer, when it's really using multiple inputs (wheel speed sensors can fail). I hope whatever new regulation is intelligent enough to not consider the deceleration from coasting up a hill to be part of triggering the brake lights. Brake lights should only come on when there is deceleration beyond what you'd expect from a naturally rolling car.
  - Gordonjcp 3y ago
    One would assume it's not a difficult process to model. If the driver presses the brake, put the brake lights on. If the driver lifts off the throttle in heavy regen mode and the vehicle slows faster than <some amount> put the brake light on. If the vehicle slows faster than <some amount> with the throttle "off idle", do not put the brake light on.
Pxtl 3y ago
Going uphill isnt a problem because the car behind you is also going uphill. The point of brake lights is to warn driver's behind you they need to brake, which is why it needs to be a measure of negative force being applied by the car, not just the resultant acceleration vector.

consp 3y ago

It's a US problem probably, everywhere manual transmission was or is a thing everybody expects cars to slow down. Also: keep enough distance, pay attention and this is never an issue.

roomey 3y ago
Well yes, but engine breaking is a lot weaker then regen braking can be, so there really needs to be break lights id deceleration is more than one would reasonably expect engine breaking to achieve
- cataphract 3y ago
  Really depends on the car. There are cars with very little inertia, if you let go of the gas pedal quickly they will get quite jerky. In those, you really have to depress the clutch before completely letting go of the accelerator.
  - Enerccio 3y ago
    What kind of a car is that? I have 1.6l hyndai ix20 and I can let off gas at any time with zero issues....
willio58 3y ago
> keep enough distance, pay attention and this is never an issue If this was helpful, far fewer crashes would happen on roads today. People are imperfect. They're distracted, they have slow reaction times, they have poor vision, and they drive in poor weather. As the video states, regulations should definitely be altered to require car manufacturers to show brake lights no matter how deceleration occurs. It's just one additional way to prevent collisions.
- deleted 3y ago
  [deleted]
spookthesunset 3y ago
> keep enough distance, pay attention and this is never an issue That isn’t how safety regulations work. Driving is a cooperative affair and giving more information about your intend to the drivers around you is a good thing. I mean if all it took was “keep distance and pay attention” why bother with turn signals? And as a side note: “self driving” cars still haven’t completely figured out the right algorithm for turn signals. I watch enough “AI Driver” on YouTube to see him call out how Tesla’s turn signaling is sometimes pretty erratic. It is probably a pretty hard problem when you think about it. Showing brake lights is much easier. Got a deceleration over a certain value? Well, show them lights!
- mynameisvlad 3y ago
  > I mean if all it took was “keep distance and pay attention” why bother with turn signals? Have you met BMW drivers? /s You should be practicing defensive driving whenever you drive. It's what's taught nowadays and has been for a long while. You should expect others to be driving at their worst. No turn signals, broken tail lights, erratic lane change, abrupt braking or acceleration, the whole shebang. Expecting the worst is the best way to ensure your own safety on the road.
  - SuperNinKenDo 3y ago
    I laughed at the mention of BMW drivers because it's so spot on. I agree that defensive driving is always the way to go, but at a certain point you need information. TC essentially goes from 100km/h to stopped in less than 15 seconds without any obvious visual indication. That's coming to the point where there's almost no defensive driving possible and a deadly highway collision becomes more likely than not. It's the same in any situation. Always assume people will do completely insane things and prepare accordingly, but that doesn't mean we should make things more dangerous for no good reason. For all the truth that more chaotic roads make for more attentive drivers, they also still make for more accidents.
  - NikolaNovak 3y ago
    Yes. But the point is more information is good. You can be the most observant most defensively best trained driver, and more predictable information is still good. I don't understand the motivation of arguing an objectively provably demonstrably good thing, because some other thing is also good :-).
ilyt 3y ago
Keep enoug distance to be safe and someone will just change a lane to be in front of you, removing any safe distance you decided to keep
- p1mrx 3y ago
  Then slow down a bit and make more space. Traffic flows better when people have room to change lanes.
  - ilyt 3y ago
    That's my complaint, if I do someone just fills that space because their lane is going 2cm/minute slower than mine
    - p1mrx 3y ago
      Then slow down a bit and make more space. There's no trophy at the end.
      - ilyt 3y ago
        Which causes next car to get in front. Still no space, nor more safety, and also triggering morons to do extra maneuvers and potentially fuck up more. Do you lack ability to think about the results of the actions ?

HPsquared 3y ago

In theory you can, but 99% of the time you'd still generally use the brakes for any serious deceleration. On the other hand with one pedal driving, regen braking is used 99% of the time.

tmerc 3y ago

I've thought about putting a manual brake light switch in my manual transmission car because of this, but I'm also that guy that engine brakes more than actual brakes. 6 years of owning this car and I've never worn out a brake pad.

OkayPhysicist 3y ago
Wouldn't it be easier to just put some light pressure on your break pedal while you're engine breaking? My older Acura definitely lights up the break lights well before actually engaging the brakes.
- tmerc 3y ago
  Much easier, but not as technically interesting :) And I do pedal it if I think the driver behind me is risky, though I'm not sure where the light engagement is relative to brake engagement.
- interestica 3y ago
  That foot is on the gas pedal still in a lot of cases
stanski 3y ago
It's so nice to not have to ride your brakes going downhill, especially when you also have to turn at the same time. (I miss my old manual car)
- tmerc 3y ago
  Newer manuals are really nice.. mine has hill hold, which some people hate but I enjoy. And supposedly engine braking uses no fuel.
  - function_seven 3y ago
    Unless you have an older carbureted vehicle, engine braking should use no fuel: https://en.wikipedia.org/wiki/Engine_braking#Limitations https://en.wikipedia.org/wiki/Engine_braking#Limitations Just do a decent job matching revs on the downshifts so you don't trade brake dust for clutch dust :)

Gordonjcp 3y ago

Why would you need an accelerometer when you've got perfectly good tacho pulses from the ABS rings?

mindslight 3y ago
AFAIK ABS modules already have accelerometers. If I had to guess it falls into the domain of the ABS module, and it's just easier to talk about it as an accelerometer, when it's really using multiple inputs (wheel speed sensors can fail). I hope whatever new regulation is intelligent enough to not consider the deceleration from coasting up a hill to be part of triggering the brake lights. Brake lights should only come on when there is deceleration beyond what you'd expect from a naturally rolling car.
- Gordonjcp 3y ago
  One would assume it's not a difficult process to model. If the driver presses the brake, put the brake lights on. If the driver lifts off the throttle in heavy regen mode and the vehicle slows faster than <some amount> put the brake light on. If the vehicle slows faster than <some amount> with the throttle "off idle", do not put the brake light on.

Pxtl 3y ago

Going uphill isnt a problem because the car behind you is also going uphill. The point of brake lights is to warn driver's behind you they need to brake, which is why it needs to be a measure of negative force being applied by the car, not just the resultant acceleration vector.