Roads
What will autonomous cars mean for cities?
Google revealed this week that it is working on autonomous cars, and making a lot of progress. While it's what engineers call a nontrivial problem, making a car drive itself is ultimately just a matter of engineering, and will sooner or later become a reality.
Photo by dimic- on Flickr.
What will it mean for our cities? Will cars that drive themselves lead to more driving or less? More sprawl or more compact living?
On the one hand, long commutes will become more tolerable. Instead of suffering behind the wheel for hours, commuters who live far from their jobs will at least be able to get some work done or watch TV. This could make distant exurbs a bit more appealing and boost sprawl.
It will also probably cut down on commuter rail ridership, since some people choose rail over driving because they like not having to actually drive. However, even a small increase in vehicle volume will bring many freeways to a halt, making commuter rail more attractive time-wise, so it's not likely to have a large effect.
But the biggest change will be autonomous buses.
Today, buses have fairly high operating costs because of the labor involved. They're far more space-efficient than cars, but it's expensive to pay a driver. The biggest reason transit costs more to operate than highways is because with transit, you're paying a driver, but if you're driving your own car, you're doing the labor yourself.
That's a structural imbalance that puts transit at a budgetary disadvantage, until your car drives yourself and so can the bus. Suddenly, there's no difference.
Cities with self-driving trains, like Vancouver, can run far greater frequency at low ridership times like nights for a reasonable price. More vehicles makes transit more appealing.
Now, buses are often very infrequent or nonexistent at night, making them an unappealing mode for an evening trip, for example, unless you live right near a high-frequency, late night line. But what if the bus just drove itself every 5 minutes? Basically, it's like everything PRT promises, but without any guideways.
Or, better yet, what if it ran on demand? Then it's like a cheap taxi. And, in fact, buses, taxis, and car sharing will essentially merge into one mode.
Right now, each of those modes has advantages and disadvantages. Buses have the labor cost issue. Taxis have it even more, but are very convenient when available. Car sharing is great for certain types of trips, but you have to return the car to its starting point.
With autonomous vehicles, there will be no need to differentiate between vehicles that carry many people on fixed routes (buses), vehicles that carry few people on demand (taxis), and vehicles you can drive but are only in certain places (car sharing).
Instead, you'll simply be able to call a number or use a mobile app to book a trip. In urban areas, you'd go to a designated bus stop, or maybe pay more to get a custom pickup right where you are. A vehicle will show up at an assigned time, maybe picking up a few other people as well who are going to a similar destination, unless you want to buy a solo trip.
For more on how this could work, see Mark Gorton's Smart Para-Transit articles.
We'll need far fewer parking spaces in dense areas. Commuters from suburbs that take autonomous buses/taxis/paratransit vehicles/car sharing cars into the city won't need to park them. Instead, they can drive themselves around all day serving short-range trips as taxis. Others would live in the city full-time, and those might need overnight parking, but far less than we have today.
It will simply become far easier and cheaper to live in the city without a car. It won't really be like living without a car today. It will simply be like living with a car, without worrying about parking or paying nearly as much. Or, perhaps, it's like using car sharing, but with the guarantee that a car is always available and without having to worry about getting the car back in time.
Finally, assuming Google can perfect the software, streets will become much safer. The cars will be far better at avoiding crashes. Instead of most drivers speeding, turning improperly across bike lanes, and being distracted with texting or phone calls or the radio, the car will be "paying attention" at every moment (as long as its software isn't buggy!)
Governments and manufacturers will have to decide how to handle speed limits. Today, many localities set speed limits knowing most people speed. Will drivers be able to choose their speed, or will cars be required to travel the actual speed limit? If so, maybe we can finally rationalize all these limits and set them appropriately.
If governments set up autonomous car-only lanes on freeways or ban human-driven cars altogether once most cars drive themselves, traffic can move more efficiently. Right now, if a bunch of cars are stopped in traffic or at a light, each driver has to wait a few seconds after the car in front starts moving. With computers, the entire line of cars could simply start moving all at once.
The greater efficiency will allow existing freeways to carry more people than they do now, and since it'll be a lot easier to create carpools with Smart Para-Transit dispatching, even more if jurisdictions are willing to convert lanes to HOV. That could also accelerate sprawl, but the greater ease of urban living and lower need for parking will also facilitate infill development as well.
How else will cities change if cars can drive themselves?
 | David Alpert is the Founder and Editor-in-Chief of Greater Greater Washington and Greater Greater Education. He worked as a Product Manager for Google for six years and has lived in the Boston, San Francisco, and New York metro areas in addition to Washington, DC. He loves the area which is, in many ways, greater than those others, and wants to see it become even greater.   |
Comments
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by Paul C on Oct 15, 2010 10:35 am • link • report
by EJ on Oct 15, 2010 10:47 am • link • report
by Steve on Oct 15, 2010 11:05 am • link • report
by Nathan on Oct 15, 2010 11:09 am • link • report
And yes, litigation+unions+customer resistance will demand operators on buses for a long time. And which robot is going to stop fare jumpers?
by charlie on Oct 15, 2010 11:11 am • link • report
by Rob on Oct 15, 2010 11:25 am • link • report
by Redline SOS on Oct 15, 2010 11:33 am • link • report
people will have to buy single ride tickets from the parking meters before boarding, or have a pass or electronic farecard.
by Michael Perkins on Oct 15, 2010 11:39 am • link • report
I'm not sure that would be true. The required stopping distance increases with speed, and that is constant whether there is a human driver or not. I don't think it would be possible (or desireable) to have a line of cars going 40 MPH only separated by 2 feet.
by engrish_major on Oct 15, 2010 11:39 am • link • report
by dan on Oct 15, 2010 11:41 am • link • report
by Bossi on Oct 15, 2010 11:44 am • link • report
Insurance could play a constructuve role. ALl this creates good data on a driver's true risk. Possibly also lower rates for those who do not make mistakes. Failure to yield to a pedestrian could ring a bell and add a calculated risk factor, so that at least some people would stay engaged in their driving even while it became safer. Companies might also provide lower rates for giving up some autonomy to violate traffic rules (albeit with manual over-ride to do so always there), but regardless the data would encourage it in a way that only one's conscious or a speed-cam do today.
by Jim Titus on Oct 15, 2010 11:47 am • link • report
by Michael Perkins on Oct 15, 2010 11:48 am • link • report
by Simon on Oct 15, 2010 11:49 am • link • report
by dand on Oct 15, 2010 11:50 am • link • report
by engrish_major on Oct 15, 2010 11:56 am • link • report
by Michael Perkins on Oct 15, 2010 12:01 pm • link • report
Think of it this way. A semi pulling a trailer has 2 independent pieces, connected with a bar. (Some have more.) When it's at rest, the trailer is a certain distance from the cab. When it speeds up, they're still the same distance. The trailer doesn't need to back up 20 feet to maintain a stopping distance. Thet's because as soon as the cab hits the brakes, the trailer will start to slow down immediately.
In longer combo trucks, I think there are rear brakes that are separate, but connected by wire to the cab. As soon as the driver hits the brakes, the extra rear brakes kick in too. Again, this allows the whole unit to stop at once without needing stopping distance in between.
For the autonomous vehicles, think of them as a big long single vehicle. They start as one and stop as one. They can be any tiny distance apart, as long as they act as one. Maybe there will be a small delay based on the communications protocol, but that's miniscule.
Of course, this assumes that the communication is pretty darn reliable. You'd need to make sure there were backups. Maybe they communicate by Wi-Fi, and also each car talks to the next via infrared, giving two ways to keep in touch.
by David Alpert on Oct 15, 2010 12:04 pm • link • report
You write that "even a small increase in vehicle volume will bring many freeways to a halt, making commuter rail more attractive time-wise, so it's not likely to have a large effect." I disagree. Traffic is caused primarily by human error, not by volume. Autonomous cars could drive with virtually no space between them because there would be no sudden stopping. Imagine a line of cars with only inches between them moving at speeds unimaginable by today's standards. These cars would also be extremely energy efficient because of gains made from drafting and the ability to eliminate safety measures from cars and use light weight materials.
You also write that "right now, if a bunch of cars are stopped in traffic or at a light, each driver has to wait a few seconds after the car in front starts moving. With computers, the entire line of cars could simply start moving all at once." Here too, I think you are not seeing the full potential. There would be no need for lights at all. Fully automated cars could coordinate with cars coming on cross streets and adjust speeds so as to avoid a collision. There is no need to come to a full stop.
by David G. on Oct 15, 2010 12:05 pm • link • report
What about pedestrians?
@David Alpert: That is a good point. I had not thought of the cars communicating with each other.
by engrish_major on Oct 15, 2010 12:12 pm • link • report
I see limited utility in driverless vehicles. Say industrial areas, or in airport. Highways-- maybe But really, once you introduce other drivers to the mix it will be very hard to control any computer.
I forget the number, but I think the average american driver an accident every 1 million miles -- given that may people go years or lifetime without an accident. 140K miles driven isn't very impressive.
by charlie on Oct 15, 2010 12:18 pm • link • report
For dense urban centers, there would still need to be lights for this reason. In less densely populated areas with larger arteries, I think that lights could largely be eliminated. If a pedestrian were to cross one of these roads, autonomous cars would react accordingly.
by David G. on Oct 15, 2010 12:21 pm • link • report
by imperator3733 on Oct 15, 2010 12:22 pm • link • report
I think before we even think about using computers to drive our cars in congested urban areas, we have to figure out how to more intelligently provide facilities for all users.
We complain today about liability not being assigned to drivers for hitting peds and bikes, but how do you assign liability to a computer?
by neb on Oct 15, 2010 12:23 pm • link • report
by imperator3733 on Oct 15, 2010 12:25 pm • link • report
In theory no need for a formal bus network and you route home from work could change every day depending on demand and the number of buses on the road. In practice buses would radiate out from heavy traffic generators along main roads, with neighbourhood circulators doing the final leg.
Unlikely in the near future, but it is more likely if there is no affordable alternative to gas powered private vehicles and electric ones remain expensive. It would allow people to still live in suburban cities, which with little traffic would be a breeze to commute from.
Sure changing vehicles 3 or times is nightmare now, but if it took less than a minute each time and you had no anxiety about missed connections probably not a problem. If it replace most peoples journeys then it would be fairly fast if there were also express options for longer distance routes.
by Rational Plan on Oct 15, 2010 12:27 pm • link • report
by Fritz on Oct 15, 2010 12:46 pm • link • report
What happens to people who do not have phones or other capable device ?
by kk on Oct 15, 2010 12:54 pm • link • report
Currently we charge about $1.00 on average for trips that cost $4. If we can drop the cost with lower operating cost, and at the same time get higher ridership by running more frequent vehicles, we might be able to get effective fares down to $0.25, and that's when it gets interesting, because you start getting to the point where it no longer makes sense to attempt to collect a quarter.
by Michael Perkins on Oct 15, 2010 12:55 pm • link • report
I predict most American cities will choose the latter, and European cities will pick the former. In those cities, there will be four rush hour periods a day, as the cars that drive their owners to work then drive home for parking, and drive back to work in the afternoon to pick up their owners.
This assumes we aren't doing a lot more telecommuting, of course.
by Michael Perkins on Oct 15, 2010 1:13 pm • link • report
It will probably be decided similar to other cases involving defective products. The plaintiffs lawyer would have to prove that the product was defective in some way. Sort of like if the brakes malfunction on a car and it strikes a pedestrian.
I would expect the plaintiff to try to prove that the design or maintenance was faulty. Before such a car was offered for public sale, I would expect there to be NHTSA regulations regarding testing. There might even be a congressman working on a bill right now based on the Google story.
by Michael Perkins on Oct 15, 2010 1:25 pm • link • report
by Thayer-D on Oct 15, 2010 1:44 pm • link • report
The only automated function that cars operated in DC will have in the next 5-10 years will be speed-limiters.
by oboe on Oct 15, 2010 2:01 pm • link • report
by Rational Plan on Oct 15, 2010 2:02 pm • link • report
There are lots of people without electronic devices around the global. I know many people who choose to not have cell phones or mp3 players because they are of no use to them and can do all there business without them or in the case of the cell phone without paying a monthly fee.
So what about people from foreign countries or people who choose to not have them; what if someone normally doesn't take the transit and has to due to emergency.
by kk on Oct 15, 2010 7:35 pm • link • report
- Automated freeways become the dominant method of transportation due to vastly improved safety, improved capacity due to vehicles travelling closer together, higher maximum speeds of up to 200km/h (when there is no traffic congestion), and high redundancy.
- Suburban sprawl continues its march unabated. Automated cars and buses will make long commutes more tolerable, but of course the trend of jobs moving to the suburbs will continue.
- Traditional non-car oriented walkable cities will decline but remain popular with a small minority of the population. On the other hand, many newer suburbs will begin to resemble traditional walkable cities in some ways, while remaining highly accessible by car as well.
- There is a proliferation of cheap robotic taxis which reduce the need to own a car and the need for parking. Personally owned cars remain popular largely as a status symbol, despite the high cost of owning a car and parking, but fewer people feel the need to own one.
- Public transit in big cities mostly takes the form of large numbers of robotic buses, which are able to run at much lower cost thanks to elimination of the human driver. Rail disappears except perhaps in the very largest, high density cities because a lane of robotic buses can carry more passengers than a bus lane, because buses have better redundancy (a closure of a freeway causes less disruption than a closure of a subway line), and because there is less need for transfers. High speed/intercity rail disappears completely being inefficient and costly compared to robotic buses and cars. Taxis act as feeders to buses, with commuters often transferring to and from taxis at the end of their trips to access areas not accessible by bus.
- Public transit in small cities and rural areas declines (operates only on congested routes at rush hour) or disappears completely. Public transit at low-demand times of day (e.g. late at night in low density suburbs where there is little car traffic) disappears and is replaced by taxis.
- Automated trucks proliferate and displace freight rail. The cost of delivery services decline, so online shopping becomes much more popular and much faster (e.g. order groceries online, have them appear within 1 hour), and retail mostly disappears.
by Andrew on Oct 16, 2010 12:10 am • link • report
The same problem appears in commercial aviation. Aircraft have become so heavily automated that pilots have little to do. Unless they are given something to do to keep them alert and aware of their surroundings, the result is crashes and separation violations resulting from inattention.
The moral of the story is that all automated forms of transport have to have dedicated rights of way and centralized human monitoring for safety.
by Chuck Coleman on Oct 16, 2010 9:43 am • link • report
What we might see is more automation that helps drivers (who won't go away) avoid many kinds of accidents. That might be an interesting topic to discuss. But the idea of doing away with drivers and cutting costs is pure fantasy.
by David desJardins on Oct 16, 2010 3:27 pm • link • report
But I can imagine that in one of these taxi-like vehicles on private roadways(all streets and roads can be privatized down to inch if its possible to track and charge the users of them), you have no intrinsic rights, to be anywhere or do anything or say anything, whatsoever without consent of the property owner(vehicle, road, or all-in-one corporate
"city").
This will be an interesting thing on the magnitude of when the Supreme Court had to address the issue of interstate commerce back in the 19th century,
by TXSteveW on Oct 16, 2010 4:28 pm • link • report
by Amanda on Oct 16, 2010 9:46 pm • link • report
This seems to me still a bit beyond the bounds of feasibility in any foreseeable future, if you are talking about a system that will run cars at a much higher speed than would be safe with human drivers. What happens when debris is in the road? Or when a car in a neighboring lane drifts into the lane? Or the car in front of you blows a tire? I don't think the potential density gains are as large as you imagine---cars still need a buffer for stopping even if automated---and the potential for relatively rare but high profile accidents seems high.
by David desJardins on Oct 16, 2010 9:52 pm • link • report
Maybe some cities where people are forced to live in a uncomfortably dense, overpriced area they don't really have any attachment or pride in only because of transportation to where they work, that will happen.
But I think actually, depending on the formula in which these cars work, the most optimal places will be moderately dense and diverse, decentralized but also mixed-use.
Remember the issues with bike sharing and how bikes end up scattered around outer neighborhoods? Robotaxis may drive themselves back but that is not as efficient, or profitable for the operating companies, as if those cars could be moving people in both directions.
People will want to live in places and be subscribers of the robotaxi companies which can provide the fastest trips and least wait times and are also the cheapest. These will be the places where movement is the most efficient(riders on both ends, short trips due to density), and the cheapest will be places where you can have the lowest ratio of shared vehicles to users thanks to the first two factors.
Using a robocar in suburban Atlanta may cost more and take longer than in Portland. Of course, it may cost more in New York too.
Another idea is that with tons of data from knowing all the customer data is that new communities can be planned optimally with little guess work.
by TXSteveW on Oct 17, 2010 1:06 pm • link • report
If that goes away, and people essentially become passive passengers in a small bus, will cars be as popular? Just asking.
by John Schneider on Nov 1, 2010 10:00 am • link • report
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