It's one of the better videos I've done, and if you have heard my talks in the past, you'll find this one pretty new.
It's one of the better videos I've done, and if you have heard my talks in the past, you'll find this one pretty new.
By Evan Landman.
Last summer, we covered an exciting new transit planning tool called Transitmix. Transitmix grew out of a Code for America project that sought to create a web-based tool to automate much of the complex yet mundane work that goes on in the background during transit planning. Cost estimation, line measurement, population and employment coverage analysis, are all examples of tasks that require time and effort such that they cannot all be carried out in real time during a planning meeting or workshop.
The team at Transitmix reached out to transit planners all over the county (including our firm), learning what did and didn't work about current practices and workflows. They created a beta version of a simple online tool that hinted at what might be possible. Finally, last week, Transitmix released a new video announcing the impending release of the professional version of the application, with critical features that offer the promise of a dramatically simpler, more open, and more easily understood transit planning tool.
Dynamic demographic and employment mapping and analysis, and side-by-side network and route comparisons are the main new features implemented here, to go along with the live updated costing, and deeply configurable frequency, span, and cost parameters the older version already includes. Transitmix continues to impress, creating a tool that simplifies and demystifies procedures that are too often known only to practitioners. We look forward to getting our hands on the full-featured product.
I talk a lot about altitude in planning and network design. But sometimes my airplane metaphor gets mangled a bit in translation, as in this otherwise fine article about our work in the Raleigh, NC area.
So wherever you encounter it, here is what I mean:
If you are higher up from the surface of the earth, you can see a larger area, but in less detail. At lower altitude, you see a smaller area, but in greater detail.
Likewise, there are high-altitude planning projects, which look at a large area (a city, a county, an urban region) and identify appropriate solutions to problems that exist at that scale. There are also lower altitude projects, all the way down to parcel-level development approval, or, in my business, detailed designs of a transit station or a bus schedule.
One of the basic skills you should expect from a planning professional is the ability to control altitude. As in a plane, you need to get up high to see the big picture. If you don't, you'll make decisions that produce bad consequences outside the small frame of the low-altitude problem you were focused on. For example, if land use planning is nothing but development approval, then stuff will get built, project by project, without any attention to the aggregate consequences of that development -- on traffic, on livability, on natural resources, etc.
On the other hand, plans that remain at high altitude -- regional structure plans, vision plans, "strategic" plans, etc -- don't have any effect on reality unless they're implemented by actions at lower altitudes.
So the airplane metaphor works like this: To see clearly, we need to get our plane to a high altitude. But to implement anything, we then need to land the plane.
The key is to lose altitude in a controlled and intentional way. You look at the problem at high altitude and see the solutions that make sense at that level. Maybe, for example, you identify a corridor that should have some kind of rapid transit but you don't specify what the technology should be, or even an exact alignment. Then, later, a study focuses just on that corridor and explores all the options for it. All the remaining steps from there to implementation are part of a controlled loss of altitude until finally, on opening day, you're on the ground: The thing you planned is actually happening.
However, there is always the danger of uncontrolled loss of altitude, i.e. crashing the plane. This happens when a conversation at a certain altitude is interrupted or shut down by a low-altitude issue. For example, when we're exploring the possible structure of a citywide network in a city, an operations manager may interject that a particular turn isn't possible, or that this business would never let us put a bus stop there. Those comments are plane-crashers. If we succeed, at high altitude, in developing a network vision that excites people so that they want it to succeed, all those problems will be easy to solve. But if we let those little concerns veto the high-level thinking, we'll never be able to talk about the big picture.
This comes up often among people who have strong emotions about particular transit technologies. They fervently support or oppose some technology option, so want to know the answer to the technology question before we have properly thought through higher altitude questions: What are our goals for transit? How do we balance predictably competing goals? What kind of citywide network do we want? What kind of mobility and access do we want to provide?
If those sound like hopelessly abstract questions, read the introduction to my book. There, I explain how we can approach these questions so that citizens can answer them with an awareness of the consequences. That, in turn, means that the decisions they make can be implemented. The plane can descend, and finally land. The key, as I explain there, is to listen to your plumber!
Photo: Airplane Contrails- Creative Commons: Ian Renton, 2011
Last summer, we tested driverless minibuses along a route of 1.3 km on a pedestrianized boulevard in Oristano, a small town in Italy. The idea was to test driverless vehicles mixed with traffic.
Why minibuses and not taxis? Firstly, because it is much simpler to teach a robot to follow a fixed route, rather than teach it to go anywhere the passengers want to go. Such a system is already operational in Rotterdam (2getthere.eu/projects/rivium/) and it works well, but it has one drawback: the tracks are segregated and they represent an ugly severance in the urban tissue.
But if the vehicles are allowed to run with cars cyclists and pedestrians, a public transport route can be “adapted” with unobtrusive measures to accept driverless vehicles, and the people sharing the road will quickly learn to live with them. The main problem here was not technical, as legal.
Hence the idea of testing similar vehicles in an open field mixed with pedestrians. The first test we did had mixed results, the second test that will be done in La Rochelle, France this winter will take advantage of all that we learned in Oristano.
So what did I learn from all of this? That driverless cars very likely have a bright future, but cars they will always be. They may be able to go and park themselves out of harm’s way, they may be able to do more trips per day, but they will still need a 10 ft wide lane to move a flow of 3600 persons per hour. In fact, the advantage of robotic drivers in an extra-urban setting may be very interesting, but their advantages completely fade away in an urban street, where the frequent obstacles and interruptions will make robots provide a performance that will be equal, or worse than, that of a human driver, at least in terms of capacity and density.
True, they will be safer (especially because the liability for accidents will be borne upon the builder) and a robotic traffic will be less prone to congestion (I envision robotic cars marching orderly like robots, packed at 1.5 second intervals, while their occupants fume wishing they could take the wheel perfectly aware, but not at all convinced that their robocars are more efficient drivers than they are – or worse, they DO take the wheel overriding the ... robots!), but I do not expect driverless cars to dramatically increase the capacity of a lane to transport persons.
Driverless buses, on the other hand offer an interesting feature: the human driver is no longer needed, removing an important cost and several constraints. This allows them to serve efficiently and economically low-demand routes and time bands, while allowing [agencies] to concentrate the number of manned buses on high demand routes at little added cost.
I take all this automation talk with a grain of salt still, as I don't think we've begun to explore the human response to it. But Luca is right about the key point: driverless buses are a much easier problem than driverless cars, and their space-efficiency will continue to be crucial in busy corridors where even driverless cars will add up to gridlock.
Luca's last paragraph suggests that driverless buses will start with smaller vehicles in simpler situations, which is a possibility. But of course, once the concept is proven, the economics of driverlessness will create pressure to bring the technology to big buses. The same logic is also driving the movement to run fully-grade-separated without drivers, on the model of Vancouver, Dubai, and Paris. The logic of driverless trains is easy: with automated train controls systems there is really not much for a driver to do in non-emergency situations, and these cities have found that those tasks are easily automated. We are all used to small systems of this type, because we encounter them in large airports. The driverless bus in traffic is a harder problem, but we will have solved all of those problems if we ever develop driverless cars. In fact, the problem of the driverless bus, which never goes into alleys or minor streets, should be considerably easier, since navigation turns out to be one of the biggest challenges for the driverless car.
Note also that the challenge of planning for driverless cars is not in envisioning a utopia where they have complete dominion over the street. The future must be evolved, which means that we must plan for the interim state in which some cares are driverless and most aren't. That is a situation where driverless buses could thrive, because they will be competing with something that -- in terms of poor capacity utilization -- resembles today's traffic on major streets, not a world optimized for the driverless car.
As Luca indicates, we know what the problem with driverless transit will be: long fights with labor unions who feel entitled to cradle-to-grave security in a single job. It will be one more kind of automation that requires people to retrain and to participate in a more complex and competitive economy. In an ideal system, many drivers would be replaced by support jobs such as fare inspectors and roving problem-solvers; as on Vancouver's SkyTrain. This seems to be what Luca is envisioning when he speaks of the continued need for "manned" services.
But the real result of massively abundant transit -- which is the real point of the large driverless bus -- will be massively more opportunity for all kinds of innovation and commerce to happen in a city, unconstrained by the limits of car-based congestion. That's a wrenching change, and I am as adamant as anyone about the need to protect workers from exploitation. But in the long run, over a generation or two, the outcome will more interesting jobs for everyone. Bus drivers shouldn't encourage their children to go into the same profession with the same expectations, but that's true of many jobs -- perhaps even most jobs -- in this rapidly changing world.
Is transit headed for a collision with self-driving cars? David Z. Morris in Fortune writes about how anti-transit Republicans are using the prospect of self-driving cars to argue against transit investments.
Alarmingly, he quotes nobody who can actually refute this argument, except in the fuzziest of terms.
Here is the recommended response:
We are currently in that phase of any new techno-thrill where promoters make grandiose claims about the obsolescence of everything that preceded them. Remember how the internet was going to abolish the workplace?
In any case, technology never changes facts of geometry. However successful driverless cars become, transit will remain crucial for dense cities because cities are defined by a shortage of space per person. Mass transit, where densities are high enough to support it, is an immensely efficient use of space.
(Remember, a great deal of bus transit is in places where densites are not high enough to allow it to succeed; this is evidence of anti-ridership "equity" or "coverage" policies, not of transit's failure. Driverless taxis could certainly replace transit in those areas, assuming the pricing were gotten right, thus allowing transit agencies to focus on their core business.)
In many cases, conservatives talking about driverless cars are talking exclusively about the interests of their own outer-suburban constituents, who tend to live in low-density, car-dependent places that are unsuited to high-ridership transit.
But all over the world, people are moving into dense cities, where even autonomous cars can't replace a bus full of 60 people or a train full of hundreds. There simply isn't enough space to put walls between every pair of travellers, as the car model of transportation requires. Nor will driverless taxis ever be there whenever you need them as great transit lines will. Like bikeshare systems, they will experience surges where many of the vehicles are in the wrong place.
A place the size of Tampa - St Petersburg can of course choose to sprawl and avoid density to the point that driverless cars could dominate. But in so doing it will fail to create a place that the 21st century economy will reward. Real estate prices are already telling us that the market has chosen dense cities as the highest value form of development. There is no dense city in the world that does not rely heavily on transit, for reasons of space-efficiency that none of the new technologies can change. (Yes, autonomous vehicles will use space more efficiently than private cars do, but this is saying very little compared to what a great rapid transit network is achieving.)
Again, technology never changes geometric facts. And the problem of cars in dense cities, and transit's superiority there, is a geometric fact, a fact about space and its scarcity.
Trains would be just one layer of a comprehensive, multi-modal network that greatly enhances both neighborhood and regional accessibility for people all across the [Los Angeles] region. ...
A singular focus on rail would divide the region into two: neighborhoods with rail and neighborhoods without. Such a future would perpetuate income inequality as housing costs rise near stations and station areas would be choked with traffic congestion. ...
Getting our existing buses out of traffic is the quickest, most cost-effective means to bring high-quality transit to the greatest number of Angelenos.
This is from a collection of commentary about the the role of rail in the larger context of transit investment strategies. Read the whole thing!
Our friends at the Transit Center are supporting a new ioby project to crowd-source ideas about how to improve the experience of commuting. If you aren't familiar with ioby, they are basically a crowd-funding platform focused on small-scale neighborhood improvement projects. Have a look at the promo video for the project:
Similar to better-known sites like Kickstarter and Indiegogo, ioby users are able to upload a project and create a funding goal which people who visit the page can contribute to. Examples of projects funded in this manner include community gardens, playgrounds, and environmental education programs, but now, ioby is offering a funding match up to $4000 for ideas related to transit. Have a look at the page for yourself here.
The guidelines for a project seem pretty open-ended:
1. Your project must do one of the following:a. Be a non-digital tool that improves the public transportation experience, orb. Focus on a single node within a transit system, but can be of any mode, i.e., a train station, a bus station, a bus shelter, subway or metro stop, bike share docking station, or parking lot, orc. Encourage the use of clean transportation, in other words, have less environmental and social negative impacts than a single occupancy private car. Some examples include transit, bicycling, bike share, rideshare, carpool, car share, or vanpool. We will consider modes and shared systems that aren’t identified here as long as they are less environmentally and socially harmful than a single-occupancy vehicle, ord. Be something else in this spirit of the shared public transportation experiences! Talk to us! We don’t know all the great ideas out there! (email@example.com)
On this blog, we focus to a great degree on what transit agencies can do to improve transportation outcomes in terms of network design and other aspects of the planning and operations of transit systems. But ioby's new project asks an interesting question: what small-scale, locally sourced ideas can people put into practice to make the transit experience more useful?
Share your thoughts in the comments below, or better yet, head over to ioby and get your idea funded!
I don't have time to respond to everything that gets published on transit, but Robert Steuteville's must-read piece today on the Congress for the New Urbanism blog, which explains why we should invest in transit that's slower than walking*, certainly deserves a response.
Fortunately, sometimes an email does it for me. From Marc Szarkowski:
Perhaps you've already noticed this piece and are already penning a response (even though several already exist on your blog!). It seems to be another example of the "urban designers are from Mars, transportation planners are from Venus" phenomenon you described some time ago.
I admire and respect Robert, and I think his "place mobility" concept is quite sensible. Indeed, one can argue that the first and most powerful rung on the transportation "efficiency" ladder is to ensure that destinations are within walking/bicycling distance wherever possible, obviating the need for cars and transit in the first place, in turn freeing up the latter two for long-distance travel. But after the "place mobility" concept, I think the article begins to fall apart.
It seems to me that it's easy to romanticize slow transit if you don't have to rely on it all the time. With all due respect, I get the impression that many "streetcar tourists" use transit only occasionally when visiting a new city, or perhaps to go to a ball game, but for little else. And I get it: if much of your day-to-day travel is characterized by routinized, featureless car trips between work, shopping, meetings, and whatnot, I can see the allure in taking a break to relax and 'go slow,' as it were.
But the romantic impulse towards slow transit wears away quickly if you have no choice but to rely on it all the time! I don't have a car, so I rely on buses that travelexcruciatingly slowly, wasting much of my time. (I have, for example, learned to pad an hour between meetings and appointments in different parts of town, simply because the mixed-traffic transit takes so long to get from A to B to C.) So, rather than viewing slow transit as an opportunity to unwind and watch the street life pass by, I see it as a precious-free-time-gobbler.
I love to be immersed in street life when I'm walking, but when I inevitably need to travel beyond walking distance, I want to get there quickly. Does this make me a so-called "speed freak?" If so, wouldn't all the urban designers out there praising slow transit for others - while they hurriedly shuttle from charrette to public input meeting to office to daycare in their cars - be "speed freaks" too? The reality is that most of us - walkers, bicyclists, drivers, and transit riders alike - are "speed freaks" most of the time, simply because we prefer minimizing travel time and dedicating our precious free time to friends and family.
And this gets back to "place mobility:" it is great when many daily necessities - the grocery store, the bank, the library, the elementary school - are within walking distance. But - and this perhaps reveals a conceptual flaw in New Urbanism - not every place can or should be a self-contained "village." As Jane Jacobs argued, the whole point of cities is to offer rich opportunity - opportunity that requires travel beyond whatever a "village" can offer: "Planning theory is committed to the ideal of supposedly cozy, inwardly-turned city neighborhoods. [But] city people aren't stuck with the provincialism of a neighborhood, and why should they be – isn't wide choice and rich opportunity the point of cities? (Death and Life, 115-116)."
For example, I may be fortunate enough to have a daycare center on my block, but perhaps I want to send my kids to a magnet or private school across town - a school better than my neighborhood school? So would my kids rather wake up at 5am to take a streetcar sitting in traffic to get to school, or wake up at 7am to take a faster subway or a bus on a bus lane? I may be fortunate enough to have a pharmacy on my block too, but what if the doctor I trust is across town? Would I rather take the whole day off from work to take a streetcar sitting in traffic and delayed by a poorly-parked car to get there, or could I take a half-day by taking the subway or the crosstown express bus? For better or worse, there will always be long-distance destinations, and I suspect transit riders will continue to prioritize speed for these trips.
As for the short, local trips made possible by "place mobility," I still wonder whether mixed-traffic streetcars are the best bang for the buck. Yes, they are a placemaking tool, but they're not the only (or the cheapest) one. If, as admitted in the article, mixed-traffic streetcars don't particularly offer useful transit, nor are they necessarily the only/best/cheapest placemaking tool, then I have to wonder if 30 years from now we'll look back on them as yet another expensive urban renewal fad. (American cities are still littered with half-dead "game changing" fads from the 50s, 60s, 70s, and 80s.) We ultimately need rapid transit and "place mobility," but mixed-traffic streetcars are hardly a prerequisite for creating the latter.
So far I've hesitated voicing these opinions to fellow urbanists because I don't want to alienate any friends, but I'm increasingly skeptical of the streetcar fervor. Given that (A) mixed-traffic streetcars are simply slower and less-flexible than mixed-traffic buses, and (B) that the benefits that are packaged with properly-prioritized streetcars (dedicated lanes, signal priority, durable shelters, etc.) could just as easily be packaged with buses, I wonder if the streetcar fervor is an example of simple "technograndiosity." At the end of the day, I'd rather have ten bus lines reaching twenty useful places than one streetcar line reaching two useful places.
(Marc Szarkowski creates plans, models, diagrams, and illustrations of urban design, streetscape design, and planning proposals, and is a regular rider of Boston's, Philadelphia's, and Baltimore's transit systems.)
*Most new streetcars in the US have average scheduled speeds of 6-10 mph, a jogging or running speed for able-bodied adults. However, actual travel time (compared to a private vehicle alternative) includes the average wait time. Most US streetcars are not very frequent (usually in the 15-20 minute range) given the short trips that they serve, so it is the high wait time, combined with the very slow ride, that makes them slower than walking. Again, this calculation describes the experience of an ordinary working person who needs to get places on time, not the tourist or flaneur for whom delay is another form of delight.
Transportation planning is full of projections -- a euphemism meaning predictions. Generally, when we need a euphemism, it means we may be accommodating a bit of denial about something.
Predicting the future, at a time when so many things seem to be changing in nonlinear ways, is a pretty audacious thing to do. There are professions whose job it is to do this, and we pay them a lot to give us predictions that sound like facts. I have the highest respect for them (all the more because what they do is nearly impossible) but only when they speak in ways that honor the limitations of their tools.
Good transportation planning does this. at the very least, it talks about future scenarios rather than predictions, often carrying multiple scenarios of how the future could vary. Scenarios are still predictions, though; they're just hedged predictions, where we place several bets in hope that one will be right.
I will never forget the first time that I presented a proposed transit plan and was told: "that's an interesting idea; we'll have to see how it performs." The speaker didn't mean "let's implement it and see what happens." He meant, "let's see what our predictive model says." You know you're inside a silo when people talk about prediction algorithms as though they are the outcome, not just a prediction of the outcome that is only as good as the assumptions on which it's built.
What's more, we seem to be really bad at predicting curves, or even acknowledging them as they happen.
Something really important happened in the US around 2004, which experts call the "VMT Inflection." Vehicle Miles Traveled in the US -- the total volume of driving -- departed from a linear growth path that it had followed for decades, and went flat. Here's the same curve looking further back. Around 2003, you could be forgiven for thinking that this steady slope was something we could count on.
(At this point an ecologist or economist will point out that the VMT inflection shouldn't have been a surprise at all. This graph looks like what a lot of systems do when their growth runs into a capacity or resource limit. The VMT inflection is a crowdsourced signal that the single-occupant car is hitting a limit of that kind.)
So reality changed, but the Federal projections didn't. Even as late as 2008, when the new horizontal path had been going for four years, Federal projections claimed that the growth in driving would immediately return to the previous fast-rising slope. Again:
This isn't prediction or projection. This is denial.
All predictions rest on the assumption that the future is like the past. Professional modelers assume their predictive algorithms are accurate if they accurately predict past or current events -- a process called calibration. This means that all such prediction rests on a bedrock idea that human behavior in the future, and the background conditions against which decisions are made, will all be pretty much unchanged, except for the variables that are under study.
In other words, as I like to say to Millennials: the foundation of orthodox transportation planning is our certainty that when you're the same age as your parents are now, you'll behave exactly the way they do.
We describe historical periods as "dark" or "static" when that assumption is true. Over the centuries of the European Middle Ages or Ancient Egypt, everyone acted like their parents did, so nothing ever seemed to change except accidents of war and the name of the king or pharaoh. Our transportation modeling assumes that ours is such an age.
Historical progress arises from people making different choices than their parents did, and there seems to be a lot of this happening now.
What we urgently need, in this business, are predictions that try to quantify how the future is not like the past; for example, by studying Millennial behavior and preferences and exploring what can reasonably be asserted about a world in which Millennials are in their 50s and are in the position to define what is normal, just as their parents and grandparents do today.
We already know that the future is curved. (With rare exceptions like the growth of VMT from 1970 to 2004, the past has been curvy as well). Millennials are not like their parents were at the same age. There will be major unpredictable shocks. There are many possible valid predictions for such a future. The one that we can be sure is wrong is the straight line.
My work on Abundant Access -- part of the emerging world of accessibility studies -- is precisely about providing a different way to talk about transportation outcomes that people can believe in and care about. It means carefully distinguishing facts from predictions, and valuing things that people have always cared about -- like getting places on time and having the freedom to go many places -- from human tastes that change more rapidly -- such as preferences and attitudes about transit technologies. It's a Socratic process of gently challenging assumptions. Ultimately, it's part of the emerging science of resilience thinking, extending that ecological metaphor to human societies. It posits that while the future can't be predicted there are still ways of acting rightly in the face of the range of likely possibilities.
Imagine planning without projections. What would that look like? How would we begin?
Transitmix is a sketching tool for transit planners (both professional and armchair) to quickly design routes and share with the public.
Transitmix is simple way to think about transit in terms of bus requirements and real costs. Basically, the user draws a route on a map and plugs in span and frequency. The app then calculates a vehicle requirement and cost in both hours and dollars, factoring in an adjustable layover ratio, average speed and dollar cost per service hour.
Transitmix is very similar to (though much simpler and prettier) the sort of cost estimation methods used in transit design processes , and as it stands is a fun sandbox to think about transit in your city. It's still very much a beta, but the prospects are intriguing.
Its clear that the developers of Transitmix see it as much more than a curiosity. They've actively sought feedback from people in the industry, and are working hard to build an app that could one day replace some of the tedious documentation work of network design with an interactive, visually attractive interface. Apparently functions like summary tables, GIS file exports, and the ability to save multiple iterations of one design are all in the works.
I can imagine all sorts of possibilities for a tool like this, particularly if secondary data sources were incorporated. How about a public or stakeholder involvement process that would actually give people a way to view demographic and ridership data and make real, financially constrained transit choices with a familiar, modern toolset? Or an update to our transit network design courses, where participants are given the same information for a fictional city and asked to design a transit network from the ground up? It's great to see transit concepts picked up by a talented group from an organization as reputable as Code for America. A project worth keeping an eye on!
From Henry Mulvey, of Massachusetts:
Hello, my name is Henry Mulvey, I am a tenth grader. I am a huge streetcar fan and I love the old Boston Elevated Railway. I hope to attend M.I.T. for urban planning then work the M.B.T.A. or the state on a big replica streetcar plan for the city of Boston. I just read your article saying streetcar aren't what they seem and I have some rebuttal points. I'm going try my hardest to be civil because I am a die-hard streetcar fan. The two things I see that you either underestimate or don't mention are the aesthetic appeal of streetcars and the environmental costs of buses. Streetcars look very different than buses and people like that. In the case of replica streetcars, they might not carry as many passengers as modern types but they make people think "ooh, that's cool! I want to ride!". Streetcars are more attractive than standard old buses, even an updated bus! Streetcars are also more environmental friendly than buses. Ideally streetcars do not omit any pollutants and are much more efficient than buses. I also think the connection between streetcars and economic development is well documented and you don't provide any evidence to the contrary, can you give me evidence? It's my belief that a streetcar line that uses replica streetcars does both provide great transit and showcases history. Boston is a city that loves history and has a need for streetcars so I think a streetcar would work incredibly there. Thank you for listening to me, Henry Mulvey
Vehicle automation is increasingly showing up on the radar of urban planning and transportation planning professionals. Technologies are developing rapidly, and some news stories report that fully self-driving cars are just a few years away. It’s tempting to envision automation ushering in a bold new era in urban transportation, where driverless cars whisk passengers between destinations safely and conveniently, use roads with great efficiency, and make public transit as we know it obsolete.
However, a closer look at vehicle automation reveals a more nuanced picture of the future. Automation capable of replacing human drivers in any situation may be many years away from the market. The traffic flow improvements enabled by automation will be limited in several ways. Buses and other forms of public transit will still be needed to efficiently move large numbers of travelers around cities. And various forms of automation in buses could enable major improvements in service.
The last two points have come up on this blog before (here, here and here), but since there are a variety of opinions on the implications of automation for transit, it’s useful to dig a bit deeper into these issues and take a critical look at when various forms of automation will arrive, how automation will affect traffic flow, and how it will affect travel behaviour. This post will delve into those questions to shed a bit more light on what automation means for the future of public transit.
According to some, vehicles that can drive themselves anywhere, anytime, without any human intervention – described as “Level 4” vehicles by the National Highway Traffic Safety Administration (NHTSA) – are just around the corner. In 2012, Google co-founder Sergey Brin said of their famous self-driving car: “you can count on one hand the number of years until ordinary people can experience this.” Many others have made bullish predictions. For example, the market research firm ABI Research foresees Level 4 cars on the roads by around 2020, and panelists at the Society of Automotive Engineers (SAE) 2013 World Congress predicted arrival between 2020 and 2025.
On the other hand, some point to a number of challenges that suggest Level 4 will emerge further down the road, perhaps not for several decades. Steven Shladover of the California Partners for Advanced Transportation Technology, a leading expert on vehicle automation, argues that Level 4 will be much more technically difficult to achieve than many optimists acknowledge (see Vol. 7, No. 3 here). According to Shladover, huge advances in technology would be needed to progress to systems capable of driving safely in the vast range of complex and unpredictable situations that arise on roads. In addition, such systems would have to be far more reliable than products like laptops or mobile phones, and extensive – and expensive – testing will be needed to prove reliability. While Google’s vehicles have driven long distances in testing – over 500,000 miles as of late 2013 – and have not caused any crashes while in automated mode, Shladover points out that this proves very little because their vehicles are monitored by drivers who take over when risky or challenging situations arise.
Legal and liability issues could also delay the emergence of Level 4 vehicles. A few American jurisdictions now explicitly allow automated vehicles on public roads for testing, and Bryant Walker Smith, a leading authority on the legal dimensions of vehicle automation, has found that automated vehicles are “probably” legal in the US; however, he also cautions that their adoption may be slowed by current laws. Laws will have to be clarified before Level 4 vehicles hit the mass market in the US and in other countries. Liability for crashes could also be a thorny question. If a human isn’t driving, presumably blame would shift to the manufacturer, or perhaps a supplier of system components, or a computer programmer. Resolving these issues could stall the emergence of automation.
While there is dispute as to when Level 4 vehicles will be on the road, most in the field agree that more limited forms of automation are coming soon. Some are already here. For example, Mercedes S-Class vehicles can simultaneously control speed and steering when road and traffic conditions allow, though the driver must continuously monitor the road. This is just shy of “Level 2” automation, since Mercedes’ system also requires the driver to keep their hands on the wheel. Numerous other vehicle manufacturers are developing advanced technologies that promise to take over driving duties, at least some of the time, on some roads. As technologies advance, “Level 3” vehicles could be on the market by 2020 to 2025, according to most experts. These vehicles would allow drivers to forget about monitoring the road and instead read or watch a movie, with the caveat that when the automated system is out of its depth, it would ask the driver to take over. (The takeover time is a matter of debate – anywhere from several seconds to several minutes has been suggested.)
Automation could be a boon for safety – or it could create new problems. On the plus side, it appears that crash avoidance systems already on the market may be effective. Of course, as machines take over more of the responsibility of driving, safety will only improve if the machines are in fact less fallible than humans. This might seem an easy task, considering the foibles of humans, but it’s worth remembering that some automation experts believe otherwise. And where driving is shared between human and machine, the safety impacts are especially open to question. A driver in a Level 2 vehicle might fail to continuously monitor the road, or a driver in a Level 3 vehicle could be engrossed in their movie and fail to take over control quickly enough when requested. In either case, automation could actually decrease safety.
After safety, one of the biggest selling points of vehicle automation is its potential for improving traffic flow, especially through increased road capacity. With their slow reaction times, human drivers can’t safely follow other vehicles closely, so even at maximum capacity, around 90 percent of the length of a freeway lane is empty. If machines could react quickly enough, road capacity would increase enormously. Some studies appear to suggest huge increases are in fact possible – for example, one study estimates that capacity would almost quadruple, and another finds quintupled capacity. However, their calculations consider endless streams of densely-packed vehicles. More realistic estimates assume that several vehicles, say four to twenty, would follow each other in tightly packed groups or “platoons”, with each group separated from the next by a large gap. These interplatoon gaps would provide safety and allow vehicles to change lanes and enter and exit the freeway. Studies that account for these gaps estimate that automation would increase capacity in the range of 50 to 100 percent (for examples, see here and here).
While the more realistic estimates of capacity increases are still very impressive, there are a number of caveats. First, short headways are possible only when automated vehicles are equipped with V2V, or vehicle-to-vehicle communication. Vehicles that rely completely on on-board sensors – such as the Google self-driving car, in its current form – cannot react quickly enough to the movements of other vehicles, so they would enable relatively small capacity increases. A second caveat: large capacity increases would come only when automated cars dominate the road. Studies have found that when fewer than 30 to 40 percent of vehicles on the road are capable of platooning, there would be little effect on capacity, and large increases would come only after the proportion of equipped vehicles exceeds 60 to 85 percent (e.g., see here). This is important, since new vehicle technologies will take some time to become commonplace. Imagine that as soon as automated vehicles hit the market, every new vehicle purchased is automated: it would then take two decades for automated vehicles to account for around 90 percent of vehicles on the road. If the rate of adoption is more realistic, but still rapid, it would take three decades or more before automated vehicles make possible large road capacity increases. A third major caveat: platooning is only feasible on freeways. Changing lanes, stopping at red lights, making left turns, parallel parking, stopping for pedestrians – such manoeuvres would make platooning impractical on city streets.
For city streets, however, there is the prospect of using automation to improve flows at intersections by coordinating vehicle movements. A good example is the “reservation-based” intersection, where there are no stop lights or stop signs – instead, cars equipped with V2I (vehicle-to-infrastructure communications) technology “call ahead” to a roadside computer that orchestrates the movements of vehicles and assigns time and space slots for vehicles to cross the intersection. Simulations show such an intersection could move almost as much vehicle traffic as an overpass – but so far, simulations haven’t included pedestrians and cyclists. Accommodating these road users in a reservation-based intersection would require signals with sufficiently long cycles, so capacity increases would be limited.
Vehicle automation would also bring a very direct impact: reduced or eliminated labour in driving. Time spent traveling in Level 2 vehicles could be less stressful, and could become more productive and enjoyable in Level 3 and especially in Level 4 vehicles. Profound changes in travel behaviour would result. As people increasingly let their robot chauffeurs deal with road congestion and other hassles of driving, travel by motor vehicle would become more attractive. Trips would tend to be longer and more frequent and travel at peak times would increase. Trip routes would also tend to make greater use of freeways with Level 2 and 3 vehicles, since it is primarily on these roads that the vehicles will be able to operate in automated mode.
These induced demand effects would tend to increase road congestion. Freeways would be the exception – if platooning-capable technology becomes widespread, freeway capacity would increase and congestion would drop. That is, until the surplus capacity is taken up by the “triple convergence” of mode shifts, route changes, and change of time of day of travel. However, the increase in freeway traffic would be constrained by capacity limitations on the rest of the road network – as freeway travel increases, new bottlenecks would form on streets near freeway entrances and exits, where automation does not boost capacity, thus restricting the volume of traffic that can access the freeway.
The upshot of the above observations on the capacity effects of automation is that even when the potential freeway capacity increases enabled by platooning are fully realized, automated cars would nevertheless be able to carry far fewer people than bus or rail on a given right-of-way. And, as mentioned, capacities on streets will be largely unaffected. Because the capacity improvements made possible by automation would be limited, we will still need buses and trains when space is in short supply and we need to transport large numbers of people. Larger vehicles will still fit a lot more people into a given length and width of right-of-way than platoons of small vehicles will be able to carry. As Jarrett would say, it’s a simple fact of geometry.
So, vehicle automation will not render large transit vehicles obsolete. On the contrary, it could enable significant improvements in bus service and increases in ridership. Automated steering enables bus operation at speed in narrow busways, which reduces infrastructure and land costs. It also enables precise docking at passenger platforms, which improves passenger accessibility and reduces dwell times. Automated control of speed enables bus platooning, allowing buses to effectively act like trains. Automation can be taken further yet: a driver in a lead bus can lead a platoon of driverless buses, thus providing high capacity with low labour costs. Similarly, individual buses or platoons can operate driverlessly, thus enabling increased frequency with low labour costs. “Dual mode” operation is also possible: imagine a busway where chains of buses leave the city running like a train until they separate at a suburban station, where drivers board and take them onward onto various local routings.
Some of these forms of automation have already been implemented in BRT systems. For example, a system in Las Vegas employed optical sensors to enable precise docking at passenger platforms, BRT buses in Eugene, Oregon used magnetic guidance to facilitate precision docking and lane-keeping in a pilot project, and systems in Paris and Rouen, France, and in Eindhoven, the Netherlands, use various types of guidance systems. While bus platooning and driverless operation have not been deployed so far, these applications could be achieved given sufficient technological advances – or by using a low-tech shortcut. The simple solution is to keep other vehicles or humans out of the way of the automated bus. If buses operate on busways with adequate protection, platooning and driverless operation is possible with existing technology. (Similarly, current driverless train systems are able to operate driverlessly, even with decades-old technology, by virtue of the well-protected guideways they run on.) Developing a vehicle capable of driving itself in the simplified environment of a protected busway is a considerably easier task than developing a vehicle that can drive itself on any road, anytime.
With the arrival of Level 4 automation, driverless buses could operate on the general road network. This would make it possible to operate smaller buses at higher frequencies, since labour costs would no longer constrain frequency. If you shrink driverless buses small enough – and provide demand-responsive service for individual travelers – you end up with driverless taxis. This points to the possibility that public transit service may be more efficiently provided by driverless taxis (or driverless share taxis) in low-density areas, thereby replacing the most unproductive bus services and improving transit productivity overall. (Of course, while automation could boost productivity, even driverless demand-responsive service would still have low productivity where densities are low.)
While it’s a seductive story that driverless cars will transport us to a realm of much improved safety, convenience, and efficient road use – and where public transit has dwindled away – the future is likely to be more complicated. Advanced automation is indeed coming soon, though we might not see Level 4 technologies for a while. Automation could improve safety, though it could also generate new problems. It could also improve road capacity, but the improvements would be limited in several ways. All this suggests that we needn’t worry about (or celebrate) how vehicle automation will make public transit obsolete. Instead, let’s focus on how to use automation to the advantage of public transit.
The increasing prevalence of mobile communications technologies has important consequences for urban transportation. The new ability to carry your social life around with you, enabling instant connections regardless of physical location, has the potential to reconfigure how we think about time and mobility, and in turn how we build environments to suit our travel behavior. For example, it appears to be impossible to use smartphones safely while driving, so smartphone users have a motive to seek an alternative mode so that they can make use of their travel time.
Ben Schulman has an interesting take on this in his paper, The Car as Smartphone: Effects on the Built Environment and Sociality, which you can download below. He places the smartphone in a continuity of change in human communications technology, and traces how those technologies have helped to shape our cities.
The built environment then is a reflection of the predominant communication devices being used at given points in time that shape sociality. In other words, we develop an infrastructure necessary to accommodate the needs of our preferred communication tools.
This idea is a larger envelope around the familiar idea that all cities are built around the transportation technologies of the time. Transportation, after all, is one kind of communication tool.
There is a lot of to digest here, but it is well worth a read in order to situate these trends within an academic urbanist frame of reference. My take is that the role of communication is hugely important, but must be understood as an aspect of a broader web of economic and social relationships which together work to produce the space of the city.
Over the last 15 years, the Internet and mobile communications technologies have transformed the way Americans live and work. During that same period, growth in [motor] vehicle travel slowed and then stopped, with Americans today driving about as much on average as we did in 1996.
USPIRG has a new report out today, focused on how network technology has ushered in new possibilities for Americans' personal mobility. Modern communications are beginning to alter the types of trips people need to make, as more and more people work remotely for at least a portion of their working hours. The mobile, high-speed, GPS devices that a majority now own are absolutely necessary to the cellphone trip planners and various -sharing systems that have spread to many US cities in recent years.
This is one of the most compelling arguments for why we should expect America's declining interest in cars to be permanent.
The "decline of cars" story is a hard one to convey to the currently ruling generation (now in their 40s-70s). Older folks too easily assume that Millennial disinterest in cars has something to do with being young and single and childless and maybe poor.
We already knew that Americans are getting drivers licenses later and later in life -- and this statistic ought to get attention because it's comparing Millennial behavior to that of their parents at the same age.
The strongest story, though, presents not just a trend but an explanation of it, and that's what we have here. Communications technology explains why the younger generation is finding cars less necessary (and why older people who are good at technological uptake are finding the same thing). People still need to be together (see Yahoo's recent decision to abolish telecommuting) but communication technology is replacing a lot of errands that the older generation is used to doing with cars.
USPIRG reviews a broad array of recent research on the topic, concluding:
By providing more choices and flexibility for individuals to meet their transportation needs, these new tools can make it convenient to adopt “carfree” and “car-light” lifestyles.
Households that reduce the number of vehicles they own often dramatically reduce the number of miles they drive. Because many of the costs of owning a car are perceived to be fixed, vehicle owners perceive the cost of driving an additional mile to be artificially low. New services such as carsharing shift the cost of driving from fixed to per-mile costs, providing an incentive for users to drive less and allowing many households to reduce their overall spending on transportation.
Information technologies make it easier to ensure seamless connections between various modes of transportation, expanding the number and types of trips that can be completed effectively without a car.
The report also discusses mobile ticketing, perception of travel time, and each of the various sorts of sharing services, and provides a set of policy recommendations to respond to and build upon the potential of this technology. Read it yourself here.
Are you sure that rail "stimulates development" and that buses don't? In a major report released today, the Institution for Transportation and Development Policy (ITDP) attacks this assumption head-on.
Per dollar of transit investment, and under similar conditions, Bus Rapid Transit leverages more transit-oriented development investment than Light Rail Transit or streetcars.
What really matters to transit-oriented development [TOD] outcomes? According to the report, the #1 predictor is strong government support for redevelopment, while the #2 predictor is real estate market conditions. The #3 predictor is the usefulness of the transit services -- frequency, speed, and reliability as ensured by an exclusive right of way. Using rail vs bus technologies does not appear to matter much at all.
While BRT is is having overwhelming success across the developing world, ITDP's argument is aimed at North America, so it rests on North American examples. Cleveland's HealthLine, a practical urban BRT linking two of the city's strongest destinations, emerges as a great urban redevelopment success story as well as the overall highest-quality BRT service in the US. Las Vegas, Ottawa, Eugene, and Pittsburgh's eastern line all play key roles in the argument. Las Vegas, whose busway is incomplete but is in exactly the right place to serve heavy demand, is one of the most interesting stories, where BRT is playing a key role in the remarkable pedestrianization of what used to be one of the most famous car-only landscapes in the world.
There will be plenty of quarrel over the details. But this report does represent a "coming out" for the very concept of bus-based transit oriented development. For too long, the identification of "transit oriented development" (TOD) with rail has bordered on tautological: if there wasn't rail, it was less likely to be called a TOD, no matter how useful the bus service was. In fact, almost everything that's been built in every North American inner city has been TOD in the sense that bus service -- usually of high quantity if not high quality -- has been intrinsic to the neighborhood's appeal and functioning.
This is not to say that I agree with ITDP's anti-rail view. I support many exclusive-right-of-way light rail projects, and I am not anti-rail except to the extent that rail partisans insist on being anti-bus. In most North American cities, if you're ideologically anti-bus, then you are hostile to most of your city's transit system, and to most of what transit can practically achieve in the near future at the scale of the whole city. Great transit networks are those where all the modes work together to maximize everyone's liberty. All claims for the hegemony of one mode over another are distractions from creating the most effective transit for a city as a whole.
But technology wars meet so many human needs that they will always be with us, and so given that it's best they be as balanced as possible. Bravo to ITDP for having the courage to speak up about the redevelopment value of highly useful and liberating transit services, regardless of what's going on under the floor.
The Sydney Monorail, built in imitation of Seattle's, has now been through the predictable phases of exuberance, delight, irritation, and boredom, and has finally arrived at the point of being more of an obstacle than a service. The Sydney Morning Herald interviews longtime monorail fan Michael Sweeney who says what little can be said in the thing's defense. He even uses the word groovy, reminding us (and the interviewer) that he's expressing a definition of coolness that prevailed in one historical moment. There was never any reason to assume the monorail would be cool forever.
Why? The usual things. It was conceived as part of a redevelopment, designed to be part of the excitement that would sell expensive real estate. Like many new North American streetcars, the point was solely to achieve a development outcome and nobody much cared whether it would be useful as transit, especially decades into the future.
It was a tiny one-way loop, only about 1 km in diameter, connecting some key tourist destinations into downtown. Even for tourists it had limited use because -- like most North American streetcars again -- the route was so short that you might as well walk, as most people do in this area.
As urban design, the monorail wasn't that bothersome when it sailed over the open spaces of Darling Harbour, but when it snaked through the narrow streets of the CBD, it was a heavy weight in the air on narrow streets that were already oppressive to the pedestrian.
It's not surprising that it took a new redevelopment plan to sweep away the toys of the old. Still, the calculus came down to this: It's not very useful. If you want to get somewhere on the loop, and back, you might as well walk. And there are far fewer people riding it than walking under it, perceiving it as an oppressive weight.
So it's coming down. Last ride is this Sunday.
This just in from the BBC: Technology giant Philips corporation sent some people to the extremely busy Singapore bus system to imagine an alternative to typical fixed-route bus service. The researchers' definition of the problem:
We discussed the benefits and limitations of the fixed-route system – it's clear such a system provided consistency in time and place (to get on and off), and to a certain extent convenience, but not completely. Flexibility is not what a fixed-route and fixed-time bus service system can offer. We have all experienced times when the bus is very empty or extremely packed, which means efficiency is best optimised at the bus-route level, but not individual bus level, since that bus is unable to respond to dynamic demand and traffic situations immediately. We all have all been in situations when there are only a few passengers in the bus and yet, the bus still has to plough through the entire fixed route, picking up no passengers along the way. The motivation was how to optimise the bus service by allowing the passengers and bus drivers to respond immediately to dynamic demand and traffic situations, not unlike a taxi that you can flag anywhere, anytime, and it will take you directly to your destination.
Needless to say, they came up with a massively all-demand-reponsive system identical to the one promoted last year by Gensler Associates, to which I responded (perhaps too colorfully) here. The idea is that now that you have a smartphone, the transit line should twist and turn to meet chase everyone's speciic need and that somehow this will be more efficient. As I said in response to Gensler, there's little to fear from this dystopian vision beause it's mathematically impossible.
In a place as crowded as Singapore, well-designed scheduled fixed routes are not just efficient but liberating. They're efficient on a large scale despite routine under- and overcrowding because they follow straight paths that thousands of people find useful at the same time. They're efficient because people gather at major stops where they board and alight in large numbers that are impossible in any demand-responsive form. Frequent fixed routes are liberating because they're there for you when you need them, just as subways are, so that you don't have to wonder whether some automated system will approve your request for transport.
The all-demand-responsive vision can mean one of two things: (1) large buses that carry large numbers of people on complex variable routes, changing its route in response to every beep of desire from each of 5 million phones, or (2) fleets of very small vehicles each serving a few people on a more direct path. Vision (1) is a hellishly circuitous system to ride any distance on, while (2) is a vision of vastly more wasteful use of urban space, as people who are now carried in a space-efficient way are converted to a space-wasteful one. Vision (2) also requires either driverless technology or extremely cheap labor, which is why it only happens at scale in low-wage developing countries.
No, Singapore has built its success on subways, and is developing fixed, infrastructural bus lines that work more like subways.
[Thomas Edison] has so far perfected his storage battery that it will live long enough to stand charges to carry a truck over fifty thousand miles. The perfected battery will pull twice the load of an ordinary truck, will have double the speed and only take up half the space. It will modify, to an extent hardly appreciated, the congestion of the down-town streets, for an electric truck equipped with the batteries will be half as long as today's unwieldy wagons. Being twice as fast, there will be only one eighth of the present congestion in the streets under the new system of speedy motor trucks.
From a fascinating article about Thomas Edison
in Success magazine, 1908, by Robert D. Heil.
The whole article is a delightful read!
This makes so many important points!
Obviously, stuff gets invented that changes things, but when technology claims to fix a physics problem, such as seems to underlie the challenge of mobile batteries, or a problem of supply and demand, like the role of induced demand in congestion, be skeptical.
Hat tip: @enf, (Eric Fischer)
Richard Gilbert, co-author of a book that I've praised called Transport Revolutions, has a Globe and Mail series arguing for how driverless cars will change everything. Although it comes with a picture of typical "Personal Rapid Transit" "pod cars" on a separated guideway, Gilbert tells us he is shifting his focus to driverless cars that would run on ordinary streets at far less infrastructure cost.
I will give this series a more thorough read, but just want to call out one key rhetorical move that needs to be noticed in all these discussions. It's in the beginning of Part 4, "Why driverless cars will trump transit rivals."
With widespread use of driverless cars – mostly as autonomous taxicabs (ATs) – there could be more vehicles on the road because ATs will substitute for most, and perhaps eventually all, private automobile use as well as much use of buses and other conventional transit.
This, and much of the discussion around driverless cars, is in the complete imagined future mode. Gilbert describes a world in which the driverless cars are already the dominant mode, and where our cities, infrastructure, and cultural expectations have already been reorganized around their potential and needs.
Some complete imagined futures are not necessarily achievable, because the future must be evolved. In fact, the evolution of organisms is a fairly apt metaphor for how cities and infrastructure change. As in evolution, each incremental state in the transformation to the new reality must itself be a viable system. We can think of lots of wonderful futures that would be internally consistent but for which there is no credible path from here to there.
Driverless cars remind me a bit of the "wheeled animal" question in evolution. No animals have evolved with wheels, despite the splendid advantages that wheels might confer on open ground. That's because there's no credible intermediate state where some part of an animal has mutated something vaguely wheel-like that incrementally improves its locomotion to the point of conferring an advantage. Wheels (and axles) have to exist completely before they are useful at all, which is why wheeled animals, if they existed, would be an argument for "intelligent design."
I will begin to take driverless cars seriously when I see credible narratives about all the intermediate states of their evolution, and how each will be an improvement that is both technically and culturally embraced. How will driverless and conventional cars mix in roads where the needs of conventional cars still dominate the politics of road design? How will they come to triumph in this situation? How does the driverless taxi business model work before the taxis are abundant? Some of the questions seem menial but really are profound: When a driverless car is at fault in the accident, to what human being does that fault attach? The programmer? What degree of perfection is needed for software that will be trusted to protect not just the passengers, but everyone on the street who is involuntarily in the presence of such a machine?
Here's a practical example: In Part 3, Gilbert tells us that with narrower driverless cars, "three vehicles will fit across two lanes." Presumably lanes will someday be restriped to match this reality, but when you do that, how do existing-width cars adapt? If you could fit two driverless cars into one existing lane, you could imagine driverless cars fitting into existing lanes side by side, so that the street could gradually evolve from, say, two wide lanes to four narrow ones. But converting two lanes to three narrow ones is much trickier. I'd like to see how each stage in the evolution is supposed to work, both technically and culturally.
That's one reason that I seem unable to join the driverless car bandwagon just yet. The other is that claims for driverless taxis replacing transit amount to imaging a completed new technology out-competing an existing unimproved technology -- as though that would actually happen.
Sure, driverless taxis might replace many lower-ridership bus lines, but wouldn't buses become driverless at the same time? In such a future, wouldn't any fair pricing make these driverless buses much cheaper to use where volumes are high? Wouldn't there be a future of shared vehicles of various sizes, many engaged in what we would recognize as public transit? As with all things PRT, I notice a frequent slipperiness in explanations of it; I'm not sure, at each moment, whether we're talking about something that prevents you from having to ride with strangers (the core pitch of "Personal" rapid transit) as opposed to just a more efficient means of providing public transit, i.e. a service that welcomes the need to ride with strangers as the key to its efficient use of both money and space.
Feel free to enlighten me if I'm missing something here!