[grogenaut]

Random side thought: How do I signal in an ambiguous situation to the car on who's going first. Like Super high traffic and I want to merge in front of them or let them go first? Currently I do that with a wave. Which is super effective on a motorcycle as people almost always say "sure we can squeeze you in here" which lets me get places way faster.

[tgb]

I've read that insurance people strongly suggest to never wave: it's one of the top things that seems to occur during accidents. It's hard to distinguish from someone "waving you on" versus someone "waving to say thanks for letting me go". Trusting anyone else to check for oncoming traffic is a terrible idea. It's really easy to focus on the wave-giver and not check the rest of the traffic. And even if you are good at these, all waves are inherently involving at least 2 drivers, and you can't really count on them being any good.

I couldn't find any real information on this though. I think I picked it up from Reddit comments. Some info does suggest it's legally complicated: http://www.claimsjournal.com/news/national/2014/03/06/244965...

[bbarn]

Pre-cell phone while driving ban, my roommate turned left to a woman who waved him through, and was hit by her. She told the cop she didn't wave him through, but was gesturing to the person on the other end while talking on her phone. He was ruled at fault.

[grogenaut]

I was talking about at a 4 way stop or in 2 mph gridlock... Where is more like a construction site than traffic. I almost got smeared once by believing a blinker. Never again, I won't pull out until they are obviously in a turn.

[tgb]

Yeah there's not much else you can do at a 4 way stop if the timing is bad.

[mahyarm]

LED signs attached to the car.

[exDM69]

Yes, I absolutely do think that some kind of car-to-car communication is required for these situations.

It's not an impossible problem to solve, but I have not heard of any efforts to create a car-to-car or car-to-road communications protocol and infrastructure that would be cross-manufacturer and/or internationally approved.

In my opinion, before such a mechanism exists, autonomous cars will only work as long as the majority of cars are driven by humans. I will change my opinion when I see a demonstration of a city (or city-like test site) traffic where all or the majority of cars are autonomous.

[mcintyre1994]

There's a lot of academic work on Vehicle Adhoc Networks (VANETs) - https://en.m.wikipedia.org/wiki/Vehicular_ad_hoc_network has some sources. We discussed it a little at university in a module about mobile/sensor nerworks, it's definitely an interesting research area.