Robocars will have a huge effect on the way we live in cities, of that I am confident. Just what that effect will be is much harder to predict. It's not sure if anybody truly understands the city and all its emegent properties well enough to come to firm conclusons.
Nonetheless, I think any examination of the city of the future is diminished if it doesn't account for the many potential changes brought about by robocars. I describe many of these changes in other essays, but felt it might be good to outline them briefly here to solicit comment from planners on how they see the robots changing the city.
Transportation has always played a large role in defining all patterns of habitation, be they farms, suburbs or cities. Many would say the car is directly responsible for the birth of the suburb. The density of cities is also regulated by how well people can get in and out of them and move within them.
If you are coming to this article cold, without having read about what robocars are and their many consequences, some of the claims here will seem somewhat far-fetched. You may want to read the other materials linked to on this web site, or other sources, to understand just how quickly this technology is coming.
This article seeks to outline all the issues. A particular vision of Robocar Oriented Development outlines some predicted results.
It is also worth noting that many of these effects take place only as robocar (and in particular robotaxi) penetration becomes fairly high. Many of them are gradual, though, and start affecting the patterns of travel for the robocar users even if they are few.
The robocar trip will be in a pleasant cocoon which has computerized suspension and slow acceleration. It could feature a desk, display, internet, books, videos, videoconferencing or face-to-face seating when moving as a group. The time in the car should be productive work or leisure time, not time taken out of the day. Trips still take time but I have called this the "poor man's teleporter."
(I've also written about slower, more efficient sleeper cars. These could affect where people put vacation homes, or even some commutes.)
The robocar is not a teleporter, of course, and people will not completely disregard travel time. Robocars may offer reliable and quick travel times over short distances. Today a two mile trip can involve traffic congestion, finding and getting in and out of parking and more. The robocar should create a larger zone of destinations that can be reached in very short times, like 5 minutes. This may confer other advantages on density, allowing a dense 2-3 mile zone with a million people who can all get anywhere in under 10 minutes.
Note that congestion reduction of this short requires "smart streets" (robotic or human driven vehicles) and is still some time away.
Elsewhere I detail how robocars might spell the decline of transit because they could potentially be faster, personal, higher capacity and more energy efficient than existing transit systems. Even if transit remains dominant at rush-hour due to capacity constraints, self-driving taxis are likely to supplant it to a large degree in the off hours, radically changing its economics.
The decline of transit also implies changes to transit oriented development, and urban clusters centered around transit hubs and stations. This may be combined with robocar oriented development.
The decline of mass transit will be fairly slow, both because of the time needed for high robocar penetration and the opposition to it due to conservatism and municipal bureaucracy. (I refer to the incorrect opposition here. There will be both valid and invalid opposition, but both types will play a role.)
In addition, I predict a new style of transit will arise to handle the rush hour peaks. Read about it at the future of transit.
Robocars eventually will deliver people door to door, and small electric ones might potentially enter buildings and go right to elevator lobbies -- or even ride some elevators. While people may enjoy walking, it probably will reduce if there is no strict need for it. This may mean less pass-by traffic other than deliberate strollers or people walking short distances -- not even people moving from parking and transit stations to their destinations. Many urban dynamics depend on these walkers. There is also the potential, as parking lots are repurposed, for a reversal of this.
See below for notes on children (who in the suburbs rarely walk to school any more in the pre-teen age groups.)
Robotaxis offer a novel ability for car-users to take one-way trips. This means that having a car take you one place, walking a mile and having a car take you back home is entirely practical. Other mode shift trips, like car-subway-car, or "train downtown, car-back-home" or "carpool to work, robotaxi back home" become practical.
This is at odds with the current approach, where once you use your private car to begin a trip, you must do all legs of the trip (other than round-trip detours) by car. People often drive a short distance with their car (if parking is easy) just to avoid having to walk back to get their car.
While using a robotaxi for all legs of a trip does remain attractive (particularly for the elderly on in weather,) we may see more use of suitable alternate modes for different legs of a trip.
The "Deliverbot" might deliver just about anything in under 30 minutes, not just a pizza. Quick delivery warehouses could send you almost any product in less time and for less money than it would take you to pop out to a nearby store and get it, as long as you don't need to see it in hand to select it. (Don't like it? Send it back and get something different in a very short time.)
Deliverbots offer the potential to rent many things on demand, and get them in a very short time, then be rid of them just as quickly. This goes beyond carpet cleaning machines to large items like guest bedroom furninshings, party hosting gear, a well-stocked workshop or large exercise equipment. People can save money, and space by keeping an area of the house (the former garage?) which changes purpose every day.
Restaurants are a large part of urban character. But they are a notoriously difficult business to run. Many chefs may seek to maintain just a kitchen, and deliver hot, fresh, quality food to people in a radius of a few miles via deliverbot. Beyond pizza, chefs make work taking orders in advance, getting fresh ingredients just-in-time by deliverbot and wasting nothing, and employing no waiters. Restaurants as social places won't go away, but demand will change.
A "destination" retailer or service, such as a major department store or a big cinema may decide it does not gain much advantage from being in a central downtown. With little walk-in traffic, it may move to the outskirts for cheaper rent while still offering short travel times for customers or people going somewhere else in a CBD. This could result in "downtown sprawl." This is already a feature of many late 20th century towns (often suburbs who developed commercial bases) which have no pedestrian downtowns.
Robocars don't park, they "stand" and can do so not just in parking spaces but in front of fire hydrants and driveways, and even in rows triple-parked on the side of streets. My vision of robocars also means much greater use of single-person cars for urban trips, which store in 1/3 to 1/4 the space of current cars, super-valet style. The enabling of siginficant car sharing also means a huge reduction in the total number of vehicles which are not in motion. This is fully detailed in the article on robocar parking.
This means there is far less need for parking lots, which take up a large amount of our urban and suburban spaces. These lots might get repurposed as green spaces, buildings or additional street capacity. People also will have less need for garages in their homes. This allows an increase in urban density for walkability.
Robocars at high penetration also enable one-way streets and narrow streets. The "street" in a residential cul-du-sac may be a small narrow thing, safely shared with pedestrians and cyclists and children.
Grids of one-way streets improve traffic flow and safety, and are much more acceptable to people in robocars. While getting to a particular point may require a small backtrack, it's all handled by the vehicle and the slight extra time is productive, and more than made up for by other improvements in the trip. Streets may also be reversed at rush hour to increase capacity.
Once penetration becomes high, robocars offer the potential to vastly increase the capacity of our existing road network and new roads. This might mean either a lesser need for roads, or more likely more intense use of them. The maximum density of urban spaces is governed in part by transportation capacity. Roboars may enable much larger and more dense cities if this is where market forces drive things.
Other advanced transporation technologies may allow metering of road use so that most roads rarely exceed their capacity. While this reduces congestion, it also reduces residential build-out that goes beyond transportation capacity limits.
So much of the housing decision is based on parents' wishes for children, and the suburb largely exists for this reason. They seek good schools, safe homes with pleasant and private yards, good neighbourhoods and places to play. They want children to have easy access to all their activites and friends. Robocars could take children to school without burdening the parents, allowing easy attendance of remote schools -- even including play visits to friends from that school who live far away. Similarly robocars could take children to soccer matches and other activities, or take children and parents together to parks, play dates and play spaces.
In theory, a child might live on a farm and still participate in school, play and events like an urban child. Will parents push in this direction, or will they prefer pleasant urban spaces with more walking?
Robocars offer mobility for the disabled and the aged who do not have the ability to drive conventional cars. This population has rarely had mobility that's as good as that of the general population, and superior to today's standards.
Because robocars are equipped with cameras and sensors which record everything around them in 3-D, and they will for many years to come retain these recordings for debugging and accident-evidence purposes, they offer the potential for a high level of surveillance of public and private spaces. These are just some of the robocar privacy implications.
Cars form part of the urban landscape, and they will be changing quite a bit as well. There is a different article on engineering changes in cars to consider.
It's not out of the question that robocars might be able to walk short distances as well as roll. Such a car allows houses to be vehicle accessible when they are not on streets. This can alter urban design.
Robots will do more than drive. They may have a role in policing, putting out fires and bringing us to medical help.
They may also change access to airports (the one type of mass transit that will continue to thrive) both large and small, and speed up the whole process and possibly engender a much simpler and cheaper airport design.
They might also plow the streets and pick up the garbage.
Robocars may expand the sphere of utility for urban attractions such as retail streets, restaurant clusters and parks. Being a short walk from such locations is valued and this shows in real estate values. Robocars may expand the zone considered proximate to these attractions by offering a quick, on-demand trip in 1-2 minutes total time to the walkable zone. They are likely to encourage polycentric urban spaces by offering public (taxi) transportation that is not tied to corridors.
This could create the concept of the Neighbourhood Elevator, a small robocar shuttle that works as the analog of the elevators in the buildings of high density urban areas.