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If you want traffic improvement, 1) get left lane laggards to drive properly and not slow down faster traffic 2) get everyone to be expeditious when intersection lights turn green 3) teach people not to contribute to traffic compression waves by over decelerating and then under accelerating

"Get other people to do stuff" is not usually a productive strategy ...

What you do have the power to change is your own driving.

This guy figured all that out in detail years ago ...

Actually, it was proposed by me several levels up, and there is no inherent problem in doing this if the automated vehicles maintain a safe minimal distance even when stopped. No one suggested a tightly packed convoy.

Especially in stop and go traffic, speeds are seldom likely to climb quickly, and the vehicles can space themselves according to speed automatically as the entire traffic chain speed increases. As the second car senses a speed requiring greater spacing, it simply ceases accelerating until that spacing is achieved. Then the third car, etc.

But this would only happen or be necessary somewhere above 30mph. For stoplight to stoplight, or bumper to bumper traffic, the problem is that people car constantly running up on the bumper of the person in front, instead of stopping some distance back, and maintaining that gap when stopped.

As a consequence traffic moves like a slinkie, with the back end catching up to the front and inter-vehicle gaps evaporating.
This just exacerbates the problem. A one car length gap would allow all of them to start moving at once (assuming inter vehicle telemetry).

This also applies in moving traffic. The tendency of humans to close up gaps between cars causes jams. Simply not doing that eliminates jams. But where humans don't have that kind of discipline, the autonomous vehicle might.

Its only the lane tracking part that I see as not currently practical. And you doesn't have to be in snow country to see this as a problem. Its probably un-workable with anything other than a guide wire embedded in the roadway, because as you point out simple wear and tear removes paint quickly.

Radio advertising of braking would probably also not work, just due to the nut jobs that would hack it, but it would also be very useful if they could solve that.

But I have Adaptive Cruise Control now, and I absolutely love it. My car uses a Bosch radar-based system, but there are multiple technologies already deployed. Its been around for about 10 years, and its still in its infancy, but from my experience it works very well. Works in fog too.

  Small subtle differences in the speed holding capability of vehicles running cruise control no longer drive me nuts. The car follow the one ahead at a set distance (adjustable), and its pretty reliable. The only problem with it is you may find yourself following the slowest guy on the road. But as long as there is one guy somewhere paying attention to speed limits or safe driving speeds it works great. Throw in Blind Spot monitoring and things become far less stressful.

(This is where everybody is going to jump in and say how dumb this is due to people becoming less vigilant, and lecture me on being an idiot for relying on technology to do my driving for me. I drive the same way when I have this technology or not, as I switch vehicles frequently. I would never take off on a cross country trip without Cruise Control, and having Adaptive Cruise Control is even better. Try it before you knock it. We've heard all the nay-saying we need to hear).

I find it interesting that the industry is finally adopting some of the very same techniques that Jim Beaty was so soundly criticized for back in 1998 when he posted his Traffic Wave and Jam Busting experiments. Although now they are putting it into the vehicles.

I think that the emergency brake sensor should be used as the override.

Again, it's a panic thing. People panic and try to use the (regular) brakes to stop the car. There are already ways to recover from a stuck accelerator: "Shift to neutral" and "turn ignition switch to OFF" being the most obvious. But when people are panicked because their car is accelerating out of control, they don't think clearly.

Plus, I think using the emergency brake would be a poor idea. The e-brake is typically the rear wheels only and lacks anti-lock; if it's the foot pedal variety it also typically lacks any fine control. That's a recipe for rear wheel lock-up, fish tailing, and loss of control.

It occurs to me that if you really need that extra margin while changing lanes, you're probabbly driving inappropriately for a public road.

sometimes you don't have a choice where you live and how dense the traffic is. You can either get where you want to, or you won't ever get to where you're going...

You're still probably driving inappropriately. The idea that you'll never get there because you needed to shave tens of microseconds for a lane change is... unlikely. And, ironically, people with that attitude are actually a big part of the traffic problem. If people drove properly everyone would get there faster. (See: http://trafficwaves.org/) But too many people either don't understand or don't care. Tragedy of the commons.

Sorry, it just does not happen that way in real life. You made it up.

It only takes a few people dispersed in all lanes to follow safe following rules to totally shut down that type of behavior. Even if 80% of the drivers ignore the rules, a tiny percentage of users behaving properly would shut them down.

http://trafficwaves.org/trafexp.html read it.

That argument works fine if it's just 3 cars on the road, you, the guy in front of you and the one guy who is going to slip into the safety zone. Now put 10,000 impatient fools on the same road and try to leave a safe gap without each and every driver within reach trying to fill it. The horrible truth is, either you leave the smallest possible gap you can (within _your_ safety margin) or the car in the next lane will force themselves into your safe gap.

Actually, that has been pretty much debunked as well. It simply does not happen in any meaningful way.

All it takes is a FEW cars on the road with proper inter-car gaps to totally shut down the behavior you (rationally) fear.

See this: http://trafficwaves.org/trafexp.html

Imagine a FEW cars on the road, say 5%, that had a proper distance enforcing technology. They would naturally be randomly dispersed in all lanes. These would tend to block the impatient fools. They couldn't get to you to cut in front of you (well maybe a small hand full could) because all traffic would be flowing smoothly at safe following distances, and the fools would be more or less stuck where they are.

there is no recursive slow down for the entire road.

That's only by your faulty reasoning, since you don't care about anything you see in the rearview mirror.

Try googling traffic waves to find out how much and how long your braking affects the drivers behind you.

Article also says to always obey the 3 second rule. This doesn't make sense. In heavy traffic most folks are 1/2 to one second apart. If you spread them 3 seconds apart, throughput goes down by a factor of between three and six.

Too bad, the original research is impressive and spot on.

Too bad you don't understand the difference between having enough room to maneuver at speeds and being so clumped up together that you cause standing waves of traffic.

Educate yourself: http://trafficwaves.org/trafexp.html

The fact that in heavy traffic cars are invariably clumped too close is a GIANT CLUE that it's not something that eases traffic.

Incorrect.

http://trafficwaves.org/

That site does not refute the observation that if you attempt to leave additional space, in practice people move in and fill that space, defeating the desire to use it as a buffer.

Incorrect.

http://trafficwaves.org/

See http://trafficwaves.org/trafexp.html for a model of tailgating.

People interested in traffic dynamics should check out this amateur hobbyist's blog at trafficwaves.org

I make a point of not letting them cut in front of me. I'm legally entitled to the area of space my vehicle ocupies (plus a buffer zone in front and behind sufficiently large to prevent fender benders no less). Yet these cheats are *demanding* (with screams and threatening gestures at times) that I *sacrifice my rights* for their momentary convenience.

Traffic would flow faster for everyone, including yourself, if you stopped doing that.

Optimal lane merging
Curing lane-merge traffic jams and FAQ

I make a point of not letting them cut in front of me. I'm legally entitled to the area of space my vehicle ocupies (plus a buffer zone in front and behind sufficiently large to prevent fender benders no less). Yet these cheats are *demanding* (with screams and threatening gestures at times) that I *sacrifice my rights* for their momentary convenience.

Traffic would flow faster for everyone, including yourself, if you stopped doing that.

Optimal lane merging
Curing lane-merge traffic jams and FAQ

For those people who haven't seen this before, I'd like to point you to an article about a guy who's decided that leaving a gap is a good thing:

http://trafficwaves.org/

My distilled thoughts based on what he said:

• a sudden change in traffic speed can cause a jam (not just a decrease)
• leave a large gap in front of you to swallow up jams
• drive at the average speed of the traffic, rather than the speed of the car in front of you (if the car in front is faster than this, of course)