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Comment by searedsteak | Hacker News Reader

Looks like maxing out acceleration solves all other problems. I guess we should require a minimum power-to-weight ratio for cars from now on.

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I've made the same observation. But I don't believe human drivers could reasonably take advantage of high acceleration, at least not as well as the simulated cars here. This is a great showcase of the usefulness of autonomous cars, though. Take humans out of the equation and traffic will flow.

The other thing that really seems to make the biggest difference (in combination with better acceleration) is following distance, which is another thing that presumably gets less important with autonomous cars because you don't really have to account for a relatively slow reaction time or poor braking.

The observation on acceleration does make me wonder whether teaching proper merging etiquette better (reach freeway speeds before you're at the merge junction) would make a significant difference if properly followed.

How do autonomous cars deal with cheap or worn tyres? Is there still a lot of allowance for braking distance?

Or weather/road conditions. Reaction time is irrelevant if you happen to be driving over an irregular/wet/oily/sandy/etc section of roadway at the moment maximum braking force is demanded.

A burnout at the beginning of every drive cycle would do wonders for calibration.

Autonomous cars still need to have adequate following distance. Without that one small problem turns into a 10+ car pileup.

Autonomous cars would be in contact with the cars ahead so it would react to car 1 braking, not number 9. IMO we will see this years before we see actual autonomous cars, no matter what fever dreams Elon Musk have.

This would actually be possible to implement with the general switch to electric cars...

What about electric trucks? I set the veh/hr to max and then when I changed truck percentage to 14% I almost immediately stopped traffic at the onramp as the trucks inevitably don't have enough space to accelerate from the meter point. Especially if one of the cars cuts the truck off.

Maxing out 'politeness', 'acceleration', and 'inflow' I could achieve nearly 7000veh/hr.

Probably impossible, since it would cause heaps of rear ending accidents. Maybe if driver assist features both prevent lane changes and optimize avg. speed.

In practice that would mean a lot more head/tail accidents, I've seen that happen plenty of times in traffic jams from over-eager drivers, sudden stops (either people trying to go too fast or not paying attention), etc.

Easier to do with self driving cars, and can probably be attained with Level 3 autonomy.

Yeah, and there would be no reason to increase acceleration -- increasing the acceleration only aids in this project because it shortens the time when the car behind the stopped car in front of it can get up to speed. If the cars are all talking to each other -- they can all start accelerating at the exact same time and rate as soon as the light turns green etc.

There's also the frequent problem of split attention when you're accelerating like that. Often you may be trying to change lanes, and checking a mirror for an opening. Even without that kind of better communication, computers are just better at tracking multiple data points at once.

That's true only when every car is a self driving car. In the interim, if only a subset of cars is running Level 3 autonomy, then including a quick acceleration into the adaptive cruise control is a good way to minimize these phantom traffic jams.

Not to mention killing a lot more non-car road users who don't have access to the same acceleration.

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