5 ms·

Brake lights sensitive to braking force

9 points by pedrokost 16y ago

pchristensen 16y ago
Had this discussion with a friend 13 years ago in college. Didn't know how get it to market and IIRC my friend found someone else had a patent on it.
tejaswiy 16y ago
It exists already - http://www.usautoparts.net/bmw/technology/brake_force_display.htm http://www.usautoparts.net/bmw/technology/brake_force_displa... http://www.google.com/search?q=break+force+display+bmw http://www.google.com/search?q=break+force+display+bmw
nodata 16y ago
s/sensible/sensitive/;
- pedrokost 16y ago
  Thanks for the notice. I fixed it.
pilom 16y ago
Best one I ever saw was at Carnegie Mellon. They integrated this onto a CAN bus and were in talks with Bosch. http://www.ece.cmu.edu/~ece549/spring10/team7/index.html http://www.ece.cmu.edu/~ece549/spring10/team7/index.html
sambeau 16y ago
If you are close enough behind to really tell the difference you are probably already too close.
- pedrokost 16y ago
  That's what the blue 'max deceleration' border is necessary. At least it makes it easier to see it from further away. Maximum deceleration values of a car are about up to 1G for normal cars (found the data on an unofficial forum, so it may not be right) Suppose a car in front of you brakes slowly, but for some reason you press harder the pedal, say to a deceleration of -5ms^-2 (1/2 G). Suppose a town with speed limit of 50km/h, and you and all cars drive at max speed. Suppose an initial car separation of 20m. If you do the calculations, you'll see that it will take less than 3 seconds for the back car to crash your car end. 3 secs sounds like a lot in reaction time, but the driver may be distracted, which may make him notice your braking a bit later, but not too late to apply appropriate braking and causing a car on his end.
duck 16y ago
I've seen some semi-trucks that have something like this (except it was simpler in that it was a straight light that would grow from the inside out), but do you really need them? If you just leave enough space in between you and the person in front you will never have a problem. Plus, it already is a pain to change out bulbs in some of these newer cars... I would hate for it to get harder (and more expensive).
- pedrokost 16y ago
  Many crashes are caused by the lack of such lights. And if such a system can be implemented at low cost (which it is), then why not use it? A saved life is worth more that the implementation cost. Maybe it can be at least partially be achieved with LED lights that last many years and don't break easily, if at all. Anyways I have the impression that the quality of light bulbs has increased a lot since the burst of the auto industry.
- J3L2404 16y ago
  It could be implemented by only replacing the bulbs by using a bulb that registers g-force. I could go on but I have to get to a mailbox to send these certified letters to the big automakers ;)
robinhouston 16y ago
Funny, a very similar idea was discussed here a couple of months ago, when jgrahamc mentioned it was idea 999 in one of his ideas notebooks: http://blog.jgc.org/2010/10/1000-bad-ideas.html http://blog.jgc.org/2010/10/1000-bad-ideas.html Here's the discussion: http://news.ycombinator.com/item?id=1779339 http://news.ycombinator.com/item?id=1779339
micheljansen 16y ago
I completely agree. In 2008, some students actually made this already: http://www.physorg.com/news125773212.html http://www.physorg.com/news125773212.html I wrote about it back then (in Dutch, http://micheljansen.org/blog/entry/471 http://micheljansen.org/blog/entry/471) and at that time, there were some laws preventing this from really catching on. I guess those have been changed in the mean time?
afshin 16y ago
This is a really useful idea and gives useful more fine-grained information without compromising the overall message: "I'm slowing down." Along a similar vein, I want car horns to be as loud inside a car as they are outside, to ensure they're only used for emergencies. I live in a city and car horns dramatically reduce quality of life because "no honking, $350 penalty" are never actually enforced by the police.
- hallmark 16y ago
  Re: honking. Don't travel to SE Asia; you'll be horrified.
goldenthunder 16y ago
The new Ford Mustangs have a kit you can install that does just that. I thought about this a few years back and want it so bad!
nodata 16y ago
Strong braking normally == hazard lights + brake lights on new cars. It's quicker to recognise than a graded red brake light.
osf10 16y ago
I remember reading about a similar concept by Citroen I think about 15 years ago. The brake lights would be a much pinker shade if the brakes were applied sharply.
mbyrne 16y ago
I suspect this is one of those cool ideas that in practice doesn't work so well, unfortunately. But increasing brake light intensity overall on new cars or replacement brake lamps would increase safety even though old cars might have weaker brake lights. Essentially an "Omigod!" mode.

9 points by pedrokost 16y ago

Had this discussion with a friend 13 years ago in college. Didn't know how get it to market and IIRC my friend found someone else had a patent on it.

tejaswiy 16y ago

It exists already - http://www.usautoparts.net/bmw/technology/brake_force_display.htm http://www.usautoparts.net/bmw/technology/brake_force_displa... http://www.google.com/search?q=break+force+display+bmw http://www.google.com/search?q=break+force+display+bmw

nodata 16y ago

s/sensible/sensitive/;

pedrokost 16y ago
Thanks for the notice. I fixed it.

pilom 16y ago

Best one I ever saw was at Carnegie Mellon. They integrated this onto a CAN bus and were in talks with Bosch. http://www.ece.cmu.edu/~ece549/spring10/team7/index.html http://www.ece.cmu.edu/~ece549/spring10/team7/index.html

sambeau 16y ago

If you are close enough behind to really tell the difference you are probably already too close.

pedrokost 16y ago
That's what the blue 'max deceleration' border is necessary. At least it makes it easier to see it from further away. Maximum deceleration values of a car are about up to 1G for normal cars (found the data on an unofficial forum, so it may not be right) Suppose a car in front of you brakes slowly, but for some reason you press harder the pedal, say to a deceleration of -5ms^-2 (1/2 G). Suppose a town with speed limit of 50km/h, and you and all cars drive at max speed. Suppose an initial car separation of 20m. If you do the calculations, you'll see that it will take less than 3 seconds for the back car to crash your car end. 3 secs sounds like a lot in reaction time, but the driver may be distracted, which may make him notice your braking a bit later, but not too late to apply appropriate braking and causing a car on his end.

duck 16y ago

I've seen some semi-trucks that have something like this (except it was simpler in that it was a straight light that would grow from the inside out), but do you really need them? If you just leave enough space in between you and the person in front you will never have a problem. Plus, it already is a pain to change out bulbs in some of these newer cars... I would hate for it to get harder (and more expensive).

pedrokost 16y ago
Many crashes are caused by the lack of such lights. And if such a system can be implemented at low cost (which it is), then why not use it? A saved life is worth more that the implementation cost. Maybe it can be at least partially be achieved with LED lights that last many years and don't break easily, if at all. Anyways I have the impression that the quality of light bulbs has increased a lot since the burst of the auto industry.
J3L2404 16y ago
It could be implemented by only replacing the bulbs by using a bulb that registers g-force. I could go on but I have to get to a mailbox to send these certified letters to the big automakers ;)

robinhouston 16y ago

Funny, a very similar idea was discussed here a couple of months ago, when jgrahamc mentioned it was idea 999 in one of his ideas notebooks: http://blog.jgc.org/2010/10/1000-bad-ideas.html http://blog.jgc.org/2010/10/1000-bad-ideas.html Here's the discussion: http://news.ycombinator.com/item?id=1779339 http://news.ycombinator.com/item?id=1779339

micheljansen 16y ago

I completely agree. In 2008, some students actually made this already: http://www.physorg.com/news125773212.html http://www.physorg.com/news125773212.html I wrote about it back then (in Dutch, http://micheljansen.org/blog/entry/471 http://micheljansen.org/blog/entry/471) and at that time, there were some laws preventing this from really catching on. I guess those have been changed in the mean time?

afshin 16y ago

This is a really useful idea and gives useful more fine-grained information without compromising the overall message: "I'm slowing down." Along a similar vein, I want car horns to be as loud inside a car as they are outside, to ensure they're only used for emergencies. I live in a city and car horns dramatically reduce quality of life because "no honking, $350 penalty" are never actually enforced by the police.

hallmark 16y ago
Re: honking. Don't travel to SE Asia; you'll be horrified.

goldenthunder 16y ago

The new Ford Mustangs have a kit you can install that does just that. I thought about this a few years back and want it so bad!

nodata 16y ago

Strong braking normally == hazard lights + brake lights on new cars. It's quicker to recognise than a graded red brake light.

osf10 16y ago

I remember reading about a similar concept by Citroen I think about 15 years ago. The brake lights would be a much pinker shade if the brakes were applied sharply.

mbyrne 16y ago

I suspect this is one of those cool ideas that in practice doesn't work so well, unfortunately. But increasing brake light intensity overall on new cars or replacement brake lamps would increase safety even though old cars might have weaker brake lights. Essentially an "Omigod!" mode.