I've checked as carefully as I (reasonably) to see if this idea has been posted before, so please bear with me.
I recently had the bad luck to be involved in a car accident as follows: I am on the freeway travelling at 70 k's, the car in fronts brake lights come on, so I go to slow down, only to realise that he has in fact STOPPED !. I slam on the brakes and stop just in time, only to be slammed from behind by someone who obviously didn't (stop in time that it).
What I'm thinking of is some sort of doppler radar, linked to a computer monitoring your own cars speed to calculate whether the car in front has in fact fully stopped, or indeed is closed to being stopped.
This system would only activate when your car was going in excess of say 60 k/hr, to avoid it sounding every 5 minutes.-- Brett-Blob, Oct 10 2007 rate of close indicator Rate_20of_20close_20indicator [po, Oct 10 2007] Mercedes-Benz has something similar to this.
You didn't even say what the computer would do with the information.-- BJS, Oct 10 2007 // You didn't even say what the computer would do with the information //
It would need to work out the speed of a vehicle in front of you by determining its relative speed less your own cars absolute speed (with reference to Einstein's theory of Special Relativity).-- Brett-Blob, Oct 10 2007 That didn't answer what I said, but I think I get it now (I didn't understand the last paragraph before), you mentioned something about a sound in the last paragraph, so I'm assuming that it will make some kind of noise.
You should clarify, and elaborate on that.
I think this is definitely a good idea, but I think that it is probably close enough to an existing technology. The technology is not, however, widely known to exist.-- BJS, Oct 10 2007 Isn't this a variant on the application of the adaptive cruise control?
It looks like your idea is merely an indicator that warns the vehicle ahead has a significantly different velocity from your own. I'd have it stab the brakes.-- elhigh, Oct 10 2007 Good idea, I want to say its currently being baked by Mercedes and Ford (Ford actually) but I havent the links to back up my claim.-- evilpenguin, Oct 10 2007 The way I would have it work would be for the system to limit your speed, so that your (calculated) stopping distance is ~90% of the distance in front of you (or maybe 4m les than the distance). Whether it involves cruise control, rev limiter and/or braking system is the complicated bit, but this way it will maintain a correct speed under all traffic conditions (traction measurements, rain sensors, etc come extra).-- neutrinos_shadow, Oct 11 2007 Thanks BJS, I was thinking that it would be a system that would be an add on a standard car and would provide an audible alarm. I don't like the idea of a computer taking over control of the car's brakes.-- Brett-Blob, Oct 11 2007 random, halfbakery