I'll start right off and say that the "Speed Sync Cruise" and the "Traffic Jam Cruise Control" Ideas (see links at above-right) have some similarities to this Idea, but certain aspects of what I want to describe were not well-presented, and so maybe this Idea might be different enough to be allowed to survive.

This device is an additional computer for a car, which connects to several other devices. One is a radar for measuring the distance to any vehicle in front; one is a connection to the car's cruise control system, including speedometer, one is a connection to the car's braking system, one is a sensor on the steering system, and one is a very low power radio transmitter at the tail of the car.

In operation, the Train-of-Cars computer first detects that the car is stopped. The assumption here is ALWAYS that the car is somewhere in a line of cars at a traffic light. The computer attempts to verify this by using the radar and listening to the transmitter of the vehicle in front. If not detected, the computer temporarily changes part of its assumption, to a mode in which it considers it is in the leading car of a lineup. The temporary assumption lasts until the car stops again, at which time another check is made for a preceding vehicle.

In the case where the car is first, the computer simply waits for the driver to accelerate, and transmits appropriate information about that acceleration through the radio in the rear. (An accurate speedometer, such as the Optical Speedometer Idea linked below, is required.) In the case where the car is not first, the computer listens for the data from the preceding car, and also passes that data on through the rear transmitter. With MUCH faster response time than a human, when the car in front accelerates, this computer also accelerates this car in perfect sync. Ditto for braking. The net effect is that with all the cars in the lineup passing data down the line, the WHOLE LINE accelerates in sync, just like a bunch of physically linked railroad cars. This bumper-to-bumper train of cars will have no significant gaps between them, and that automatically means that more will be able to get through a light than when the cars are under merely human control. Overall traffic flow is enhanced thereby.

Note that the drivers are NOT out of the loop here. They still have their own brake pedals, and if a brake is pressed (like when the traffic light turns yellow), then that car's computer immediately signals the change through the rear transmitter, allowing any/all trailing cars to slow safely, even as the leading cars start to pull away. Using the steering to pull out of the Train-of-Cars likewise signals any trailing cars to slow just a bit to ensure it happens safely. The only thing a driver in the middle of a Train-of-Cars can't do is accelerate. Only the first car can do that, and the driver of that car is NOT overruled by the computer, since the driver has a bigger picture of the traffic situation.

Note that because every driver still has control of the brakes, a Train-of-Cars situation is not dangerous when, for example, cars are leaving a parking area to get onto a road. Sure, the computer doesn't know that the car in front is not at a traffic light, but the DRIVER can see whether braking is required, or if the road is clear to allow the computer to let it accelerate with the car in front.
-- Vernon, Jun 13 2005

Optical Speedometer Optical_20Speedometer
I was about to post this Idea myself, as sibsidiary to this one, when I saw it was already here. Good show! [Vernon, Jun 13 2005]

Radar on a chip http://www.google.c...65a44::5277&e=10431
Radars are now cheap enough for every car to have one. [Vernon, Jun 13 2005]

Did not bake it http://www.halfbakery.com/user/st3f
Look around the bottom of the page [Susan, Jun 13 2005]

Baking In Progress http://news.bbc.co....hnology/8349923.stm
I wonder what they will think about certain aspects of this Idea not being patentable, since it has been in the Public Domain for more than 4 years.... [Vernon, Nov 09 2009]

More from the real-world bakery http://www.bbc.co.u...technology-12215915
Trial runs with real vehicals [Vernon, Jan 20 2011]

I've thought about this, especially when I was living in Silicon Valley. I never realized how difficult it was for people to find the pedal on the extreme right until I moved to California. [+]
-- justaguy, Jun 13 2005


Damn! Stuck my eyeliner right into my coffee. I'll call back.
-- reensure, Jun 13 2005


How does your car know if the radar signal is coming from the car in front of you or the car zooming past you in the next lane?
-- hippo, Jun 13 2005


[hippo], low power is the simplest answer to some of the questions you raise. However, the radar is at the front of your car, and is there mostly just to detect the presence of another car in front of you. For just a few feet of range, low power is indeed the answer. With respect to the transmitter at the rear of the car, I already specified low power for that. But I could also imagine the radar being used like a transmitter, requesting verification from the car in front that a received message did originate from that car. This obviously means both the front and rear of the car effectively need both a transmitter and a receiver, to ensure that all the computers in the Train-of-Cars have an accurate assessment of the line-up.
-- Vernon, Jun 13 2005


I included an idea like this in a (lousy) short story I wrote a long time ago, but it used electromagnets for a physical connection. I also imagined the lead car would do all the work: fried tranny, anyone? If the lead guy gets ticketed, shouldn't they all get ticketed? If the lead guy falls asleep, he gets majorly pancaked by all the other cars crushing him flat! I like the concept, but the execution is scary.
-- elhigh, Jun 13 2005


Folks, I just now realized that there is a side-benefit to this Idea. In auto races it is called "drafting". When your vehicle is close behind another, the air resistance you fight is lessened. Thus whenever a Train-of-Cars lines up, all the cars except the first will experience slightly better gas mileage.
-- Vernon, Jun 13 2005


So, a device which takes control of the throttle and increases the vehicle speed.

And the failure modes are?

I have yet to see a single example of a driver aid which does anything other than make up for the drivers inability to drive.
-- Twizz, Jan 20 2011


brake problems, speedometer calibration problems, sensor problems, computer problems, communication problems... This is a very problematic idea. Bun for chaos and death.
-- Voice, Jan 20 2011



random, halfbakery