Vehicle: Car: Indicator
Rate of close indicator   (+11, -4)  [vote for, against]
Show how quickly you're closing on someone else's car.

Having nearly rear-ended three seperate people with no brake lights last night in a half hour drive, I thought something to tell me how quickly I'm coming close to someone would be nice.

Original vision was a gauge or meter or something, but I thought about it and meters are too busy to be really useful under most circumstances.

Better is a simple indicator, red means you're closing in, yellow or white means your distance is not changing, green means either you're moving away from or there is no one in range of the low power radar.
-- StarChaser, May 04 2001

Mercedes' version - "Distronic Adaptive Cruise Control"
Flash demonstration of Mercedes' version of this idea. [Acme, Oct 04 2004]

With default settings and/or user defined presets... I like it.
-- thumbwax, May 04 2001

Good one. You could have a second, rearward-pointing unit to warn you when someone is about to rear-end *you* and a buzzer for a last alert when the built-in speed/distance calculator thinks your situation is critical.
-- Dog Ed, May 04 2001

I wasn't talking about distances as such...I was talking about 'are the two cars coming closer to each other, staying the same distance, or moving apart?' Like I said, a meter would be something that's too busy on the dashboard...For me, anyway. Especially as often as one gets close to each other in traffic.
-- StarChaser, May 04 2001

I've seen automobile RADAR prototypes described. I don't know that they would give a visual readout of delta-vee, but they would typically sound an audible alarm if your relative position and velocity were sufficient to merit concern.

Apparently they never went anywhere, since I haven't heard of them since.
-- egnor, May 04 2001

I've always wanted a rate of close indicator to help me judge if an approching car in the other direction is slowing down or not. Often, when I want to make a left hand turn and there is oncoming traffic, I get stuck waiting for a car that is slowing down but not quickly enough so I can visually tell if I have time to make the left hand turn.

A simple indicator would give me a green light if I had, let's say, 7 or 8 seconds before the oncoming car, given the current rate of close, would reach my position. This, of course, should be tunable based on the acceleration potential of my vehicle.
-- quantumfluff, May 04 2001

Found this in my new issue of Popular Science: The Infiniti Q45 will have something added later this year... a laser-based adaptive cruise-control, which adjusts the vehicle's speed relative to traffic ahead. The 2002 model already has a first amongst production cars... and that is a rear-view monitor which works while you are in reverse. There is also an article on Warp Speed for you space speed demons.
-- thumbwax, May 04 2001

Egnor: They DID go somewhere...away. <grin>

I like the adaptive cruise control, something I thought of a long time ago...Wonder why the monitor only works in reverse, though...
-- StarChaser, May 05 2001

The idea is to avoid craning one's neck to see exactly what is behind one's $58,500 bucket of nuts and bolts. The camera itself is mounted in the trunk lid just to the left of the license plate. So if you're backing up with an oversize item, don't be surprised to see the sky on your 7 inch LCD screen in the car's center console.
-- thumbwax, May 05 2001

Hey, this guys coming up fast. Too fast. My god! I think we're gonna...<insert crunching metal and broken glass noises here>.
-- DrBob, May 06 2001

I understood why it was there. I meant 'Why only in reverse'. A rear-view mirror unaffected by window condensation, possibly with low-light or IR would be useful.
-- StarChaser, May 06 2001

<For anyone who doesn't want to register for the NY Times site but wants to see the links Peter keeps posting, you can use the account I just created. Username 'Halfbaker', password 'password'.>
-- StarChaser, May 12 2001

Here is a cheaper alternative. Learn to drive. If you're paying attention to what's going on around you, you won't wreck your car. I mean, if you want to drive with your eyes closed, this may help you, but i mean seriously, come on. If you can't tell whether the car in front of you is slowing down, you shouldn't be driving at all.
-- djhotsauce, May 21 2001

[djhotsauce] Here's a simple, and much cheaper alternative to the criminal justice system. Everybody stop breaking the law! Then we won't need prisons, policemen, judges, etc.

Incidentally the device described works on visual feedback, so it won't be much use to those who drive with their eyes closed.
-- synaesthesia, Apr 23 2002

There is a drawback to this type of car-automation: when people feel safer, they will go one step further and drive very close to the car in front - relying on the fact they will be warned in time.
-- spekkie, Apr 24 2002

How about an HUD superimposition that draws a pair of vertical parallel lines that are as far apart as the width of the car in front of you should be at a given speed. No, it's no rate-of-close but just a guideline for safe stopping distance.
-- bristolz, Apr 24 2002

How about an HUD superimposition that draws a pair of vertical parallel lines that are as far apart as the width of the car in front of you should be at a given speed?  No, it's no rate-of-close but just a guideline for safe stopping distance.  Doesn't involve any external device other than your own vehicle's speed.  I suppose humidity and ambient light transducer input could be used to moderate the ideal following distance.
-- bristolz, Apr 24 2002

A chevron would be better, with the apex at the calculated stopping position from your current speed. The vertical lines system means you would need to know the width of the leading vehicle.

Or less high tech - a wind powered pointer which gets higher as the speed increases. Mount it at the front of the car, allow an adjustment facility for driver eye-level and amount of shopping in the back, et voila!
-- drew, May 24 2002

Mercedes and Lexus (probably among others) have had "dynamic cruise control" for a while now. This isn't quite the same as an approach meter like you suggest, but close.. I don't know if I would want to use such a thing, unless it's displayed on a HUD like some people are suggesting. Having to take my eyes off the road to glance at a meter seems more dangerous than simply looking ahead and SEEING whether I'm approaching too fast. I trust judgment enough for that, even in the dark with cars with no tail lights.
-- awgsilyari, May 24 2002

How would you stop it falsing as you approched the corner chevron signs when leaving a motorway ? They would be stationary, so your rate of close would be high. The metal would give a good radar echo. But as you execute your turn, the alarm goes away. You'd be forever toggling the system on and off.
-- 8th of 7, Jun 13 2002

Set it to ignore anything smaller than a motorcycle. The chevron signs are tall, but tend to be small squares on sticks.

Alternatively, have it ignore anything moving toward you at exactly the speed you're moving.
-- StarChaser, Jun 14 2002

StarChaser: Yes, if you take a feed from a vehicle's speedo you can factor out statoinary objects.

So the warning goes off when your speed/range combination is getting close to the boundary of your braking performance envelope ?
-- 8th of 7, Jun 14 2002

Given that most people don't brake hard enough or react quickly enough in an emergency stop situation (particularly with ABS which makes the pedal go 'light') an audible critical alert like that would probably be the last sound you'd hear...

Chevron HUD's a nice idea, except that the system would have to incorporate some form of terrain following radar to give a reasonably accurate reading during gradient changes (as you went over the crest of a hill the stopping point could be half a mile away, or even a point somewhere in the sky).

And as for factoring out stationary objects....fog and traffic jams anyone?
-- kaiserbuk, Jun 17 2002

Any sort of distance indicator would also be beneficial to people who have vision problems, specifically people with only one eye as they have no depth of field.
-- h3lix, Feb 19 2003

Greyhound buses were beta testing an adaptibve cruise control years ago. It adjusted the bus speed based upon radar detection of the car ahead and closing speed. Not sure if they got anywhere with it, but it sounded like a good idea.

I agree about people pushing it, just like traction control and ABS, but overall I think it would make for a safer environment for everyone.
-- amuron, Feb 19 2003

I have to agree with djhotsauce... Hang-up and drive.
-- ato_de, Feb 19 2003

Yeah. Why bother inventing anything?
-- bristolz, Feb 19 2003

Hi Bris! Hi Star.. filling up..
-- po, Feb 06 2004

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