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The Annoying Thing About Self-Driving Cars: They Obey the Speed Limit

75 points by pwg 14y ago

ricardobeat 14y ago
Stupidest story title of the week.
SlipperySlope 14y ago
I for one, welcome law-abiding driverless cars. Speed limits are set for a public benefit, and its a sort of tragedy of the commons why speeding by humans is the norm.
- CountHackulus 14y ago
  Sadly, a lot of speed limits aren't set according to government standard 85th percentile, and local governments are easily swayed to lower speed limits just with a few letters from citizens, no study needed. That's when you get things like 6 lane divided roads with a 50km/h speed limit. Just excruciatingly slow.
  - repsilat 14y ago
    > 6 lane divided roads with a 50km/h speed limit. It's important to note that there isn't an obvious relationship between traffic volume and traffic speed. If you model traffic separation as a constant two seconds (front-to-front) your traffic flow is 1800 vehicles per hour at all speeds. Of course, your average person cares more about how close the back of the car in front of them is, so flow rates at very low speeds are lower than at high speeds. At higher speeds you get other problems, though - traffic gets "patchy" as some people get a little nervous, as people drive at different speeds and so on. You probably get the most people per hour through a lane of traffic at around 60km/h. Everyone's travelling at about the same separation and about the same speed, and they're all tailgating the guy in front of them trying to make him go a little faster. The speed leaves enough breathing room for everyone to drive consistently, which is supposed to be the big benefit of these self-driving cars. Of course, these lower limits seem to increase travel times in a very obvious way, and the congestion relief they provide is pretty abstract. It's understandable that people aren't entirely convinced.
- civilian 14y ago
  The major danger on highways is difference in speed between cars ("variable traffic"), it's much safer to go with the flow of traffic. Absolute speed has little to do with it. Additionally, speed limits are set for the benefit of police (increasing ticket costs) and for the benefit of politicians who can now say they are "making roads safer". Case in point: the Autobahn http://autos.aol.com/article/driving-the-autobahn/ http://autos.aol.com/article/driving-the-autobahn/ (but I am also still welcoming driverless cars! I'm okay getting places slower if it means I can read or study.)
  - SlipperySlope 14y ago
    The debate over the exact causes of traffic accidents, fatalities, with regard to speed limits, intoxication, texting, etc. can be simplified by just agreeing that the largest general cause is driver inattention or error, without drilling down any deeper. Driverless cars are fully attentive, and should have a lower error rate than normal / tired / drunk / distracted / angry / frustrated humans. This I welcome.
  - MrFoof 14y ago
    Well, there are a lot of other reasons for the speed limits as well. Lack of sufficient climbing lanes on most of the original interstate system. Poorly designed junctions, including merges into the high-speed lanes Inadequate road thickness (autobahn is 55-75cm, US is 28cm), initial quality, drainage capability and maintenance. Inadequate driver training. Lack of enforcement for failing to bear right (though the US is doing this more now) and other minor moving violations that disrupt traffic flow. The US interstate system would need considerable re-engineering, more funding to keep up with the required maintenance, and both tougher licensing requirements and stricter enforcement of minor moving violations that increase risk. It's a huge cost, that doesn't provide proportionate benefit in all parts of the country, and a questionable ROI. Trust me, I'd love higher speed limits, but I realize the giant mountain of money and effort that would be required to make it happen.
- SwellJoe 14y ago
  Speed limits will, inevitably, climb as safety increases based on self-driving cars and more predictable traffic conditions. Self-driving cars will not just obey the law, they'll also keep a safe distance to the car in front, based on speed and time-to-stop (among correcting many other common mistakes drivers make that lead to more accidents, the faster they drive).
  - philwelch 14y ago
    And my state, for one, will have to find another source of revenue. It's politically impossible to raise taxes, or even keep taxes at the same level, in Washington.
    - SlipperySlope 14y ago
      I suppose that new use taxes will be created for driverless cars. Especially driverless and eventually passenger-free commercial vehicles. The state can take a share from the resulting productivity increase. As a thought experiment, imagine that Walmart is given the opportunity to buy more expensive driverless long haul trucks, that are still much cheaper to operate because no driver is needed. Walmart would be willing to pay a use tax for each mile driven as long as the total business case made sense for the life of the new vehicles.
      - SwellJoe 14y ago
        I hope new taxes don't happen. That would set back the move to driverless cars...every year we don't make the switch is a year in which tens of thousands of people die in car accidents that didn't have to happen. I suspect this is one of those areas where we're only thinking of the negative consequences, and not the positives. What if you no longer need highway patrol officers to enforce speed limits and traffic laws? Or maybe you need a tenth as many on the road? What if the number of times emergency responders are needed dropped precipitously because of fewer accidents? Emergency room visits are the only socialized medicine in the US (and horribly inefficient socialized medicine at that), so reducing them will have a huge impact on road-related expenditures borne by all of us. What if we can begin to phase out signage and signals because the cars know where we're going and know when to stop and start? It will be decades before all cars are self-driving, but roads and lanes could be designated self-driving only, and those lanes could be free of extraneous signals and signs. What if we can reduce number of miles traveled by optimizing routes, thus reducing damage to roads (subtly, but for big trucks, the differences could add up faster)? Taxing self-driving vehicles more would be an impediment to a great good, so I hope that doesn't happen.
noonespecial 14y ago
Its not really important what speed driverless cars actually settle on. What matters is that they are consistent. The most dangerous thing about human drivers is that they are erratic. I would not be at all surprised in the coming world of robo-cars to find that humans who still wanted to drive themselves will need special licensing and training, much like pilots of today, if nothing more than to learn to be predictable.
- hyperbovine 14y ago
  Actually it is very important from a fuel economy perspective. Air resistance is quadratic in velocity, so a car that gets 35mpg at 65mph will get, say, 20mpg going 85. On the other hand, the possibility of convoy driving (http://phys.org/news/2011-05-drivers.html http://phys.org/news/2011-05-drivers.html) means you might be able to have your cake and eat it too: rapid travel with little efficiency loss from wind resistance.
  - mc32 14y ago
    I'm not sure I'd feel safe about convoy driving unless there were some kind of way to manage emergencies (like a tire blowout, engine problem, deer) which under normal circumstances isn't very dangerous because you have a second or two to manoeuver. But in a close convoy system, there is little room for error and even an automated system may be unable to compensate for the emergency in a timely fashion thus resulting in a chain reaction crash --the kind we see in foggy conditions with human drivers.
    - DeepDuh 14y ago
      I'm sure that convoy driving is another 15-20 years in the future from the point where self-driving takes off. However it's not like those dangers you mention cannot be managed. Self-driving cars already require a wide array of sensors - together in a convoy you get such an amount of data that the computers should be able to get out of hairy situation at any point.
    - SlipperySlope 14y ago
anusinha 14y ago
This isn't very smart. Most delays and jams and other various issues drivers deal with are a result of human error. Suppose a driver on a highway slows down because {they see something interesting, their kid acts up, life happens}. This makes the car immediately behind them slow down. And the car behind that slows down. It's been shown that this forms a wave that propagates backwards at 12 mph or so. The fact is, this delay is caused by a human mistake/issue. In a world in which every car drives "optimally", or at least without many of the human error mistakes that currently are made, many traffic jams will be a thing of the past. Many issues will cease to exist any any issues that do exist will be ameliorated and fixed by a machine that can do it better than most humans (or at least, the average joe) can. Perhaps one will be able to drive at the speed limit the entire distance from source to sink if the traffic grid is integrated into the network. The transition to the post-driver road, however, will be difficult.
- SwellJoe 14y ago
  There was a fun blog post several years ago, which has stuck with me ever since, and I think about it every time I'm stuck in a traffic jam. It was a one-man experiment in "fixing" traffic jams, by willfully slowing to the point where he no longer had to stop/start and could maintain a steady speed. He found that traffic behind him would "unkink", making the drive for everyone behind him a bit more pleasant/safe/consistent. He also found that many drivers would become angry at him, because he was going slower than the cars around him...but the cars around him were speeding up only to have to stop soon after to wait for traffic. Many people are, frankly, too stupid to be in control of a couple thousand pounds of rolling death...but, it'll be a challenge to get people to give up that control. Hopefully, the ability to read, play games, watch TV, etc. while being driven to work will be sufficient to make people willing to let their smart cars take over the roads. As you note, traffic jams will become a thing of the past in most cases; self-driving cars can also factor in traffic data, weather information, etc. in ways that a human driver probably can't easily/effectively do, making them safer and more efficient in a lot of other regards.
  - ghshephard 14y ago
    s/Many people/Most people/
mediocregopher 14y ago
Once (begin assumption here) autonomous cars become the norm I don't think this will be a problem. The reason speed limits exist at all is because we don't want people who are not physically capable of driving at that speed (poor eyesight, bad reflexes, etc....) to try, so we set the limit at a level where we think everyone should be reasonably ok in that situation. But if all cars are run by computers, we can raise speed limits considerably, since reaction time, sleeplessness, stupidity, etc... are all non-factors anymore. The only problem is whether or not your car can actually go as fast as everyone else, but for that we can set up fast and slow lanes similar to the somewhat unofficial way things go on the highway now (faster the closer to the leftmost lane you are).
- grecy 14y ago
  > The reason speed limits exist at all is because we don't want people who are not physically capable of driving at that speed to try Is that the reason we have speed limits? I've always thought it's more like we don't want to deal with the consequences of something going wrong when there is too much energy involved. i.e. blow a tire, or hit a patch of gravel at 60mph and see what happens. Now try it at 160mph.
ChuckMcM 14y ago
While they may obey the speed limit, they will also drive in the right lane so it's OK. What is annoying are people blocking passing lanes which results in aggressive drivers making less than good decisions about maneuvering around the blockage.
Brajeshwar 14y ago
This will be an issue as long as we have more human drivers and few self-driving cars. In future when there are more or all of them are self-driving ones, there won't be any need for limits - speed or otherwise. The cars can know the position, speed of each other and figure out how fast they can go to reach their destinations. Perhaps you can pay a subscription so you can always drive at a higher speed than most normal people or buy tickets to drive fast for that day when you need most.
mc32 14y ago
Once we get to the point where all cars on highways are automation capable, if not outright enabled, there should be the option to have speed dictated by road conditions so that, under optimal conditions, the system could adjust speed up, and adjust speed down as conditions worsen. That is, allow speed to be variable and dependent on conditions on the road (at that particular section). Or, they could rate different lanes at different speeds, or a combo allowing people to tell the system where to merge into. There is the complication of less capable cars --so that maybe bunches of cars (those part of a wave of traffic) would have to submit to the safety levels of the least safe vehicle. (Let's say a bunch of high performance sports cars and an economical car which isn't designed for hugging the road nor has grippy tires; or, throw in a cargo truck). Maybe the rightmost lane could be reserved for non autonomous vehicles like classics and holdouts (people afraid of automation/driverlessness). Given that speeding tickets would be rare, the state could impose fees based on a combination of emissions and also road wear (tonnage, for example) to offset lost revenue.
w1ntermute 14y ago
Hopefully within the next 30 years or so, we will gradually phase out driver's licenses. Much like how smoking was ubiquitous in the 50s & 60s, but as we as a society came to realize its grave dangers, it gradually became illegal in many public places. The idea that we allow almost anyone 16 or older to control several thousand pounds of metal that can travel at high speeds really is quite absurd when you think about it. There are more than 30,000 deaths every year due to car accidents, and hundreds of thousands more injuries. It's amazing how screwed up our society's priorities are. That's ten 9/11's worth of deaths every year from car accidents. By the time the wars in Afghanistan and Iraq have ended, we'll have spent around $4 trillion on them altogether[0]. If even 1/100th of that had been redirected to research on self-driving car technology, we might have already saved tens of thousands of lives. 0: http://www.reuters.com/article/2011/06/29/us-usa-war-idUSTRE75S25320110629 http://www.reuters.com/article/2011/06/29/us-usa-war-idUSTRE...
- sliverstorm 14y ago
  It's amazing how screwed up our society's priorities are. Consider it rationally. Driving is costly, but it engenders an entire host of benefits & pleasures I don't think you're even considering. I'm not saying I'm happy driving is dangerous, but saying "Driving is dangerous, and yet we do it? WTF?" is ridiculous.
  - w1ntermute 14y ago
    > Consider it rationally. Driving is costly, but it engenders an entire host of benefits & pleasures I don't think you're even considering. I am considering it entirely rationally. I believe that we should be investing more money into research that could save 30,000 lives every year. Never did I suggest in my initial post that human driving should be banned before self-driving cars are capable of replacing humans in this capacity. If done correctly, self-driving cars will have all the benefits of current automobiles, and then some. As for the pleasures of driving - that's what a whole lot of people said about cigarettes, but look where we are now. And don't be silly - no one's personal "pleasures" override the safety of other people's lives.
ivankirigin 14y ago
But you won't notice the speed because you'll be working in your car, not minding the road.
- dllthomas 14y ago
  Not when you can't yet afford an autonomous car and are cursing at the guy cruising along at 50 ahead of you, getting work done comfortably while you're gripping the wheel in frustration...
  - ivankirigin 14y ago
    But you'll be in a driverless uber :)
abruzzi 14y ago
I'll be fine with that as long as lane splitting is legal on my non-autonomous motorcycle. Since lane splitting is legal in CA, I wonder how well google's vehicles deal with other drivers that split lanes?
- dkokelley 14y ago
  I've seen demonstrations where the autonomous car recognizes bicyclists and adjusts the travel path to avoid the "obstacle". I imagine with a motorcycle the autonomous car should always see it coming up behind it and could be programmed to give it some room as it gets close.
Ianworld 14y ago
I believe Google has publicly said a few things that are slightly contrary to this. Their vehicles are allowed to exceed the speed limit by 5%-10% in order to keep pace with a car in front of them. They do this because currently there are few things as reliable in terms of road information as another car being driven by a human. So the code makes an exception basically saying that its better to break the speed limit in order to be able to do the lazy thing and follow another car. Having worked on an autonomous car and competed in the Urban Challenge I can attest to the safety of these vehicles. They truly can navigate obstacles that are withing 2-3 inches of the car reliably and confidently. The other interesting thing is that highways are in many ways one of the easiest types of road to drive on. Highway driving while fast, is very structured. There are relatively few rules to follow and they are rarely broken. For this reason I believe highways will be the initial realm of autonomous vehicles and that they will be allowed to drive at higher speeds(perhaps under the guise of human control of the speed in order to shift the blame to a human party.)
anacrolix 14y ago
What's the point of a speed limit if there's no element of human error anymore? That's just suggesting that the existing speed limit is arbitrarily set in the first place.
z92 14y ago
> and honking does no good, because robots do not care if you honk at them. That sounds like a larger problem and even harder to solve. How do you teach a robot to react to honking, like how humans can?
- qbrass 14y ago
  Some microphones and a robot arm that can flip the bird.
- georgemcbay 14y ago
  Why should the robot care about the honking? It should already have way more data via sensor input than the human doing the honking has long before the honk ever occurs. Even ignoring that, I don't think I've ever seen a situation in which I think a horn actually helped in a near-accident situation. It tends to just be the thing someone honks in anger after the immediate danger is already avoided. IME (as someone who has never been in an accident but has seen quite a few near misses and accidents on SoCal freeways) usually once the horn comes into play it is either too late and the accident occurs anyway or the horn is honked after the fact as a "fuck you" to the other person.
  - viraptor 14y ago
    Actually it should care about signals. Maybe not honking, but there are cases like emergency vehicles that you react to. I'm not sure what's the standard reaction in other parts, but in the UK when you hear / see an ambulance or a police car behind you, you stop on the side of the road. Sometimes partly on the pedestrian area. Would the self driving car do the same to let the emergency vehicle pass it? Unfortunately that's unlikely.
niketdesai 14y ago
It's a disappointment this writer is covering this topic. Self-driving cars can be great because of the shear impact on utility for vehicles and safety implications. I'm quite excited about the advent of self-driving cars and the underling operating systems that will make them amazing for humans. I do believe there is room for both types of driving. It's possible our freeways will be segmented such that automated cars can go in certain lanes (perhaps even barrier protected) while the remaining traffic stays in other lanes / roads. Traffic, or more specifically congestion, is primarily caused by excess cars on any edge (road) in which it simply takes N+1 cars to cause. Inconsistent driving patterns cause effective waves of inconsistency down the pipe exacerbating the situation (stop and go traffic actually makes congestion even worse). Thinking about the overall network at a higher level makes all of this even more exciting. Consider the scenario in which N cars are on an edge with capacity N. If your car was about to enter the road you would basically contribute to traffic. This cost, C, is then felt across N+1 (don't forget to include yourself!) people at a minimum which is C*(N+1) minutes of human time that is lost. If our cars, and ourselves, were better informed you might take an alternate and sub-optimal route that taxes you an extra T minutes but the overall network of time is optimized. Perhaps you'll even get a reward for it. And perhaps the reward is simply allowing all the people currently on the road a faster commute home so they can be with their loved ones. Beyond that, as people have mentioned here already, the faster we can go and caravanning (which can be done safely by allowing cars to attach to one another in train format) improves overall throughput (and make traffic less likely). Finally if we think about traffic, it's really just load and it needs to be distributed better across all possible routes and time. We have commute hours, but one thing to think about is that with a self-driving car I can leave to LA at 12AM and get there at 6AM while sleeping in the back of the car. Self-driving cars will increase utility on vehicles, but also on time for travel routes ideally. This will spread the load (since humans generally have some biological clock they operate by) to utilize the 24 hours a day we have a little bit better. And if your car can't speed I guess we should invest in really good alarm clocks and reminders :)
kayoone 14y ago
Remember that most of the world hasnt even adopted automatic transmission because people like to have full control over their cars and that technology is decades old.
danmaz74 14y ago
If streets will prove themselves much safer with self-driving cars, speed limits could be safely increased.
someone13 14y ago
One thing that always worried me about self-driving cars - what about an emergency? For example, hypothetically, if my wife was giving birth and I needed to rush to the hospital, would I have to poke along at 50km/h and hope to get there on time? There are times when it's perfectly justified to break the speed limit (other examples: outrunning natural disasters, going to visit a dying relative, and so on).
- miahi 14y ago
  You call an ambulance, that has an overclocked version of the self-driving chip :). I don't see the self-driving car as a completely different car than a normal one - maybe more like an expensive option (with all the sensors, data and stuff it will be expensive) for a normal car, that can give you back the control when you want it.
- Inufu 14y ago
  I'm pretty sure you could root your car to make it go faster, just as you can root your phone to overclock it ;)
- finnw 14y ago
  No it is not perfectly justified to break the speed limit if you are going to visit a dying relative. That's ridiculous. Think about it. If I was going to visit a dying relative (who you have never met) would you be happy for me to drive at 100mph along the street where you live?
- bluesnowmonkey 14y ago
  A self-driving car would be handy in situations where you are alone and injured, with the capacity to get to your car but not to drive safely. Severe illness, power tool accident, bear attack on a camping trip. You just get in your car and say, "Take me to the emergency room." It would actually be faster than an ambulance that had to make a round trip. Also, pretty much the last person we (as a society) want speeding is a tired, stressed, freaking-out, distracted, soon-to-be-husband.
latimer 14y ago
If self-driving cars keep their much safer track record when they start being actually used by the public, maybe they can adapt the carpool lane to be a self-driving car lane which has a higher speed limit?
rocky1138 14y ago
This will no longer be a problem if all cars are self-driving. Then, they can just up the limit incrementally. Possibly even to something much faster than a human could do manually.
stewie2 14y ago
I think the first usage of self-driving cars is for public transportation. With this technologies, crowed areas could have more self-driving buses. or use it to replace long distance truck drivers.
asher_ 14y ago
Road speed limits are based on standards that take in to account the environmental circumstances of the road - straightness, visibility, etc - as well as having a huge amount of safety buffer built in to account for human reaction time. If self driving cars become ubiquitous, there is no longer a reason to have this buffer built in. Perhaps the whole idea of posted speed limits will become obsolete if the software determines the maximum speed in the moment for a certain risk tolerance.
pasbesoin 14y ago
Part of the problem is that communities keep lowering the speed limits below recommendations and even the guidelines of law. My father, who has a background in urban planning, is fond of, or frustrated enough to point this out. A street that, per our state's code and regulation, should be 45 mph, gets dropped to 40, then to 35. Nothing significant has changed with its facing development and use. But the community, or of some excess of caution or some orthogonal desire for control, keeps ratcheting it down. In other spots, they start putting up stop signs at every block. They aren't really warranted, but in a variety of "think of the children" attitude, perhaps combined with a twist on NIMBY (Not In My Back-Yard) attitude, the through-street needs to "be somewhere else". Until there no longer is a through-street. So fine, have these cars obey the speed limits. But then set reasonable limits, ones that are evidence-based and not politicized.

75 points by pwg 14y ago

Stupidest story title of the week.

I for one, welcome law-abiding driverless cars. Speed limits are set for a public benefit, and its a sort of tragedy of the commons why speeding by humans is the norm.

CountHackulus 14y ago
Sadly, a lot of speed limits aren't set according to government standard 85th percentile, and local governments are easily swayed to lower speed limits just with a few letters from citizens, no study needed. That's when you get things like 6 lane divided roads with a 50km/h speed limit. Just excruciatingly slow.
- repsilat 14y ago
  > 6 lane divided roads with a 50km/h speed limit. It's important to note that there isn't an obvious relationship between traffic volume and traffic speed. If you model traffic separation as a constant two seconds (front-to-front) your traffic flow is 1800 vehicles per hour at all speeds. Of course, your average person cares more about how close the back of the car in front of them is, so flow rates at very low speeds are lower than at high speeds. At higher speeds you get other problems, though - traffic gets "patchy" as some people get a little nervous, as people drive at different speeds and so on. You probably get the most people per hour through a lane of traffic at around 60km/h. Everyone's travelling at about the same separation and about the same speed, and they're all tailgating the guy in front of them trying to make him go a little faster. The speed leaves enough breathing room for everyone to drive consistently, which is supposed to be the big benefit of these self-driving cars. Of course, these lower limits seem to increase travel times in a very obvious way, and the congestion relief they provide is pretty abstract. It's understandable that people aren't entirely convinced.
civilian 14y ago
The major danger on highways is difference in speed between cars ("variable traffic"), it's much safer to go with the flow of traffic. Absolute speed has little to do with it. Additionally, speed limits are set for the benefit of police (increasing ticket costs) and for the benefit of politicians who can now say they are "making roads safer". Case in point: the Autobahn http://autos.aol.com/article/driving-the-autobahn/ http://autos.aol.com/article/driving-the-autobahn/ (but I am also still welcoming driverless cars! I'm okay getting places slower if it means I can read or study.)
- SlipperySlope 14y ago
  The debate over the exact causes of traffic accidents, fatalities, with regard to speed limits, intoxication, texting, etc. can be simplified by just agreeing that the largest general cause is driver inattention or error, without drilling down any deeper. Driverless cars are fully attentive, and should have a lower error rate than normal / tired / drunk / distracted / angry / frustrated humans. This I welcome.
- MrFoof 14y ago
  Well, there are a lot of other reasons for the speed limits as well. Lack of sufficient climbing lanes on most of the original interstate system. Poorly designed junctions, including merges into the high-speed lanes Inadequate road thickness (autobahn is 55-75cm, US is 28cm), initial quality, drainage capability and maintenance. Inadequate driver training. Lack of enforcement for failing to bear right (though the US is doing this more now) and other minor moving violations that disrupt traffic flow. The US interstate system would need considerable re-engineering, more funding to keep up with the required maintenance, and both tougher licensing requirements and stricter enforcement of minor moving violations that increase risk. It's a huge cost, that doesn't provide proportionate benefit in all parts of the country, and a questionable ROI. Trust me, I'd love higher speed limits, but I realize the giant mountain of money and effort that would be required to make it happen.
SwellJoe 14y ago
Speed limits will, inevitably, climb as safety increases based on self-driving cars and more predictable traffic conditions. Self-driving cars will not just obey the law, they'll also keep a safe distance to the car in front, based on speed and time-to-stop (among correcting many other common mistakes drivers make that lead to more accidents, the faster they drive).
- philwelch 14y ago
  And my state, for one, will have to find another source of revenue. It's politically impossible to raise taxes, or even keep taxes at the same level, in Washington.
  - SlipperySlope 14y ago
    I suppose that new use taxes will be created for driverless cars. Especially driverless and eventually passenger-free commercial vehicles. The state can take a share from the resulting productivity increase. As a thought experiment, imagine that Walmart is given the opportunity to buy more expensive driverless long haul trucks, that are still much cheaper to operate because no driver is needed. Walmart would be willing to pay a use tax for each mile driven as long as the total business case made sense for the life of the new vehicles.
    - SwellJoe 14y ago
      I hope new taxes don't happen. That would set back the move to driverless cars...every year we don't make the switch is a year in which tens of thousands of people die in car accidents that didn't have to happen. I suspect this is one of those areas where we're only thinking of the negative consequences, and not the positives. What if you no longer need highway patrol officers to enforce speed limits and traffic laws? Or maybe you need a tenth as many on the road? What if the number of times emergency responders are needed dropped precipitously because of fewer accidents? Emergency room visits are the only socialized medicine in the US (and horribly inefficient socialized medicine at that), so reducing them will have a huge impact on road-related expenditures borne by all of us. What if we can begin to phase out signage and signals because the cars know where we're going and know when to stop and start? It will be decades before all cars are self-driving, but roads and lanes could be designated self-driving only, and those lanes could be free of extraneous signals and signs. What if we can reduce number of miles traveled by optimizing routes, thus reducing damage to roads (subtly, but for big trucks, the differences could add up faster)? Taxing self-driving vehicles more would be an impediment to a great good, so I hope that doesn't happen.

noonespecial 14y ago

Its not really important what speed driverless cars actually settle on. What matters is that they are consistent. The most dangerous thing about human drivers is that they are erratic. I would not be at all surprised in the coming world of robo-cars to find that humans who still wanted to drive themselves will need special licensing and training, much like pilots of today, if nothing more than to learn to be predictable.

hyperbovine 14y ago
Actually it is very important from a fuel economy perspective. Air resistance is quadratic in velocity, so a car that gets 35mpg at 65mph will get, say, 20mpg going 85. On the other hand, the possibility of convoy driving (http://phys.org/news/2011-05-drivers.html http://phys.org/news/2011-05-drivers.html) means you might be able to have your cake and eat it too: rapid travel with little efficiency loss from wind resistance.
- mc32 14y ago
  I'm not sure I'd feel safe about convoy driving unless there were some kind of way to manage emergencies (like a tire blowout, engine problem, deer) which under normal circumstances isn't very dangerous because you have a second or two to manoeuver. But in a close convoy system, there is little room for error and even an automated system may be unable to compensate for the emergency in a timely fashion thus resulting in a chain reaction crash --the kind we see in foggy conditions with human drivers.
  - DeepDuh 14y ago
    I'm sure that convoy driving is another 15-20 years in the future from the point where self-driving takes off. However it's not like those dangers you mention cannot be managed. Self-driving cars already require a wide array of sensors - together in a convoy you get such an amount of data that the computers should be able to get out of hairy situation at any point.
  - SlipperySlope 14y ago

anusinha 14y ago

This isn't very smart. Most delays and jams and other various issues drivers deal with are a result of human error. Suppose a driver on a highway slows down because {they see something interesting, their kid acts up, life happens}. This makes the car immediately behind them slow down. And the car behind that slows down. It's been shown that this forms a wave that propagates backwards at 12 mph or so. The fact is, this delay is caused by a human mistake/issue. In a world in which every car drives "optimally", or at least without many of the human error mistakes that currently are made, many traffic jams will be a thing of the past. Many issues will cease to exist any any issues that do exist will be ameliorated and fixed by a machine that can do it better than most humans (or at least, the average joe) can. Perhaps one will be able to drive at the speed limit the entire distance from source to sink if the traffic grid is integrated into the network. The transition to the post-driver road, however, will be difficult.

SwellJoe 14y ago
There was a fun blog post several years ago, which has stuck with me ever since, and I think about it every time I'm stuck in a traffic jam. It was a one-man experiment in "fixing" traffic jams, by willfully slowing to the point where he no longer had to stop/start and could maintain a steady speed. He found that traffic behind him would "unkink", making the drive for everyone behind him a bit more pleasant/safe/consistent. He also found that many drivers would become angry at him, because he was going slower than the cars around him...but the cars around him were speeding up only to have to stop soon after to wait for traffic. Many people are, frankly, too stupid to be in control of a couple thousand pounds of rolling death...but, it'll be a challenge to get people to give up that control. Hopefully, the ability to read, play games, watch TV, etc. while being driven to work will be sufficient to make people willing to let their smart cars take over the roads. As you note, traffic jams will become a thing of the past in most cases; self-driving cars can also factor in traffic data, weather information, etc. in ways that a human driver probably can't easily/effectively do, making them safer and more efficient in a lot of other regards.
- ghshephard 14y ago
  s/Many people/Most people/

mediocregopher 14y ago

Once (begin assumption here) autonomous cars become the norm I don't think this will be a problem. The reason speed limits exist at all is because we don't want people who are not physically capable of driving at that speed (poor eyesight, bad reflexes, etc....) to try, so we set the limit at a level where we think everyone should be reasonably ok in that situation. But if all cars are run by computers, we can raise speed limits considerably, since reaction time, sleeplessness, stupidity, etc... are all non-factors anymore. The only problem is whether or not your car can actually go as fast as everyone else, but for that we can set up fast and slow lanes similar to the somewhat unofficial way things go on the highway now (faster the closer to the leftmost lane you are).

grecy 14y ago
> The reason speed limits exist at all is because we don't want people who are not physically capable of driving at that speed to try Is that the reason we have speed limits? I've always thought it's more like we don't want to deal with the consequences of something going wrong when there is too much energy involved. i.e. blow a tire, or hit a patch of gravel at 60mph and see what happens. Now try it at 160mph.

ChuckMcM 14y ago

While they may obey the speed limit, they will also drive in the right lane so it's OK. What is annoying are people blocking passing lanes which results in aggressive drivers making less than good decisions about maneuvering around the blockage.

Brajeshwar 14y ago

This will be an issue as long as we have more human drivers and few self-driving cars. In future when there are more or all of them are self-driving ones, there won't be any need for limits - speed or otherwise. The cars can know the position, speed of each other and figure out how fast they can go to reach their destinations. Perhaps you can pay a subscription so you can always drive at a higher speed than most normal people or buy tickets to drive fast for that day when you need most.

mc32 14y ago

Once we get to the point where all cars on highways are automation capable, if not outright enabled, there should be the option to have speed dictated by road conditions so that, under optimal conditions, the system could adjust speed up, and adjust speed down as conditions worsen. That is, allow speed to be variable and dependent on conditions on the road (at that particular section). Or, they could rate different lanes at different speeds, or a combo allowing people to tell the system where to merge into. There is the complication of less capable cars --so that maybe bunches of cars (those part of a wave of traffic) would have to submit to the safety levels of the least safe vehicle. (Let's say a bunch of high performance sports cars and an economical car which isn't designed for hugging the road nor has grippy tires; or, throw in a cargo truck). Maybe the rightmost lane could be reserved for non autonomous vehicles like classics and holdouts (people afraid of automation/driverlessness). Given that speeding tickets would be rare, the state could impose fees based on a combination of emissions and also road wear (tonnage, for example) to offset lost revenue.

w1ntermute 14y ago

Hopefully within the next 30 years or so, we will gradually phase out driver's licenses. Much like how smoking was ubiquitous in the 50s & 60s, but as we as a society came to realize its grave dangers, it gradually became illegal in many public places. The idea that we allow almost anyone 16 or older to control several thousand pounds of metal that can travel at high speeds really is quite absurd when you think about it. There are more than 30,000 deaths every year due to car accidents, and hundreds of thousands more injuries. It's amazing how screwed up our society's priorities are. That's ten 9/11's worth of deaths every year from car accidents. By the time the wars in Afghanistan and Iraq have ended, we'll have spent around $4 trillion on them altogether[0]. If even 1/100th of that had been redirected to research on self-driving car technology, we might have already saved tens of thousands of lives. 0: http://www.reuters.com/article/2011/06/29/us-usa-war-idUSTRE75S25320110629 http://www.reuters.com/article/2011/06/29/us-usa-war-idUSTRE...

sliverstorm 14y ago
It's amazing how screwed up our society's priorities are. Consider it rationally. Driving is costly, but it engenders an entire host of benefits & pleasures I don't think you're even considering. I'm not saying I'm happy driving is dangerous, but saying "Driving is dangerous, and yet we do it? WTF?" is ridiculous.
- w1ntermute 14y ago
  > Consider it rationally. Driving is costly, but it engenders an entire host of benefits & pleasures I don't think you're even considering. I am considering it entirely rationally. I believe that we should be investing more money into research that could save 30,000 lives every year. Never did I suggest in my initial post that human driving should be banned before self-driving cars are capable of replacing humans in this capacity. If done correctly, self-driving cars will have all the benefits of current automobiles, and then some. As for the pleasures of driving - that's what a whole lot of people said about cigarettes, but look where we are now. And don't be silly - no one's personal "pleasures" override the safety of other people's lives.

ivankirigin 14y ago

But you won't notice the speed because you'll be working in your car, not minding the road.

dllthomas 14y ago
Not when you can't yet afford an autonomous car and are cursing at the guy cruising along at 50 ahead of you, getting work done comfortably while you're gripping the wheel in frustration...
- ivankirigin 14y ago
  But you'll be in a driverless uber :)

abruzzi 14y ago

I'll be fine with that as long as lane splitting is legal on my non-autonomous motorcycle. Since lane splitting is legal in CA, I wonder how well google's vehicles deal with other drivers that split lanes?

dkokelley 14y ago
I've seen demonstrations where the autonomous car recognizes bicyclists and adjusts the travel path to avoid the "obstacle". I imagine with a motorcycle the autonomous car should always see it coming up behind it and could be programmed to give it some room as it gets close.

Ianworld 14y ago

I believe Google has publicly said a few things that are slightly contrary to this. Their vehicles are allowed to exceed the speed limit by 5%-10% in order to keep pace with a car in front of them. They do this because currently there are few things as reliable in terms of road information as another car being driven by a human. So the code makes an exception basically saying that its better to break the speed limit in order to be able to do the lazy thing and follow another car. Having worked on an autonomous car and competed in the Urban Challenge I can attest to the safety of these vehicles. They truly can navigate obstacles that are withing 2-3 inches of the car reliably and confidently. The other interesting thing is that highways are in many ways one of the easiest types of road to drive on. Highway driving while fast, is very structured. There are relatively few rules to follow and they are rarely broken. For this reason I believe highways will be the initial realm of autonomous vehicles and that they will be allowed to drive at higher speeds(perhaps under the guise of human control of the speed in order to shift the blame to a human party.)

anacrolix 14y ago

What's the point of a speed limit if there's no element of human error anymore? That's just suggesting that the existing speed limit is arbitrarily set in the first place.

z92 14y ago

> and honking does no good, because robots do not care if you honk at them. That sounds like a larger problem and even harder to solve. How do you teach a robot to react to honking, like how humans can?

qbrass 14y ago
Some microphones and a robot arm that can flip the bird.
georgemcbay 14y ago
Why should the robot care about the honking? It should already have way more data via sensor input than the human doing the honking has long before the honk ever occurs. Even ignoring that, I don't think I've ever seen a situation in which I think a horn actually helped in a near-accident situation. It tends to just be the thing someone honks in anger after the immediate danger is already avoided. IME (as someone who has never been in an accident but has seen quite a few near misses and accidents on SoCal freeways) usually once the horn comes into play it is either too late and the accident occurs anyway or the horn is honked after the fact as a "fuck you" to the other person.
- viraptor 14y ago
  Actually it should care about signals. Maybe not honking, but there are cases like emergency vehicles that you react to. I'm not sure what's the standard reaction in other parts, but in the UK when you hear / see an ambulance or a police car behind you, you stop on the side of the road. Sometimes partly on the pedestrian area. Would the self driving car do the same to let the emergency vehicle pass it? Unfortunately that's unlikely.

niketdesai 14y ago

It's a disappointment this writer is covering this topic. Self-driving cars can be great because of the shear impact on utility for vehicles and safety implications. I'm quite excited about the advent of self-driving cars and the underling operating systems that will make them amazing for humans. I do believe there is room for both types of driving. It's possible our freeways will be segmented such that automated cars can go in certain lanes (perhaps even barrier protected) while the remaining traffic stays in other lanes / roads. Traffic, or more specifically congestion, is primarily caused by excess cars on any edge (road) in which it simply takes N+1 cars to cause. Inconsistent driving patterns cause effective waves of inconsistency down the pipe exacerbating the situation (stop and go traffic actually makes congestion even worse). Thinking about the overall network at a higher level makes all of this even more exciting. Consider the scenario in which N cars are on an edge with capacity N. If your car was about to enter the road you would basically contribute to traffic. This cost, C, is then felt across N+1 (don't forget to include yourself!) people at a minimum which is C*(N+1) minutes of human time that is lost. If our cars, and ourselves, were better informed you might take an alternate and sub-optimal route that taxes you an extra T minutes but the overall network of time is optimized. Perhaps you'll even get a reward for it. And perhaps the reward is simply allowing all the people currently on the road a faster commute home so they can be with their loved ones. Beyond that, as people have mentioned here already, the faster we can go and caravanning (which can be done safely by allowing cars to attach to one another in train format) improves overall throughput (and make traffic less likely). Finally if we think about traffic, it's really just load and it needs to be distributed better across all possible routes and time. We have commute hours, but one thing to think about is that with a self-driving car I can leave to LA at 12AM and get there at 6AM while sleeping in the back of the car. Self-driving cars will increase utility on vehicles, but also on time for travel routes ideally. This will spread the load (since humans generally have some biological clock they operate by) to utilize the 24 hours a day we have a little bit better. And if your car can't speed I guess we should invest in really good alarm clocks and reminders :)

kayoone 14y ago

Remember that most of the world hasnt even adopted automatic transmission because people like to have full control over their cars and that technology is decades old.

danmaz74 14y ago

If streets will prove themselves much safer with self-driving cars, speed limits could be safely increased.

someone13 14y ago

One thing that always worried me about self-driving cars - what about an emergency? For example, hypothetically, if my wife was giving birth and I needed to rush to the hospital, would I have to poke along at 50km/h and hope to get there on time? There are times when it's perfectly justified to break the speed limit (other examples: outrunning natural disasters, going to visit a dying relative, and so on).

miahi 14y ago
You call an ambulance, that has an overclocked version of the self-driving chip :). I don't see the self-driving car as a completely different car than a normal one - maybe more like an expensive option (with all the sensors, data and stuff it will be expensive) for a normal car, that can give you back the control when you want it.
Inufu 14y ago
I'm pretty sure you could root your car to make it go faster, just as you can root your phone to overclock it ;)
finnw 14y ago
No it is not perfectly justified to break the speed limit if you are going to visit a dying relative. That's ridiculous. Think about it. If I was going to visit a dying relative (who you have never met) would you be happy for me to drive at 100mph along the street where you live?
bluesnowmonkey 14y ago
A self-driving car would be handy in situations where you are alone and injured, with the capacity to get to your car but not to drive safely. Severe illness, power tool accident, bear attack on a camping trip. You just get in your car and say, "Take me to the emergency room." It would actually be faster than an ambulance that had to make a round trip. Also, pretty much the last person we (as a society) want speeding is a tired, stressed, freaking-out, distracted, soon-to-be-husband.

latimer 14y ago

If self-driving cars keep their much safer track record when they start being actually used by the public, maybe they can adapt the carpool lane to be a self-driving car lane which has a higher speed limit?

rocky1138 14y ago

This will no longer be a problem if all cars are self-driving. Then, they can just up the limit incrementally. Possibly even to something much faster than a human could do manually.

stewie2 14y ago

I think the first usage of self-driving cars is for public transportation. With this technologies, crowed areas could have more self-driving buses. or use it to replace long distance truck drivers.

asher_ 14y ago

Road speed limits are based on standards that take in to account the environmental circumstances of the road - straightness, visibility, etc - as well as having a huge amount of safety buffer built in to account for human reaction time. If self driving cars become ubiquitous, there is no longer a reason to have this buffer built in. Perhaps the whole idea of posted speed limits will become obsolete if the software determines the maximum speed in the moment for a certain risk tolerance.

pasbesoin 14y ago

Part of the problem is that communities keep lowering the speed limits below recommendations and even the guidelines of law. My father, who has a background in urban planning, is fond of, or frustrated enough to point this out. A street that, per our state's code and regulation, should be 45 mph, gets dropped to 40, then to 35. Nothing significant has changed with its facing development and use. But the community, or of some excess of caution or some orthogonal desire for control, keeps ratcheting it down. In other spots, they start putting up stop signs at every block. They aren't really warranted, but in a variety of "think of the children" attitude, perhaps combined with a twist on NIMBY (Not In My Back-Yard) attitude, the through-street needs to "be somewhere else". Until there no longer is a through-street. So fine, have these cars obey the speed limits. But then set reasonable limits, ones that are evidence-based and not politicized.