An interesting article on Citylab highlights something I’ve been saying for a while when it comes to the hype around driverless cars – what about the pedestrians. It’s based of the video (below) from MIT’s Senseable City Lab showing how an urban intersection might work in a world of driverless cars.

Imagine a city without traffic lights, where lanes of cars merge harmoniously from one to the next, allowing traffic to flow smoothly across intersections. This futuristic vision is becoming reality. The development of autonomous driving promises to revolutionise the landscape of urban mobility.

As Citylab note:

The first thing to notice is how truly terrifying it would be—at least initially—to ride in a driverless car going that fast through an intersection. Seriously: pause the video at 44 seconds and see how narrowly the car turning left avoids being slammed by another going straight. When you ride in a self-driving car, you quickly learn to trust it; in fact, Google has said its early test riders trusted the car too much on highways. But having faith in a computerized intersection overlord to orchestrate so much city traffic at such great speeds will require a steep period of public adjustment.

The second thing to note is far more important: Where are all the pedestrians and bike riders? (Hat tip to Columbia University planning professor David King for bringing this to our attention.) Keep in mind this wasn’t some remote crossing being modeled; it was the intersection of Massachusetts and Columbus avenues in Boston.

There’s an obvious reason why an “intelligent intersection” would want to eliminate people crossing on foot or by bike: they’d slow things down. But it would be a huge mistake for cities to undo all the progress being made on human-scale street design just to accommodate a perfect algorithm of car movement. If the result is that driverless cars need to move through cities at sub-optimal speeds, then so be it. We won’t be losing as much productivity to traffic as we do today, anyway.

So yes driverless cars might improve vehicle throughput a bit over what we have now but almost certainly not as much as the claims made by many about the technology unless we take the retrograde step of marginalising pedestrians (and cyclists).

I must say I hadn’t thought about the issue of how it would feel being in a driverless car and going through an intersection and seeing another car approach at speed from a different direction. That would definitely take some time to get used to and would be very scary if you were on a bike.

All up it just adds to my view that while driverless vehicles are coming, they won’t be here as soon or have as big an impact as some people claim. In the mean time we will likely continue to see aspects of autonomy increasing such as technology that helps improve safety or assist with parking.

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  1. Given the three laws of robotics, the first law ensures humans walking and on bikes will be able to walk through the intersection and cars will need to stop for them. The passenger will not be able to order the robot to drive through the intersection without stopping for the humans, as this would be in conflict with the second law. The world will become a paradise like Vancouver, where if you are standing on the footpath looking like you want to cross, vehicles just stop for you (It’s a really weird experience at first).

    1. A robot may not injure a human being or, through inaction, allow a human being to come to harm.
    2. A robot must obey orders given it by human beings except where such orders would conflict with the First Law.
    3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law.

    1. Couple of problems:

      1. Cyclists and Peds ain’t humans in the definition of most drivers 🙂
      2. Those laws are a “serving suggestion” written by Mr Asimov decades ago for how good robots would be programmed to act – they’re not a legal requirement in any jurisdiction -otherwise how come automated US Drones can shoot humans on the ground without breaking at least 1 of the laws? Rule 2 springs to mind here

      1. It is likely that a drive less car will be programmed to not collide with anything, full stop. the car won’t care whether the object is a person another car or a power pole. it will take action to avoid the collision and come to a complete stop if necessary. Thus the car won’t speed through an intersection or along a road if there are pedestrians or cyclists around, they will have to at least slow down, and will often need to stop. There will probably be a pre-determined maximum speed at which the car will be allowed to pass a cyclist. there will be a minimum berth space, if insufficient room the car will drive behind the cyclist until there is sufficient space to pass. if a pedestrian decides to cross a road then the car will likely have to come to a complete stop to avoid hitting the pedestrian and any other cars on the road. Given that the car will need to be able stop in time this also will put an upper limit on the speed it can travel.

        1. And when the inevitable happens and it HAS to hit something through no fault of its own?
          How will it know which is the least valuable thing to hit in that situation?

          For sure I’d prefer the car wrap itself around a light pole and not hit some people than vice versa because the programmer who programmed it simply said, well all objects on the road are equal priority i.e. they’re all the same – so the car hits whatever it hits.

          Sound like dumb programming of the worst sort in that case.

        2. Unpleasant thought I just had: cars will be programmed to avoid obstacles, but will they be programmed to give enough space to people walking/biking? Or will the computers send the cars whizzing past six inches from our right elbows, leaving heart attacks in their wake?

  2. but only when ALL cars can be guaranteed to be driverless, will driving as an activity be banned?

    given the closeness of passing, how will a driverless car cope with the indecision of many pedestrians at crossings?

  3. I was in Hanoi last month and this was my first experience of traffic chaos however it seems to work. Very scary the first time crossing the busy roads however like a school of fish they just go around you and after a few days you get use to it. The key to it is to walk without hesitation and the traffic just avoids you. Driverless cars will do the same.

    1. Only if the driverless cars travel as slowly as Vietnamese traffic. (Worth noting that Vietnam has one of the worst road fatality rates in the world BTW.)

    2. I’ve crossed that intersection too. You just have to breathe deep and walk out in a steady line. However don’t make the rookie mistake. Bikes and motos will go around you, cars will stop… but buses and trucks do not!

  4. I cant say I agree with the citylabs appraisal.

    Driverless vehicles will impact the world in several different ways, only one of which is actually to do with increased efficiency in terms of use of road space. And should this efficiency comes to pass, there is no reason it wont be “reinvested” in better outcomes for peds and cyclists. To take the example in the video, more efficient intersections could be phased to be “all red” for the cars 70% of the time with autonomous cars “efficiently” using the intersection 30% of the time. Additionally increased efficiency could lead to less road space being allocated to vehicles.

    But in terms of impact, to me the most important aspect will be around car ownership vs car use. Drverless cars will become public transport, complementing or superseding existing public transport. The flexibility of having a car when you need it, and not when you dont will be very important. This flexibility will be reinforced by the financial incentives – cars are currently close to “all you can eat” when you buy your own car and then pay an annual fee for insurance, registration etc. So incentives are skewed to maximising use. Driverless cars will change all that. Safety will of course be another major advantage and (direct) increased road space efficiency will be an impact that will be less important and will turn up later than the other impacts.

    1. Driverless cars aren’t likely to be more expensive than todays cars, why wouldn’t a family own 3 or 4 or 5 of them? One for mum, one for dad, one for each of the kids and a big car for the weekends. The kids could drive themselves to school and off to their friends. The driverless car offers the auto industry a massive opportunity to gain new customers, we could easily see the car market expand by 30 – 50 %.

      1. Because, no need. Cars are expensive. People try to minimise the cost of transportation, or anything, for a given quantity of it. People own cars because it is currently the most cost effective way of meeting their transportation needs. That wont be necessary with driverless cars – no driver to pay.

        1. great. The next person can clean the car after I have bought my wet sandy dog back from the beach.

      2. Just the parking space needed alone will kill this idea. If you have kids you have better uses for that space. Like, you know, a back yard where the kids can play.

        1. Kids that play outside? Wow. Most kids I know of these days are glued to screens in their bedrooms on their latest technologies.

        2. Yes, and for a start, we should give them at least a choice to get out. Can they go to their friends house without asking their parents to drive them around? Can they go to a park? Can they go to school?

    2. But in terms of impact, to me the most important aspect will be around car ownership vs car use. Drverless cars will become public transport, complementing or superseding existing public transport. The flexibility of having a car when you need it, and not when you dont will be very important.

      I don’t think that driverless cars will replace PT as there is still the issue of capacity and even if they do improve things some what, it will be no where near the level needed for cities to be successful – even Auckland. I can see them being a really useful last mile tool though

      1. Agreed, I wasn’t meaning to say that all fixed route PT would be replaced by “on demand” driverless vehicles, just possibly some niches.

  5. Perhaps the reason why pedestrians haven’t been thought about is that at the moment it is in the “too hard” basket? How do you account for irrational and unpredictive pedestrian behaviour? They don’t always try and cross a road when and where they are supossed to. if a driveless car has to be constantly looking out for all pedestrians on the footpath in case one of them suddenly decides to step onto the road it is doubful that the car will be able to navigate city streets any faster than cars do today. In fact because of safety they will probably travel slower. On the other hand city streets will become a lot safer for pedestrians, and that wouldn’t be a bad thing.

  6. Well it certainly looks like driverless could work well in the vehicle-only environments of motorways, but would grind to a complete and catatonic halt in the more random environments of peopled city streets.

    So will that add up to any sort of improvement? Yes if it means a big reduction in crashes where they can work, but not really if they can’t actually get anyone anywhere but up and down motorways… Perhaps all these vehicles will have to stop in huge parking garages at the off ramps and then people will have to walk, cycle, or, use some sort of collective movement machines to circulate on or under city streets… we could call these buses, trams, or The Metro….?

    1. And then when the city grinds to a halt due to pedestrians holding cars up, there will be the inevitable call for controls over pedestrians.

    2. All cyclists will need to be on fully-automatic self-steering, self-balancing electric bikes, and all pedestrians on autonomous Segways.

  7. Driverless cars = Drive Less Cars = Drive Cars Less = Stop building moar roads NOW.

    Simon Bridges is staking his reputation on driverless cars taking over some time soon. How do we get him to see the above logic?

    1. The way I see it driverless cars will increase the total km’s covered by the vehicle fleet.

      For example say I take my current car to work I can pay $10 to park 5 mins walk away, or $14 to part 2 mins walk away. If I had a driver-less car I would send it home to park for free in the garage I have already paid for, 2km of running costs is cheaper than parking. (actually I bike)

      Driverless cars will mean that those who cannot drive (kids, Vision/motor impaired (incl old people) and those without licences), will now be able to travel cheaply, so will be on the road for the first time without having to ask/pay somebody to drive for them.

      And my favourite: “I hear and awesome restaurant has opened in Hamilton… Lets go tonight, we’ll take my driver less car, and watch a movie on the way.”

      1. But the idea is that fewer people will bother *owning* cars. There will effectively be a pool of driverless taxis circulating from one person’s hire to the next, and so once you have been whisked to work in your driverless transport, it will then take off by itself to service someone else’s request in the near vicinity. So fewer vehicles working more-intensively will replace many that spend most of their day parked-up. At least that’s one projected scenario.

        And oh. . . .please remember to take all your belongings when you get out, and leave the vehicle in a condition that you would like to find it yourself. No popcorn scrunched into the carpet after watching that movie! (Besides, you wouln’t want to spoil your appetite for that awesome restaurant).

        And oh again. . . .Driverless cars might need to carry a government obesity warning since you won’t even get to exercise your accelerator-foot or your steering-wheel-muscles. Definitely should cut out that popcorn.

  8. Having spent time working in most Asian cities, including Vietnam, Thailand and India to name some of the scariest – I can also attest that pedestrians, cars and cyclists pass within millimetres of each other on roundabouts and crossings mostly very safely and it all seems to work. So driverless cars that pass within inches of a ped or cyclists won’t frighten too many people in those countries.

    On the subject of vehicle technology, a number of new cars now auto brake for obstacles and stay in lanes (Mercs, Audis, and others), no futuristic sci fi here, this tech will be common on most cheaper cars within 5 years I suspect.

    1. Yet nevertheless they have horrific injury and death rates, several times what ours are per capita (and there are a lot more people in those places!). Having spent time in those three countries I can attest to seeing pedestrian and traffic injuries daily. It all seems to work, until it doesn’t.

    2. @ Ricardo
      Not so sure I like your vision of a Vietnamese-style future transport system here in NZ. Speaking as a pedestrian and a cyclist that is.
      I’d prefer the Dutch approach thanks.

    3. So Ricardo I guess you’re one of those people who wouldn’t mind having 1000 road deaths per year, instead of the paltry 350 we have at the moment?

      As a car driver I’m not looking forward to this approach either.

      1. Not my vision of utopia, just pointing out the technology that is currently available and also mentioning that driverless cars in some parts of the world will not be the shock that it might be to the west. Why such overreaction?

        1. The situation of cars been close to people in some countries is with the car and motorbikes been driven by people. They are reacting to a number of factors that computers may not yet know how to do. For example does a Vietnamese scooter driver give a European pedestrian a wider berth? I would not be surprised if they did. This could be out of curtesy but also the fact they do not want to fall off their motor bike because a foreigner will cross the road “wrongly” Can computers do this in rainy conditions? I also wonder how a computer would handle the speed bump outside my place which is used by people to cross? Drivers react differently based on whether I approach, one of my kids on a manual scooter or an elderly person from the retirement flats. Can computers to this?

  9. Right now we have semi-autonomous cars for highway driving, but they are still pretty expensive. Lets say truly driverless cars become a reality in 10 years (Google still has a long way to go). I would expect it to be 10 years after that before they are trusted by the general populace and another 20 years after that before they make up the majority of vehicles on the roads. Traffic lights will exist for several decades until all the boomers who want to keep their antique cars on the road are dead. As long as there are “dumb cars” with dumb drivers we will need to have traffic lights. Which means pedestrians will be fine. And at uncontrolled crossings they will be safer. If you walk out in front of the car it will stop. Hopefully. I just think it will not happen as quickly as we think.

    1. Haha. As a boomer I hope I live long enough to see the end of the car-overdependent society. I hope I will have enough agility left in my bones to make use of all the new rail services we will have by then, and to walk and cycle safely on streets reclaimed from the dark-ages of automotive dominance!

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