7 ms·

Safety performance of the Waymo rider-only automated driving system [pdf]

84 points by alphabetting 4y ago

Animats 4y ago
"Every vehicle-to-vehicle contact event in the first one million miles involved one or more road rule violations or dangerous behaviors on the part of the operator of the other vehicle." That agrees with the California DMV reports. The usual problem is being rear-ended at slow speed when the autonomous vehicle detects a threat at an intersection and stops. That shows up over and over in California reports. The Arizona data has five occurrences of human drivers backing into a stationary Waymo vehicle, mostly in parking lots. That doesn't seem to be happening in California, probably because picking up people in parking lots isn't that common in San Francisco. As more human-driven vehicles get auto-braking, the rear-ending problem will probably decrease. Really bright brake lights that flash when the autonomous vehicle detects a rear-end threat might help.
- nfriedly 4y ago
  > probably because picking up people in parking lots isn't that common in San Francisco. You could probably shorten that to "probably because parking lots aren't that common in San Francisco."
- onos 4y ago
  Curious if the car weighs the risk of getting rearended when it decides to be cautious in situations like this. I have a feeling human drivers do to some degree.
  - ghaff 4y ago
    >I have a feeling human drivers do to some degree. Sure. In general, people will try not to hit the brakes any harder than they have to especially if they have the situational awareness to know someone is close (maybe too close) behind them.
    - dzdt 4y ago
      More often in my experience they will randomly tap the brakes to try to get the person behind them to back off: "brake check".
      - pclmulqdq 4y ago
        If you tend to drive too close behind people, you will see this happen a lot - people really don't like getting involved in highway pile-ups, so it's better to give you a brake check than to wait until it actually matters. However, it is very rare for people to "brake check" you unless you do that.
      - antisthenes 4y ago
        This only happens when someone is following at speed and does not maintain the proper distance. Brake checking at yield signs and stop signs isn't really a thing.
      - sbaiddn 4y ago
        You're tailgating
tropsis 4y ago
One of the reports says that the accident was caused by the other driver looking at their phone. Could potentially the sensors of the waymo detect that and warn the other driver?
- nawgz 4y ago
  "Hey guys, self-driving is a decent sprint but I think you should expand the scope to include detecting and modeling driver behavior in nearby vehicles. Add a quick study for HCI to warn drivers of their dangerous aberrant behavior and I think we might have something real here!" - tropsis, 2023
  - epicureanideal 4y ago
    “You can start the next sprint now and we’ll get the final designs to you by Thursday.” -PMs everywhere
  - mlyle 4y ago
    Lol. I think the other comment is making a suggestion that isn't quite reasonable, but maybe it's adjacent to a reasonable ask. Humans have a horn to warn other humans of unsafe behavior or conditions. We really only need to worry about warning in front of us. And we provide some warning to cars behind us in specific cases with hazard lights and brake lights. The autonomous vehicles have a better understanding of the whole state. We've already talked about warning other autonomous cars with V2V, but maybe there's something easy/sane they can do to warn human cars behind them and further increase safety.
  - jeffbee 4y ago
    Predicting the behavior of other actors on the road is a core feature of Waymo. https://waymo.com/research/identifying-driver-interactions-via-conditional-behavior-prediction/ https://waymo.com/research/identifying-driver-interactions-v...
    - nawgz 4y ago
      Of course. It's doing that by looking at the vehicle as the agent though; it has nothing to do with "the body language of this pilot suggests this vehicle will do X", it's just a predictive module because it's useless to be able to see another car if you can't predict it's going to go X units forward in the next time tick(s). Adding a layer that models human drivers to augment the prediction of this module you link would be a waste of time.
jlmcguire 4y ago
This is a breath of fresh air compared to the tesla approach which seems to be don't release any data that isn't biased. Waymo is being a responsible party here by releasing all this data even if some of the stuff around the waymo driver hitting roadway objects (like the parking lot bar or the shopping cart) is a little concerning.
- jjcon 4y ago
  What exactly is biased about the Tesla data? If anything it is far less biased imo cause it is over a massive sample of 9 billion autopilot miles as opposed to 1 million (more than 9000x the sample size) https://www.tesla.com/VehicleSafetyReport https://www.tesla.com/VehicleSafetyReport
  - kaba0 4y ago
    Teslas turn off auto-pilot as soon as it finds a complicated situation, self-filtering better statistics. This also means they drive a shitton on highways, which are just simply ”easy mode”. A better statistic report would weight a mile of city driving conditions multiple times that of a mile on the highway.
    - jjcon 4y ago
      None of that introduces bias - that is how the system is designed to work. My car has automatic cruise control that turns off in the rain. It does that FOR safety, not to boost any statistics.
      - kaba0 4y ago
        Just because it was designed like that doesn’t mean that it doesn’t introduce bias.
        jjcon 4y ago
        Bias suggests incomplete data or poorly sampled or manipulated - this is none of that. These are raw statistics on the functionality of a system - if you want to introduce bias to weight certain miles more than others that’s on you and you can do any analysis you want but Tesla is reporting what they should be - the raw statistics.
ra7 4y ago
If you don't want to read the full 30 page paper, Waymo has a blog post summarizing it: https://blog.waymo.com/2023/02/first-million-rider-only-miles-how.html https://blog.waymo.com/2023/02/first-million-rider-only-mile... It's refreshing to see Waymo continue to be transparent about their safety data. I guess it's easier to do when you have a stellar safety record.
- WkndTriathlete 4y ago
  > I guess it's easier to do when you have a stellar safety record. ... for the conditions that the Waymo vehicles operated in. Deployment of Waymo FSD across the board would seem to be a sure win in SF and Phoenix, so I hope that it gets widely adopted in those areas at minimum since I think it will save a lot of lives. There's a lot of work to be done by Waymo yet to get it to work in other areas of the country and conditions, though.
  - pb7 4y ago
    SF is not an easy locale to test in. Sure, there is no snow, but the city is narrow, dense, with a lot of challenging situations including fog, rain, and crackheads. This success seems promising.
    - gerad 4y ago
      SF is a terrible city to drive in. Narrow streets, terrible hills, a huge diversity of traffic: pedestrians, cyclists, electric scooters, buses, light rail, trains. Highly congested. Plenty of tourists driving (it’s not like NY or London where people who are visiting know not to drive).
      - nradov 4y ago
        SF doesn't seem that bad? At least not compared to Boston in the winter.
        Fatnino 4y ago
notatoad 4y ago
tl;dr: 20 collisions. 8 where another vehicle reversed into a stationary waymo vehicle. 6 where a vehicle rear-ended the waymo vehicle. 1 where a garbage truck hit a stationary waymo vehicle. 5 instances of the waymo vehicle hitting an object: - a shopping cart - a parking barrier - a construction pylon - a minibike (slid into the waymo's lane) - a plastic sign (blew over onto the waymo)
- jdlshore 4y ago
  Correction: five cases where a vehicle rear-ended the Waymo, one where the Waymo rear-ended another vehicle. In that case, the other vehicle merged into the Waymo's lane and immediately braked. Incident #7 on p11 of the report.
988747 4y ago
How does Waymo compare to human drivers when it comes to driving style? I've seen some complaints that it is annoyingly slow and indecisive sometimes, e.g. taking forever to make a left turn. Is this something Waymo also analyzes? Any hard data on that?
- alphabetting 4y ago
  I don't think there is hard data. From two rides experience in Arizona it feels eerily similar to a human driver minus it adhering the speed limit.
  - trompetenaccoun 4y ago
    And minus the times when it gets stuck and needs to be rescued by human driver either remotely or an actual Waymo guy coming over and getting in the car. Doesn't happen every time of course but it does happen.
    - tialaramex 4y ago
      Remote humans can't drive Waymo's vehicles. They can reach into the car's model of the world to correct something it misunderstood (e.g. car is confused by misplaced cone and thinks the entire carriageway is closed, actually only the left lane is closed) but they can't control the vehicle remotely at all. It's extraordinary to me how many HN readers seem to think that somehow remotely driving cars would be a good idea, but then I remember how many incredibly dumb start-up ideas get funded and it's less surprising.
      - trompetenaccoun 4y ago
        Yes, that's why I worded it as rescue and not "drive";) When the car is stuck because of an issue the software can't resolve it needs human input.
parton 4y ago
Silly question: will the Waymo AV use the horn? I see a few parking lot incidents where another driver backed into the front of a stationary Waymo AV at ~2 mph. I think a human driver might have tried honking at the other driver, on seeing a slow-motion collision about to occur.
- saalweachter 4y ago
  It would be a good feature to add, but... I've been backed into before. I didn't hit my horn. I just kept thinking, "There's no way they're going to back into me."
- minwcnt5 4y ago
  It does use the horn, but it's not clear whether it can/did in these incidents.
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anakimluke 4y ago
This reminds me of a video I watched long ago that analyzes roughly how many miles would a self-driving car need to be driven so that we can have a certain confidence that they are driving better than humans. https://www.youtube.com/watch?v=yaYER2M8dcs https://www.youtube.com/watch?v=yaYER2M8dcs
- jeffbee 4y ago
  That's a pretty superficial take. The whole thing relies on the gigantic denominator of human miles, but humans are artificially inflating their average because overwhelming majority of miles driven are extremely simple trips on limited-access highways. Waymo, by comparison, racked up its million miles driving around the SF Tenderloin, in the dark. Opposite to the claims seen elsewhere in this thread, which are omnipresent whenever the topic arises, it is in fact humans who are driving around on easy mode and self-driving car developers operate in the most difficult conditions they can find.
  - debatem1 4y ago
    > self-driving car developers operate in the most difficult conditions they can find. Ehhhhhhh. While I agree that these aren't the easiest driving environments in the world, they are certainly mild climates. If I were in the business of proving that waymo vehicles weren't ready for prime time I'd be taking them up the alcan in winter or Florida during hurricane season, not Phoenix.
  - ctchocula 4y ago
    > Waymo, by comparison, racked up its million miles driving around the SF Tenderloin, in the dark. You might be confusing them with Cruise. Waymo is driving around SF driverless 24/7 so the million miles also come from during the day, while Cruise is limited to nighttime.
AlbertCory 4y ago
It seems like a map showing the number of miles driven in each state and then in each metropolitan area within that state would be something an intern could do. Followed by a table with # miles driven in various weather conditions.
tgsovlerkhgsel 4y ago
The ones where I'd be most interested in the videos were the ones where the Waymo was stopped/slow/preparing for a turn and got hit in the back (4, 10, 12, 14). While likely the fault of the human driver, hesitant/unexpected behavior by the Waymo could have contributed to those. Three consisted of the Waymo hitting random objects - not catastrophic but clearly shows weaknesses in the self-driving: 3 (Waymo ran over a traffic cone), 17 (Waymo hit a "free swinging parking lot barrier arm"), 18 (Waymo hit a shopping cart). Ten of the accidents seem unavoidable for the Waymo and clearly someone else's fault: 1 - distracted driver rear-ends Waymo coming to a stop, with a delta-v of 20 mph. A 0.2 g deceleration could be a bit faster than normal but definitely isn't slamming the brakes, and the report mentions at one point that the other driver was using a phone. 2, 5, 6, 8, 9, 11, 13, 19 - someone hits a stationary Waymo in a parking lot or while getting out of a parking spot. [Edit: Someone pointed out that these could be preventable for the Waymo, if it knew how to use the horn. https://news.ycombinator.com/item?id=34974313 https://news.ycombinator.com/item?id=34974313] 16 - Garbage truck tried to squeeze by a stopped Waymo, didn't fit (although for this one, it is possible that a human driver would have pulled over further). Two were emergency braking situations - would be interesting to see what the reaction time was and how it compared with a human driver: 7 - someone cut off a Waymo and got rear ended 20 - Waymo hit a minibike that had crashed and tumbled into its lane, despite braking. And of course there has to be a weird one, 15 - Wind blew debris into Waymo. Overall, it seems like the report mostly avoids assigning fault, which is a good thing - in the end, how many crashes happen matters more than who was at fault. [Edit: and as the "use the horn" example shows, even when the other side is clearly at fault, improvements may be possible]
dzdt 4y ago
Sometimes it seems that Waymo is moving awfully slowly but I think they are being really smart to remain cautious and keep their safety record. One major accident like Uber had could destroy the whole program. Better to move very deliberately, and incrementally, and don't expand beyond the system's abilities.
not2b 4y ago
By comparison, collisions for human drivers are about 3.3 per million miles driven (higher for young drivers), and fatalities are about 0.01 per million miles driven. See https://www.friedmansimon.com/faqs/how-common-are-car-accidents/ https://www.friedmansimon.com/faqs/how-common-are-car-accide...

84 points by alphabetting 4y ago

"Every vehicle-to-vehicle contact event in the first one million miles involved one or more road rule violations or dangerous behaviors on the part of the operator of the other vehicle." That agrees with the California DMV reports. The usual problem is being rear-ended at slow speed when the autonomous vehicle detects a threat at an intersection and stops. That shows up over and over in California reports. The Arizona data has five occurrences of human drivers backing into a stationary Waymo vehicle, mostly in parking lots. That doesn't seem to be happening in California, probably because picking up people in parking lots isn't that common in San Francisco. As more human-driven vehicles get auto-braking, the rear-ending problem will probably decrease. Really bright brake lights that flash when the autonomous vehicle detects a rear-end threat might help.

nfriedly 4y ago
> probably because picking up people in parking lots isn't that common in San Francisco. You could probably shorten that to "probably because parking lots aren't that common in San Francisco."
onos 4y ago
Curious if the car weighs the risk of getting rearended when it decides to be cautious in situations like this. I have a feeling human drivers do to some degree.
- ghaff 4y ago
  >I have a feeling human drivers do to some degree. Sure. In general, people will try not to hit the brakes any harder than they have to especially if they have the situational awareness to know someone is close (maybe too close) behind them.
  - dzdt 4y ago
    More often in my experience they will randomly tap the brakes to try to get the person behind them to back off: "brake check".
    - pclmulqdq 4y ago
      If you tend to drive too close behind people, you will see this happen a lot - people really don't like getting involved in highway pile-ups, so it's better to give you a brake check than to wait until it actually matters. However, it is very rare for people to "brake check" you unless you do that.
    - antisthenes 4y ago
      This only happens when someone is following at speed and does not maintain the proper distance. Brake checking at yield signs and stop signs isn't really a thing.
    - sbaiddn 4y ago
      You're tailgating

tropsis 4y ago

One of the reports says that the accident was caused by the other driver looking at their phone. Could potentially the sensors of the waymo detect that and warn the other driver?

nawgz 4y ago
"Hey guys, self-driving is a decent sprint but I think you should expand the scope to include detecting and modeling driver behavior in nearby vehicles. Add a quick study for HCI to warn drivers of their dangerous aberrant behavior and I think we might have something real here!" - tropsis, 2023
- epicureanideal 4y ago
  “You can start the next sprint now and we’ll get the final designs to you by Thursday.” -PMs everywhere
- mlyle 4y ago
  Lol. I think the other comment is making a suggestion that isn't quite reasonable, but maybe it's adjacent to a reasonable ask. Humans have a horn to warn other humans of unsafe behavior or conditions. We really only need to worry about warning in front of us. And we provide some warning to cars behind us in specific cases with hazard lights and brake lights. The autonomous vehicles have a better understanding of the whole state. We've already talked about warning other autonomous cars with V2V, but maybe there's something easy/sane they can do to warn human cars behind them and further increase safety.
- jeffbee 4y ago
  Predicting the behavior of other actors on the road is a core feature of Waymo. https://waymo.com/research/identifying-driver-interactions-via-conditional-behavior-prediction/ https://waymo.com/research/identifying-driver-interactions-v...
  - nawgz 4y ago
    Of course. It's doing that by looking at the vehicle as the agent though; it has nothing to do with "the body language of this pilot suggests this vehicle will do X", it's just a predictive module because it's useless to be able to see another car if you can't predict it's going to go X units forward in the next time tick(s). Adding a layer that models human drivers to augment the prediction of this module you link would be a waste of time.

jlmcguire 4y ago

This is a breath of fresh air compared to the tesla approach which seems to be don't release any data that isn't biased. Waymo is being a responsible party here by releasing all this data even if some of the stuff around the waymo driver hitting roadway objects (like the parking lot bar or the shopping cart) is a little concerning.

jjcon 4y ago
What exactly is biased about the Tesla data? If anything it is far less biased imo cause it is over a massive sample of 9 billion autopilot miles as opposed to 1 million (more than 9000x the sample size) https://www.tesla.com/VehicleSafetyReport https://www.tesla.com/VehicleSafetyReport
- kaba0 4y ago
  Teslas turn off auto-pilot as soon as it finds a complicated situation, self-filtering better statistics. This also means they drive a shitton on highways, which are just simply ”easy mode”. A better statistic report would weight a mile of city driving conditions multiple times that of a mile on the highway.
  - jjcon 4y ago
    None of that introduces bias - that is how the system is designed to work. My car has automatic cruise control that turns off in the rain. It does that FOR safety, not to boost any statistics.
    - kaba0 4y ago
      Just because it was designed like that doesn’t mean that it doesn’t introduce bias.
      - jjcon 4y ago
        Bias suggests incomplete data or poorly sampled or manipulated - this is none of that. These are raw statistics on the functionality of a system - if you want to introduce bias to weight certain miles more than others that’s on you and you can do any analysis you want but Tesla is reporting what they should be - the raw statistics.

ra7 4y ago

If you don't want to read the full 30 page paper, Waymo has a blog post summarizing it: https://blog.waymo.com/2023/02/first-million-rider-only-miles-how.html https://blog.waymo.com/2023/02/first-million-rider-only-mile... It's refreshing to see Waymo continue to be transparent about their safety data. I guess it's easier to do when you have a stellar safety record.

WkndTriathlete 4y ago
> I guess it's easier to do when you have a stellar safety record. ... for the conditions that the Waymo vehicles operated in. Deployment of Waymo FSD across the board would seem to be a sure win in SF and Phoenix, so I hope that it gets widely adopted in those areas at minimum since I think it will save a lot of lives. There's a lot of work to be done by Waymo yet to get it to work in other areas of the country and conditions, though.
- pb7 4y ago
  SF is not an easy locale to test in. Sure, there is no snow, but the city is narrow, dense, with a lot of challenging situations including fog, rain, and crackheads. This success seems promising.
  - gerad 4y ago
    SF is a terrible city to drive in. Narrow streets, terrible hills, a huge diversity of traffic: pedestrians, cyclists, electric scooters, buses, light rail, trains. Highly congested. Plenty of tourists driving (it’s not like NY or London where people who are visiting know not to drive).
    - nradov 4y ago
      SF doesn't seem that bad? At least not compared to Boston in the winter.
      - Fatnino 4y ago

notatoad 4y ago

tl;dr: 20 collisions. 8 where another vehicle reversed into a stationary waymo vehicle. 6 where a vehicle rear-ended the waymo vehicle. 1 where a garbage truck hit a stationary waymo vehicle. 5 instances of the waymo vehicle hitting an object: - a shopping cart - a parking barrier - a construction pylon - a minibike (slid into the waymo's lane) - a plastic sign (blew over onto the waymo)

jdlshore 4y ago
Correction: five cases where a vehicle rear-ended the Waymo, one where the Waymo rear-ended another vehicle. In that case, the other vehicle merged into the Waymo's lane and immediately braked. Incident #7 on p11 of the report.

988747 4y ago

How does Waymo compare to human drivers when it comes to driving style? I've seen some complaints that it is annoyingly slow and indecisive sometimes, e.g. taking forever to make a left turn. Is this something Waymo also analyzes? Any hard data on that?

alphabetting 4y ago
I don't think there is hard data. From two rides experience in Arizona it feels eerily similar to a human driver minus it adhering the speed limit.
- trompetenaccoun 4y ago
  And minus the times when it gets stuck and needs to be rescued by human driver either remotely or an actual Waymo guy coming over and getting in the car. Doesn't happen every time of course but it does happen.
  - tialaramex 4y ago
    Remote humans can't drive Waymo's vehicles. They can reach into the car's model of the world to correct something it misunderstood (e.g. car is confused by misplaced cone and thinks the entire carriageway is closed, actually only the left lane is closed) but they can't control the vehicle remotely at all. It's extraordinary to me how many HN readers seem to think that somehow remotely driving cars would be a good idea, but then I remember how many incredibly dumb start-up ideas get funded and it's less surprising.
    - trompetenaccoun 4y ago
      Yes, that's why I worded it as rescue and not "drive";) When the car is stuck because of an issue the software can't resolve it needs human input.

parton 4y ago

Silly question: will the Waymo AV use the horn? I see a few parking lot incidents where another driver backed into the front of a stationary Waymo AV at ~2 mph. I think a human driver might have tried honking at the other driver, on seeing a slow-motion collision about to occur.

saalweachter 4y ago
It would be a good feature to add, but... I've been backed into before. I didn't hit my horn. I just kept thinking, "There's no way they're going to back into me."
minwcnt5 4y ago
It does use the horn, but it's not clear whether it can/did in these incidents.

deleted 4y ago

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deleted 4y ago

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anakimluke 4y ago

This reminds me of a video I watched long ago that analyzes roughly how many miles would a self-driving car need to be driven so that we can have a certain confidence that they are driving better than humans. https://www.youtube.com/watch?v=yaYER2M8dcs https://www.youtube.com/watch?v=yaYER2M8dcs

jeffbee 4y ago
That's a pretty superficial take. The whole thing relies on the gigantic denominator of human miles, but humans are artificially inflating their average because overwhelming majority of miles driven are extremely simple trips on limited-access highways. Waymo, by comparison, racked up its million miles driving around the SF Tenderloin, in the dark. Opposite to the claims seen elsewhere in this thread, which are omnipresent whenever the topic arises, it is in fact humans who are driving around on easy mode and self-driving car developers operate in the most difficult conditions they can find.
- debatem1 4y ago
  > self-driving car developers operate in the most difficult conditions they can find. Ehhhhhhh. While I agree that these aren't the easiest driving environments in the world, they are certainly mild climates. If I were in the business of proving that waymo vehicles weren't ready for prime time I'd be taking them up the alcan in winter or Florida during hurricane season, not Phoenix.
- ctchocula 4y ago
  > Waymo, by comparison, racked up its million miles driving around the SF Tenderloin, in the dark. You might be confusing them with Cruise. Waymo is driving around SF driverless 24/7 so the million miles also come from during the day, while Cruise is limited to nighttime.

AlbertCory 4y ago

It seems like a map showing the number of miles driven in each state and then in each metropolitan area within that state would be something an intern could do. Followed by a table with # miles driven in various weather conditions.

tgsovlerkhgsel 4y ago

The ones where I'd be most interested in the videos were the ones where the Waymo was stopped/slow/preparing for a turn and got hit in the back (4, 10, 12, 14). While likely the fault of the human driver, hesitant/unexpected behavior by the Waymo could have contributed to those. Three consisted of the Waymo hitting random objects - not catastrophic but clearly shows weaknesses in the self-driving: 3 (Waymo ran over a traffic cone), 17 (Waymo hit a "free swinging parking lot barrier arm"), 18 (Waymo hit a shopping cart). Ten of the accidents seem unavoidable for the Waymo and clearly someone else's fault: 1 - distracted driver rear-ends Waymo coming to a stop, with a delta-v of 20 mph. A 0.2 g deceleration could be a bit faster than normal but definitely isn't slamming the brakes, and the report mentions at one point that the other driver was using a phone. 2, 5, 6, 8, 9, 11, 13, 19 - someone hits a stationary Waymo in a parking lot or while getting out of a parking spot. [Edit: Someone pointed out that these could be preventable for the Waymo, if it knew how to use the horn. https://news.ycombinator.com/item?id=34974313 https://news.ycombinator.com/item?id=34974313] 16 - Garbage truck tried to squeeze by a stopped Waymo, didn't fit (although for this one, it is possible that a human driver would have pulled over further). Two were emergency braking situations - would be interesting to see what the reaction time was and how it compared with a human driver: 7 - someone cut off a Waymo and got rear ended 20 - Waymo hit a minibike that had crashed and tumbled into its lane, despite braking. And of course there has to be a weird one, 15 - Wind blew debris into Waymo. Overall, it seems like the report mostly avoids assigning fault, which is a good thing - in the end, how many crashes happen matters more than who was at fault. [Edit: and as the "use the horn" example shows, even when the other side is clearly at fault, improvements may be possible]

dzdt 4y ago

Sometimes it seems that Waymo is moving awfully slowly but I think they are being really smart to remain cautious and keep their safety record. One major accident like Uber had could destroy the whole program. Better to move very deliberately, and incrementally, and don't expand beyond the system's abilities.

not2b 4y ago

By comparison, collisions for human drivers are about 3.3 per million miles driven (higher for young drivers), and fatalities are about 0.01 per million miles driven. See https://www.friedmansimon.com/faqs/how-common-are-car-accidents/ https://www.friedmansimon.com/faqs/how-common-are-car-accide...