Waymo robotaxis are now giving rides on freeways in LA, SF and Phoenix
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autonomous vehicles
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self-driving cars
Waymo has expanded its robotaxi service to include freeway rides in LA, SF, and Phoenix, sparking discussions about safety, scalability, and the potential impact on the ride-hailing industry.
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construction workers, delivery vehicles, traffic cones.. nothing unreasonable for it to approach with caution, brake for, and move around.
the waymo usually gets about 2 feet away from a utility truck and then sits there confused for awhile before it goes away.
it usually gets very close to these hazards before making that maneuver.
it seems like having a flashing utility strobe really messes with it and it gets extra cautious and weird around those. now, it should be respectful of emergency lights but-
i would see a problem here if it decided to do this on a freeway , five feet away from a pulled over cop or someone changing a tire.
it sure does spazz out and sit there for a long time over the emergency lights before it decides what to do
i really wish there was a third party box we could wire into strobes (or the hazard light circuit) that would universally tell an autonomous car “hey im over here somewhere you may not be expecting me , signaling for attention.”
Probably what you're witnessing is the car sitting in exception state until a human remote driver gets assigned
The real public isn't an internet comment section. Having your PR people spew statements about "well, other people have an obligation to use safe following distances" is unlikely to get you off the hook.
Of course the above needs about 6 times as many lanes as any city has. When you realize those massive freeways in Houston are what Des Moines needs you start to see how badly cars scale in cities.
Really it’s a common difficulty with utilitarianism. Tesla says “we will kill a small number of people with our self driving beta, but it is impossible to develop a self driving car without killing a few people in accidents, because cars crash, and overall the program will save a much larger number of lives than the number lost.”
And then it comes out that the true statement is “it is slightly more expensive to develop a self driving car without killing a few people in accidents” and the moral calculus tilts a bit
Maybe my memory is failing me, but I seem to remember people saying the exact opposite here on HN when Tesla first announced/showed off their "self-driving but not really self-driving" features, saying it'll be very easy to get working on the highways, but then everything else is the tricky stuff.
On highways the kinetic energy is much greater (Waymo's reaction time is superhuman, but the car can't brake any harder.) and there isn't the option to fail safe (stop in place) like their is on normal roads.
- it's easier to get to human levels of safety on freeways then on streets
- it's much harder to get to an order of magnitude better than humans on freeways than it is on streets
Freeways are significantly safer than streets when humans are driving, so "as good as humans" may be acceptable there.
That sounds outrageous if true. Very strange to acknowledge you don't actually have any specific knowledge about this thing before doing a grand claim, not just "confidently", but also label it as such.
They've been publishing some stuff around latency (https://waymo.com/search?q=latency) but I'm not finding any concrete numbers, but I'd be very surprised if it was higher than the reaction time for a human, which seems to be around 400-600ms typically.
Better technology is one of the reasons that Waymo has an active autonomous ride service and no one else does.
400-500ms is a fairly normal baseline for AV systems in my experience.
Indeed, my previously stated number was taken from here: https://news.mit.edu/2019/how-fast-humans-react-car-hazards-...
> MIT researchers have found an answer in a new study that shows humans need about 390 to 600 milliseconds to detect and react to road hazards, given only a single glance at the road — with younger drivers detecting hazards nearly twice as fast as older drivers.
But it'll be highly variable not just between individuals but state of mind, attentiveness and a whole lot of other things.
You're quite wrong. It tends to be more like 100–200 ms, which is generally significantly faster than a human's reaction.
People have lots of fears about self-driving cars, but their reaction time shouldn't be on the list.
Wait, so basically, "I don't know anything about this subject, but I'm confident regardless"?
Unlike humans they can also sense what's behind the car or other spots not directly visible to a human. They can also measure distance very precisely due to lidars (and perhaps radars too?)
A human reacts to the red light when a car breaks, without that it will take you way more time due to stereo vision to realize that a car ahead was getting closer to you.
And I am pretty sure when the car detects certain obstacles fast approaching at certain distances, or if a car ahesd of you stopped suddenly or deer jumped or w/e it breaks directly it doesn't need neural networks processing those are probably low level failsafes that are very fast to compute and definitely faster than what a human could react to
I don't really know the answers for sure here, but there's probably a gray area where humans struggle more than the Waymo.
One thing that's hard with highways is the fact that vehicles move faster, so in a tenth of a second at 65 mph, a car has moved 9.5 feet. So if say a big rock fell off a truck onto the highway, to detect it early and proactively brake or change lanes to avoid it, it would need to be detected at quite a long distance, which demands a lot from sensors (eg. how many pixels/LIDAR returns do you get at say 300+ feet on an object that's smaller than a car, and how much do you need to detect it as an obstruction).
But those also happen quite infrequently, so a vehicle that doesn't handle road debris (or deer or rare obstructions) can work with supervision and appear to work autonomously, but one that's fully autonomous can't skip those scenarios.
These are all present, but less common, on divided highways. If you're driving as many miles as Waymo, you'll encounter these situations every day.
Rare obstructions are exactly where "supervision" fails because the reaction is needed faster than the supervisor can take over.
It was a common but bad hypothesis.
"If you had asked me in 2018, when I first started working in the AV industry, I would’ve bet that driverless trucks would be the first vehicle type to achieve a million-mile driverless deployment. Aurora even pivoted their entire company to trucking in 2020, believing it to be easier than city driving.
...
Stopping in lane becomes much more dangerous with the possibility of a rear-end collision at high speed. All stopping should be planned well in advance, ideally exiting at the next ramp, or at least driving to the closest shoulder with enough room to park.
This greatly increases the scope of edge cases that need to be handled autonomously and at freeway speeds.
...
The features that make freeways simpler — controlled access, no intersections, one-way traffic — also make ‘interesting’ events more rare. This is a double-edged sword. While the simpler environment reduces the number of software features to be developed, it also increases the iteration time and cost.
During development, ‘interesting’ events are needed to train data-hungry ML models. For validation, each new software version to be qualified for driverless operation needs to encounter a minimum number of ‘interesting’ events before comparisons to a human safety level can have statistical significance. Overall, iteration becomes more expensive when it takes more vehicle-hours to collect each event.”
https://kevinchen.co/blog/autonomous-trucking-harder-than-ri...
https://enewspaper.latimes.com/infinity/article_share.aspx?g...
Note, in July of this year, Musk predicted robotaxi service for half the country by the end of 2025. It's November now and they haven't even removed the safety monitors, in any city!
> they haven't even removed safety drivers, loooosers!
Can't win either of you guys.
I think anyone back then would be totally shocked that urban and suburban driving launched to the public before freeway driving.
So then they pivoted to full time automation with a safe stop for exceptions. That's not useful to start with highway driving. There are some freeway routed mass transit lines, but for the most part people don't want to be picked up and dropped off at the freeway. In many parts of freeways, there's not a good place to stop and wait for assistance, and automated driving will need more assistance than normal driving. So it made a lot f sense to reduce scope to surface street driving.
> “Freeway driving is one of those things that’s very easy to learn, but very hard to master when we’re talking about full autonomy without a human driver as a backup, and at scale,” Waymo co-CEO Dmitri Dolgov said
and
> While many assume freeway driving is easier, it comes with its own set of challenges, principal software engineer Pierre Kreitmann said in a recent briefing. He noted that critical events happen less often on freeways, which means there are fewer opportunities to expose Waymo’s self-driving system to rare scenarios and prove how the system performs when it really matters.
Both point to freeway driving being easier to do well, but harder to be sure is being done well.
The emergency breaking system gives you a lot of room for error in the rest of the system.
Once you’re going faster than 35mph this approach no longer works. You have lots of objects on the pavement that are false positives for the emergency breaking system so you have to turn it off.
The real reason I see for not running freeways until now is that the physical operational domain of for street-level autonomous operations was not large enough to warrant validating highway driving to their current standard.
What I’ve noticed from those other systems is that a human in the loop makes the system so much more comfortable. I’ve had times where I can see the red lights ahead and the system is not yet slowing because the car immediately in front of me isn’t slowing yet. It’s unsettling when the automated system brakes at the last moment.
Because of this experience the highway has been the line in the sand for me personally. Surface streets where you’re rarely traveling more than 45 mph are far less likely to lead to catastrophic injury vs a mistake at 70 mph.
I don’t think Waymo is necessarily playing fast and loose with their tech but it will be interesting how this plays out. A few fatal accidents could be a fatal PR blow to their roll out. I’m also very curious to see how the system will handle human takeover. Stopping in the middle of a freeway is extremely dangerous. Other drivers can have a lapse in attention and getting smoked by a semi traveling 65 mph is not going to be a good day.
We had Waymo and Cruise in SF at the same time for a while and by god Cruise was shit and felt unsafe. Waymo is year ahead of Cruise and better in every manner.
https://news.gm.com/home.detail.html/Pages/topic/us/en/2025/...
> GM will integrate Cruise technology into the Super Cruise assisted driving system
Looks like it.
The political climate is VERY suspicious of autonomous vehicles, but they most serious incident I can really recall was the recent one where a car ran over a cat. You can see the reaction here: https://www.reddit.com/r/cats/comments/1omortk/the_shrine_to...
If the biggest black mark against the company is running over a cat on the street at 11:40 PM (according to Waymo, after it darted under the car), I feel pretty good.
You may be thinking of the ACC these cars offer, which is a standard feature, but different than their premium "self-driving" services they offer.
If you watch the videos more carefully, you will notice the people who speed by at 85 MPH later enter the screen again, because that is the nature of freeway traffic.
I predict that a few hundred of these on the road will measurably improve safety and decrease severe congestion by being that one sane driver that defuses stop-and-go catastrophes. In fact I think CHP should just contract with them to pace 101 in waves.
Normal human drivers tend to lift off the gas and only brake when they decide that just lifting won't do.
Don't EVs light up the brake lights when regenerative braking engages?
I've definitely observed Teslas coming to a halt, and the brake lights only kick on at the very end. I don't know how widespread the problem is, but it's very annoying.
If you're annoyed by the braking lights on a Tesla, it's because you're following too (dangerously) closely.
"Waves" are really what we would want them to prevent: https://en.wikipedia.org/wiki/Traffic_wave
The autonomous cars can prevent these waves from forming, which would get people to their destinations faster than speeding.
If you actually thought adoption would benefit us on it's own rather than seeing it a roundabout way to enforce rules that you want to see enforced without buy in from the public you'd want these cars to behave in a way that makes it easier for them to exist in typical traffic.
ive chatted up a lot of women who just feel safer with no driver and will pay more to get in the waymo. (which uber has tried to respond to by giving them a preference in driver gender.)
and some of them.. who dont really have waymo money.. really like getting on an escooter to up and get out of certain neighborhoods to do their errands or get to a job safely without being hassled on a 1-2 mile walk out of neighborhoods that rideshare drivers routinely cancel on.
now I dont take uber just because i resent how shitty they started treating me as a driver after about 7 years in with a 5.0. punishing me for stuff like prescriptions or food not being ready. i wont drive or ride with that company again. a lot of their problems stem from being left with people who are so desperate for a job theyll put up with anything that company does.
No one in LA with money is buying a sports car to "flex".
Heck, it wasn't even all that rare for it to take me 45 minutes to go 5 miles on 101 from Rengstorff Ave to Willow Rd in the Bay Area in 6pm rush hour just because of the exit.
It even once took me 2h to make it from Candlestick Park to the 101 after an NFL game.
So yeah, maybe 2 hours for a few miles isn't quite right, but I've experienced daily counterexamples to your 20mph number too.
That being said, you also have a heavy rail alternative.
Though I’ve heard people treat it differently in the US
If "we'll have too many cars on the freeway following the speed limit" ranks as a serious concern, I think we've really lost the plot.
I recently drove by a fatal accident that had just happened on the freeway. A man on the street had been ripped in half, and his body was lying on the road. I can't imagine the scene is all that unlike the 40 thousand other US road deaths that happen every year.
As a driver I'm willing to accept some minor inconvenience to improve the situation. As a rider I trust Waymo's more than human drivers.
I've lived in a couple of places where going the speed limit is a whole problem that can cascade outside of just yourself. There is an argument to be made that perhaps then the speed limit shouldn't be that low, but in driving safety is far more important than legality. It will be interesting to see how Waymo handles these realities when it gets to those areas.
I often wonder about laws that are ostensibly there to prevent dangerous actions, about whether they actually help prevent dangerous driving.
This guy analyses tailgating: https://m.youtube.com/watch?v=6n_lR09sjoU Awesome software although he seems biased (e.g. no mention of pedestrians), but he does say that tailgating is much more dangerous than speeding.
I'm interested whether cameras will start to catch dangerous drivers. I regularly seeing drivers do very dangerous things. Yet we have no easy way to train them (for those that care but are unaware), or catch them (for the antisocial that don't care).
I used to drive 20 under all the time (I achieved 57mpg once doing that) - but since this was an empty rural highway the few cars that were around saw me well in advance and moved over and passed without a problem.
There is substantial research that frustration with a slow driver in a fast lane is a significant factor in aggressive tailgating (as a way to express anger, control, or impatience) to get others to change lanes.
But perhaps research doesn't measure arseholeness?!
For selfish reasons I usually let dangerous tailgaters pass me: I want to avoid the bad outcomes from pissed off aggressive drivers.
If I'm stuck behind someone slow, I usually politely wait or politely flash lights or politely tap horn. I think Tailgating is personally dangerous as a way to signal my displeasure and I value my life highly. Polite drivers generally let one pass, and impolite drivers do whatever the fuck they want.
Regardless, it would be interesting to see stats on how risky tailgating actually is (unfortunately stats are sure to be biased by correlation versus causation).
Second, it is a widely known issue, that a slower mowing car is causing ripple-like delays far from the car itself. For example when a police car is driving inside the traffic flow. But if most of the cars are following the rules, like 95% of them, then one law abiding Waymo would fit just fine. In EU, with the deluge of speed traps and mobile patrols, most of the cars are driving under the limit, and honestly it feels fine. I'm originally from a country where +20 above was like a norm, and fast cars were +40 or more, so adjusting to EU took some effort. But now I don't even feel the need to speed, especially if it is 140km/h highway (86 m/h)
It makes less sense in an urban environment with 5 or more lanes in your direction. Vehicles will be traveling at varying speeds in all lanes, ideally with a monotonic gradient, but it just doesn't happen, and it's unlikely to.
In California, large trucks generally have a lower speed limit (however many trucks are not speed governed and do exceed the truck limit and sometimes the car limit) and lane restrictions on large highways. Waymo may do well if it tends toward staying in the lanes where trucks are allowed as those tend to flow closer to posted car speed limits. But sometimes there's left exits, and sometimes traffic flow is really poor on many right lanes because of upcoming exits. And during commute time, I think the HOV lane would be preferred; taxis are generally eligible for the HOV lane even when only the driver is present, but I don't know about self-driving with a single or no occupant.
(also it’s kind of amazing that 5 parallel lanes is considered normal in the US… I think the most I’ve ever personally seen in the UK is 4 and that’s only on very major routes, and we don’t have any exits on the wrong side of the motorway)
Not necessarily. I've seen things like the left two lanes at free flow (speed limit or above) and the right two lanes at full congestion (~ 10 mph), and the middle lane(s) somewhere in between. But then you also have sometimes where the left lane is only doing 60 for some reason, but the next two lanes are at or above the speed limits. It's a complex system.
Wrong side exits for interchanges between highways are common, depending on site details and relative flows. When there's congestion on a left exit, you then get situations where the right lanes are flowing faster than the left lanes (sometimes much faster). I don't think interchanges as left exits are necessarily awful.
Wrong side exits to surface streets have been discouraged for new construction for quite some time, but there's a fair number of "legacy exits" in some areas. They're not so bad when there's only two lanes in your direction; but when there's been highway expansion, it can get pretty hard to use. And inevitably rebuilding to current standards would causes a lot of confusion and delay, it's postponed. My exemplar of the worst left exits, the Milwaukee Zoo Interchange, was rebuilt in 2012-2022 and I can't find pictures of what it was before, but you had a sizable interchange with right and left exits to other highways, combined with several surface street exits and entrances on both sides, and I think two through lanes. It was a mess.
Plenty of people do not follow the rules about staying to the right.
My dudes, I have been driving the speed limit, even on freeways, for decades.
Nothing bad happens. Your car doesn't explode. You don't instantly create thousand-car pileups.
You get passed slightly more often than when you are speeding. You pass fewer cars. You get to your destination a few minutes later.
A car going the speed limit on the freeway is not a problem.
Until it does.
The biggest problem in car accidents is speed differential. When you are not driving the prevailing speed, your speed differential is significantly higher and the accident will be worse than average.
Motorcyclists can give you long lectures about this.
Yes: it is way more dangerous to slam into a stationary object going 80mph than it is to be rear-ended by an object going 80mph while you're going 65. Only a 15mph differential in the initial collision.
Also, it almost never happens, compared to vehicles losing control due to excessive speed.
There’s no making sense of it, people who speed will come up with infinite excuses why they are right and traffic engineers are wrong.
I’ve never been in an accident in over 40 years, I’m never late cause I leave on time and plan ahead and driving isn’t some stressful event.
I have taken at least 50 Waymo rides and have never experienced anything remotely like what you have described here.
I am not saying it never happened, just that I expect that if a bone-headed move of this magnitude was at all commonplace with Waymo, we would be hearing about it and probably with a lot more details.
Cola market share: Coke: 69% Pepsi: 27% 3rd: ???
Or public transit on a track.
I'd love to see better public transit, but transit is so bad for most of us that it would take a massive investment before there is any return, and half measures won't work. You have to go all in on transit before you can see any significant change - if you invest in the wrong network you won't know until a massive amount as been invested and there is no return (leaving open the question of if a different investment would have worked).
Did we get less dumb drivers starting in the '70's?
Per-mile-driven deaths started climbing again around 2012 in the U.S., I'd wager due to the trend towards larger vehicles causing more collateral damage.
> Google said it has tweaked its software to "more deeply understand that buses and other large vehicles are less likely to yield to us than other types of vehicles."
Maybe that got lost.
[1] https://phys.org/news/2016-03-apnewsbreak-video-google-self-...
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