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by jjmarr·5mo ago·view on hn ↗
> If cut off they absolutely will go full brake rather than perform any sort of spicy lane change or turn.

Essentially, a meat driver was waiting at a stop sign to make a turn onto the main road. I was in a Waymo driving on the main road and did not have a stop sign.

When we were 10 meters away from the intersection, the meat driver suddenly started to enter the intersection. I have no idea why.

Full brake would've hit the other car in the driver's side door at 40 km/h.

> under-playing how decent the average human is.

I got to SMFC in CSGO which means I'm in the top 3% of players in clicking on heads within 500 ms of them appearing on my screen. I have never reacted as fast as that Waymo did.

3 comments
If instant (<50ms) reaction would have lowered the speed only to 40km/h in 10m, Waymo was going too fast for the intersection IMO.

My experience is that for a human driver to react quickly in city driving conditions, style and prep are more important than reaction time: in the case you describe (entering an intersection with another car waiting on a stop sign perpendicular to your path), I'd have my foot hanging over the brake and off the gas pedal — this has helped me avoid hitting many other cars with inattentive/distracted/bad drivers, and even pedestrians running over the road or a red light on a crosswalk. When you are prepared and looking, you slam the brakes much faster!

>Waymo was going too fast for the intersection IMO.

This is literally impossible without slowing to single digit speeds for every intersections. At some point you just have to rely on the other traffic honoring signaling and signage or having some desire for self preservation.

Waymo uses new cars which probably have 100km/h (62mph) to zero stopping distance around 36m (120ft) — that's what my 2020 car quotes and tests at. As stopping distance grows quadratically, from 50km/h it would have stopped in 8m. Two lane street is usually at least 8m wide.

The claim was that after braking for 10m, it was still going at 40km/h. It'd take another 6-7m to come to a full stop. If it was a full 18m stopping distance (half the one from 100km/h), that'd mean a bit over 70km/h, so over 60km/h anyway for 16-17m.

I do not know of any country where there are intersections you can go through at 60+ km/h legally.

This does not mean that Waymo in question was going too fast, but something is off in the claim (maybe it did not react on time and really brake for 10m; maybe the collision speed was not a full 40km/h; or maybe it was going too fast...).

>I do not know of any country where there are intersections you can go through at 60+ km/h legally.

The US is dotted with "real highways" (i.e. designed as such, not a former main street that's seen a bunch of upgrades) with 50+mph speed limits and low traffic streets that tee into them with nothing more than a stop. And this isn't some middle america thing that can be dismissed as backwards flyover states. The rich coastal states have them too. Divided medians and T-junction type are fairly common. 2-way stops and cross type junctions less so in my experience but in more rural areas they're more common.

>This does not mean that Waymo in question was going too fast, but something is off in the claim (maybe it did not react on time and really brake for 10m; maybe the collision speed was not a full 40km/h; or maybe it was going too fast...).

Seems like someone pulled out from a residential road onto a main road with no f's to give and the waymo went around and OP is messing up the numbers a little. No matter how fast you're going it always feels faster from the passenger seat.

It's a huge difference between someone merging into or crossing a high speed road.

In most of Europe at least (I did not drive enough in States to remember), non-highway intercity roads have a speed limit of around 50-55mph, but where there is any merge or crossing, this is reduced to 30-35mph.

To be honest, I don't know how to convert freedom units to km/h.

I based my estimate on the Waymo going slower than other cars and the city speed limit in Toronto being 50 km/h, and I took a stab at the numbers. I think it was Beverly Blvd which the internet says has a speed limit of 35 mph = 56 kph at the time?

I was in the back seat so I couldn't judge the distance that well. I passed the other car in a second so I guessed that's how much ground I covered.

Understood: I wasn't trying to nitpick the numbers, but simply showing that you were likely crediting Waymo a tad too much for what it has done.

Human drivers correct each others' mistakes every single day, and we don't hear about them because... well, nothing has happened. The argument could be made that Waymos will make fewer mistakes, so fewer evasive maneuvers will be needed, but it's great to hear that Waymo's performance is coming closer to bringing good human driver capability with faster reaction time enabled by tech.

I appreciate you converting to SI units, but I am ok with you keeping them as-is too: either side can do the conversion to whatever they need, and HN is very much a mixed audience.

Pulling out randomly, I see it all the time. I beat the computer by a) anticipating; and b) assuming other drivers are idiots who don't see me. I don't have to calculate trajectories and whatnot, people aren't computers, and they can do some things better than a computer can, especially a solely-reactive one.
To be fair, we are not provided with the sensors to swerve safely. If we had some sort of 360 constant recording in the car (on screen?) it would be safer for humans to swerve. Instead we have to move our head, which is cheaper but lacks info. That's why we now have rear cameras
We have rear cameras because people DONT move their head. And because regulations have made cars way taller than they need to be, meaning there is a big blind spot close to the ground
I mean, even in low cars you cannot see a small enough kid walking behind your car. That's why you back slowly. Back when I just got my driver license, there is a big lesson many drivers go through (in Italy) which is you back off a parking and there is an obstacle that's so low that cannot be see through the back window and it's small enough that cannot be seen through the mirror. You hit it and if you followed the "go slow part" you only damaged the paint.

So I'm not opposing the ideas of rear cameras, but I'm totally against tall cars, because you cannot see kids IN FRONT either now.