I recently lived in Oxford where they have a few self-driving car trials (notably Oxbotica) that essentially just went round and round the station because of how awkward some of the junctions were.

If we want to really test self-driving cars, introduce them to Milton Keynes 'Magic Roundabout'

https://www.google.com/search?q=milton+keynes+magic+roundabo...

Apparently Brits hate the Magic Roundabout, but it seems so shiny.. just the idea of a roundabout of roundabouts where the inner flow of traffic is reversed is really pretty. I'm sure it's one of those things that looks great in traffic flow simulations but falls apart when panicked drivers are trying to deal with each other and the unconventional traffic patterns.

I don't think most people in the UK who express an opinion on it have ever actually used it.

I used to live round the corner from the magic roundabout. It's actually fine. The best analogy I have for it is juggling, if I concentrate too much and overthink it I drop the balls. If you over-think the magic roundabout it can seem intimidating, but when you're actually there it makes much more sense and you just go with the flow. You're not dealing with the whole system in one go, most people just take it one roundabout at a time.

One of the reasons it seems to work is that people take it easy, everyone is paying attention to what they are doing, and most people take it at a sensible speed.

What I don't understand is what advantage it has over just a single big roundabout. A single car may be able to save a few seconds by going around in a different direction, but I can't picture any actual throughput advantage.

Needless complexity is all I see in it.

I'm not sure the Magic Roundabout would pose any problem for any sort of automated driving. It's basically just a nested roundabout- where you essentially have to give the right-of-way to traffic already on the roundabout.

If you can navigate a roundabout, you can navigate the magic roundabout - you just apply the same rules.

If anything, this is the sort of thing an automated system would excel over humans at - where the automation won't get confused by an uncommon application of a familiar ruleset.

100% Phoenix is basically a big grid with a relatively flat elevation. SF is quite contrary to that organization with elevation changes, more dense traffic and irregular roads being common.

Re>> "that can give experienced human drivers a nervous breakdown"

A couple of years ago I took a wrong turn and got lost in the Long Beach harbor - and had neither GPS nor phone. Holy Cow man.... holy cow... (admittedly, low quality comment)

The streets of pre-pandemic San Francisco were an unmitigated clusterfuck, arguably the worst in the nation at its 2019 peak. I imagine it's much easier these days for an autonomous vehicle.

> arguably the worst in the nation at its 2019 peak

Not even close - I've lived in the DC metro, Boston, and LA and all three are certainly worse than SF, and I think that is also backed up by evidence.

Other than reduced volume has San Francisco done something to unfuck its clusters?

Absolutely not.

Same with Coimbra, Portugal. Would love to see a Waymo car trying to navigate those old intricate roads.

Just checked it out on google. What a beautiful place.

My scepticism around SD cars in places like that and Bath is not even the roads themselves, but the traffic.

The are quite a lot of roads around me that are quite narrow and frequently drop to single lanes. I feel like any self-drive system will need to develop quite an advanced theory of mind to perform the weird silent negotiation that happens when I'm driving a long, with three cars behind me, and come face-to-face with a bus coming the other way, and somehow we have to either backup en-masse, or perform the squeeze dance as we edge past each other with inches to spair.

I wonder if Waymo can use street mirrors.

I hadn't even considered those. It would be interesting to see how confused Telsa FSD got when confronted by something like that.

Yeah SF is very messy configuration wise and is more "european" in that way.

Partly due to challenges with the landscape right?

It's a thumb shaped peninsula seven miles across with a 922' peak in the middle. Market St runs diagonally through downtown separating two grid systems, the south side of which is offset by about 40 degrees. Columbus St runs diagonally in the opposite direction through Little Italy and China Town, itself a maze of one way streets, ancient buildings, triangular parks and steep hills. The whole thing is cut up by trolly tracks, makeshift bike lanes, and more pedestrians per square foot than most places in the US. Be prepared for your two-lane road to suddenly turn into a one-way street running towards you, seven way intersections, pedestrian traffic that never stops, and lane markers that completely disappear in the rain. On top of everything, intersections are only ever labeled in one corner, but never the same corner, and at least half of the stop signs are behind trees that should have been trimmed five years ago. Also it seems like 10% of drivers are drunk or stoned, and there's a moving van blocking 60% of the road everywhere, all the time.