1925: Self-Driving Car Milestones

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Self-Driving Car Milestones
I'm working on a car capable of evaluating arbitrarily complex boolean expressions on "honk if [...]" bumper stickers and responding accordingly.
Title text: I'm working on a car capable of evaluating arbitrarily complex boolean expressions on "honk if [...]" bumper stickers and responding accordingly.


With the creation of self-driving cars, many new milestones are being found and/or solved thanks to them. Some are good, and some are downright weird. This comic lists some that have already been achieved, some that are being worked on and some that are facetious "milestones".

Milestones that have been fully or partially achieved[edit]

Automatic emergency brakes
This is another reference to how hard it can be to program human-obvious stuff (as in 1425: Tasks). A self-driving car has to be able to distinguish a danger (cliff, person on foot/cycle/etc., other cars coming the wrong way/doing weird stuff) from the side of the road, the background, the other cars, or even a light pole safely standing on the side of the road. Then the car also has to decide the optimal response, taking into account weather conditions, road type and traffic - whether to turn aside, just slow down (as danger is not imminent), or actually do the strong brake. There are big potential advantages for self-driving cars if this problem can be solved: computers don't tend to panic as much as humans, would have faster reaction times and would have more reliable judgment.
Highway lane-keeping
Sometimes, especially on highways where road delimitations might be faint or absent, or when lane markings could have faded away, a self-driving car programmed to pilot based on road markings would have issues holding to the correct side of the road. This is a bigger problem on highways than in cities, as cars move faster on highways, so the danger detection mentioned above might not manage to detect danger in time, while braking or avoiding the obstacle needs to be anticipated much more.
Already implemented in recent normal cars, this feature is important to remove the car from the road while not in use, and is sometimes considered a difficult maneuver for drivers to master, as it requires a good "feeling" of the car dimensions, as well as of distances and maneuverability of the car, and also information about surrounding barriers. The latter parameters, being easy to sense with radar and back-camera aide, are made more reliable with computers.
Full highway autonomy
The ability for a car to drive itself on a highway. As of 2023, there are plans under consideration to set highway lanes aside for self-driving cars, but this milestone would require a car to be able to operate on a highway that also has human-driven cars, as well as wildlife, pedestrians, debris and other obstacles, should they enter the highway.
First sex in a self-driving car
This is not a milestone for the cars themselves, but just the age-old practice of having sex in cars, performed in a car that happens to be self-driving. Given the nature of human sexuality, it is probable that this had already happened at the time of this comic. Self-driving also allows the act to be performed while the car is in motion. The first public documentation of this milestone was published in May of 2019, as a video featuring coitus occurring in a Tesla Model X on autopilot went viral on PornHub.
Full trips with no input from driver
The main point of self-driving cars, allowing all humans within to act as passengers. As of 2023, self-driving cars require a human to be able to take over just in case, but any such trip where the human never actually took control would qualify for this milestone. However, there could be an additional joke here that the car is driving without human input including the destination. In this case, the car itself is choosing where to go, leaving the humans helpless.

Milestones not yet reached[edit]

Full trips by empty cars
A more complete version of the above, since with no humans present, no human can take control. This could be considered fulfilled by the DARPA Grand Challenge entrants, as the challenges are racing competitions of autonomous cars with no humans on board. Possibly a reference to 1559: Driving.
Self-refueling of empty cars
This would require either: a robotic fuel station, able to refuel cars with humans inside as well; an ordinary full-service fuel station (that is, one where the station's employee performs the refueling of the car) that happens to service a self-driving car with no humans aboard (which could be arranged as a publicity stunt); a specially designed fuel station that would allow self-driving cars to refuel by docking to it (likely to require fine control of the docking procedure that would render it unsuitable for more fallible human-driven cars); or, perhaps least likely, a robotic arm attachment on the car that would allow it to use a normal self-service fuel station. Currently Tesla's robotic charging station is the closest thing to this accomplishment. It is most certainly a reference to 1559: Driving.

Facetious milestones[edit]

An empty car wandering the highways for months or years until someone notices the credit card fuel charges
Cars are expensive enough that, were one to drive itself off and wander, some effort would be made to track it down. As this would require the self-refueling milestone, local fuel stations could be alerted to look for the "rogue" car—and in any case, whatever payment method is used to pay for the fuel would be traced.
Cars that read other cars' bumper stickers before deciding whether to cut them off
Another facetious milestone, implying self-driving cars might obtain the capacity to hold and act upon opinions that might override safety and efficiency of transit. This would be generally considered undesirable[citation needed], so this seems unlikely to actually happen, except perhaps as an unintended consequence of runaway self-learning.
Autonomous engine revving at red lights
Mimicking the human practice. This is often done by human drivers who wish to draw attention to their car and then speed off as quickly as possible once the light turns green, but is regarded by most as being a nuisance. As such, this is an unlikely goal for self-driving cars to achieve.
Self-loathing cars
This would require cars to become sentient enough to understand, and have negative opinions about, themselves. Depending on one's definition, though, self-diagnostic software might qualify, as they would be running on a car's computer and could express a negative opinion about the car (albeit normally limited to the context of the car needing maintenance).
Autonomous canyon jumping
Although it seems unlikely that a navigation routine would ever decide that jumping a canyon is part of an optimal route, a car could be programmed to jump a canyon as part of a stunt or show, with no human driver (or any other human aboard) at the time of the jump. It is questionable how "autonomous" such a car would be, though. Could also be a reference to the next point, with another popular setting in the discussions mentioned below: "should a self-driving car leave the road and drive into a canyon, which will kill the driver (and passengers), or stay on the road and kill others?". Possibly a reference to when a Tesla was driven off a cliff and the driver and his passenger survived without injury. The car was not on autopilot at the time. Could also be a reference to the previous point where the car develops enough self-loathing to want to commit suicide. Or it may be a reference to certain Knight Rider episodes.
Cars capable of arguing about the trolley problem on Facebook
The Trolley problem is a well-known thought experiment in ethics, in which a person must choose between passively allowing several people to die or actively causing a single person to die. With the increasing likelihood of fully autonomous vehicles, there's been a flurry of interest in this problem, centered around what a vehicle should be programmed to do in such a case (for example, if avoiding a high-speed collision required running over a pedestrian). Munroe seems to mock this debate by arguing that the true milestone would not be when the vehicle can make such a decision, but when it can argue about it on Facebook. This may refer to the idea that humans aren't capable of agreeing on a resolution to the problem, so expecting a vehicle to resolve it would be less reasonable than expecting it to be able to debate. On the day this comic was released the Youtube channel Vsauce posted a video, The Greater Good - Mind Field S2 (Ep 1), where they tested people's reactions to the trolley problem in a fake situation where the subjects genuinely believed they were in a situation where they were choosing between saving five from an oncoming train by killing one on another track. Given such a coincidence, it is extremely likely that this milestone was added after Munroe saw the episode.
Evaluating arbitrarily complex Boolean expressions on "honk if [...]" bumper stickers and responding accordingly (title text)
As with the cut-off milestone, this implies the development of artificial intelligence unrelated to the basic functions of a car, though still imitating human drivers' behavior. This joke is a reference to a previous comic about honking and formal logic.


Upcoming and recently-achieved
Self-driving car milestones
  • Automatic emergency braking
  • Highway lane-keeping
  • Self-parking
  • Full highway autonomy
  • First sex in a self-driving car
  • Full trips with no input from driver
  • Full trips by empty cars
  • An empty car wandering the highways for months or years until someone notices the credit card fuel charges
  • Cars that read other cars' bumper stickers before deciding whether to cut them off
  • Autonomous engine revving at red lights
  • Self-loathing cars
  • Autonomous canyon jumping
  • Cars capable of arguing about the trolley problem on Facebook


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This page is, without offense to the creator, a mess. We're gonna need a table for this. 19:14, 6 December 2017 (UTC)

  • Or at least a list. I have created one, but it could use fleshing out.WingedCat (talk) 19:55, 6 December 2017 (UTC)
List is fine. You don't need a table for everything - especially if this table had only one or two columns...
none taken, it's my first time (I only wrote the first three points from a blank page) 09:08, 7 December 2017 (UTC)

I'm going to go with a [citation needed] on that "sex in a self-driving has probably already happened." Are there stats suggesting the amount of coitus per vehicle in the relevant counties?

"This a joke about Boolean satisfiability, as evaluating an arbitrarily complex bumper sticker and determining whether to honk is NP-complete." What? Determining whether to honk has nothing to do with the satisfiability problem; this is more of a joke about getting a computer to evaluate the truth of Boolean expressions that it may have no information about. Checkmate (talk) 22:07, 6 December 2017 (UTC)Checkmate

I believe the "Autonomous canyon jumping" is related to the self-loathing; a self-loathing is likely to autonomously jump off a cliff. 22:30, 6 December 2017 (UTC)

"As of 2017, self-driving s require a human to be able to take over just in case, but any such trip where the human never actually took control would qualify for this milestone." I seems like not all places require a human backup driver: https://www.theverge.com/2017/11/7/16615290/waymo-self-driving-safety-driver-chandler-autonomous 23:19, 6 December 2017 (UTC)

Time to start printing "Honk if this statement evaluates as 'do not honk!'" bumper stickers! 01:24, 7 December 2017 (UTC)

Is this related to the Vsauce Mind Field video about self-driving s and the trolley problem the literally released today, or is it just a weird coincidence? 05:13, 7 December 2017 (UTC)

The likelihood of trolley-like problems is no lower for an autonomous car than a human-driven one, since it depends on external factors. It might be true that if a significant number of the other cars on the road were replaced with self-driving ones, that would reduce the occurrence of conflicts, and therefore the likelihood and severity of these problems would be lower, but it would be lower for self-driven and human-driven cars alike. The real issue with such debates is that they tend to make a false assumption that existing human drivers are good at solving these problems, when the whole thrust of these thought experiments is to demonstrate that there are no generally accepted solutions to these problems. 09:33, 7 December 2017 (UTC)

I don't think anyone would argue that human drivers are good at handling trolley-problem situations, and we don't tend to expect humans to make good decisions under pressure. The problem is that a self-driving car would need to be programmed to make decisions in these scenarios in advance, which would involve assigning absolute values to the different options in a trolley-problem scenario. As you said, there's no generally accepted solution to these problems, so the controversy arises from deciding how self-driving cars should be programmed to handle these situations. 21:05, 7 December 2017 (UTC)
"Given the nature of human sexuality, it is possible this has already happened, but there has not been a public documentation of this milestone."

Rule 34 applies. -- 12:44, 7 December 2017 (UTC)

that part after the but is an edit from me, because the previous wording was even less plausible:
"but no one recorded the incident." - I changed that to "but there has not been a public documentation of this milestone."
because I didn't find any recording with a quick search on one of the more famous free sites for videos like that (not car videos...) Lupo (talk) 16:58, 7 December 2017 (UTC)
A simple search on pornhub (maybe I shouldn't have that in my first comment?) shows that this has already happened. TsumikiMiniwa (talk) 19:55, 22 October 2019 (UTC)
welcome to the wiki, we need experts on all kind of topics here ;) just kidding. However yes, as the explanation states, it has happened and has been documented by now (note that the other comments and the comic are from 2017). If you find a source that predates this comic, then we should mention it in the explanation. --Lupo (talk) 06:24, 23 October 2019 (UTC)

"An empty car wandering the highways" - that doesn't seem so ridiculous; a car costs what, $9000/year? That's like an EC2 instance and not even the biggest one. Sabik (talk) 13:22, 7 December 2017 (UTC)

Plus you have to factor in the potential for the cost of letting the car wander becoming cheaper than paying for a parking space, in which case it may become a deliberate choice. 13:24, 7 December 2017 (UTC)
Some stops will provide free electricity so an electric car could keep going that way. Its owner will notice it's missing but they could be sick in hospital or even dead - they may even die in the car from a medical issue if that then counts as an empty car. Why the car's journey never ends is a different question. Maybe it drives the deceased owner to work and back every day. Maybe it's searching for a parking space and charging point but cannot reach the former from the latter before it has to go back and charge again. Robert Carnegie [email protected] 16:09, 7 December 2017 (UTC)
My first thought was of a woman who had died in her house, but wasn't found for many years because her bills were all auto-paid. 14:49, 8 December 2017 (UTC)

Added a bit more to the explanation and formatted everything into a table so it's more organized. --JayRulesXKCD what's up? 13:26, 7 December 2017 (UTC)

Are there any researchers working on cars that can find a parking space? (Instead of just park in one that the human driver finds?) 14:53, 7 December 2017 (UTC)

There is a parking space app and parking payment apps. I don't know if smart cars are allowed to use these without human supervision. Robert Carnegie [email protected] 16:11, 7 December 2017 (UTC)
Tesla already has software to allow a Model S or X to park itself after dropping off human occupants at their destination. It's not yet released to owners but Tesla is testing it. ----

The first three milestones all come under the heading of recently achieved. 1.Volvo has an auto breaking system on imminent collision detection 2.lane keeping/warning systems are now relatively common. 3.Several models have automatic parking assist. 04:28, 8 December 2017 (UTC)

Perhaps commenters here are to young to remember Evel Knievel https://en.m.wikipedia.org/wiki/Evel_Knievel but I feel very confident Randall was thinking of Evel and his Snake River Canyon jump when he wrote the "Autonomous Canyon Jumping" milestone----

The table seems to miss the fact that the comic starts with things which have all been implemented in vehicles and have become commonplace, spending a lot of time talking about hypothetical problems which don't really change the fact that these things are all "done". Automatic emergency braking is available on new cars and appears to be a fairly simple collision-avoidance system. Highway lane-keeping is also definitely "solved" in the current batch of self-driving cars and is a selling point for some mainstream cars and trucks too (and the difficulties with faded lines or whatever is fairly irrelevant to the comic as a whole). Self-parking is also available in a lot of standard cars these days. "Full highway autonomy" is more or less solved now, though of course there are legal issues with it. Without doing any research I think we can all agree that "First sex..." has definitely been done by now. The first milestone that is probably in our future, now, is the "no input" line (though I can't be sure... can a user really just get into the car, give and address and do nothing else to help until it parks at its destination?). 19:16, 9 December 2017 (UTC)

The bit about first sex brings to mind "What on Earth!" What on Earth!. 07:17, 12 December 2017 (UTC)