Future with driverless cars 2: Mass Transportation

This is part two of a series on changes that driverless cars may bring. I expose some of the ideas I have, mostly quite practical things. We moved project troglodyte to it’s own website, so the more patent centric recap of the Google driverless car patents can be found from there.

Below I assume that the problem has been solved completely. Driverless cars can access any part of the road network, function even when there are people darting around and can handle any weather including lots of snow and very slippery conditions. Accident levels are same or lower than currently and people are not scared to use autonomous cars.

See also: Rental vs. taxi, Mass transportation, Pirvate cars, Cargo, Parking and driving empty, Zoning Traffic volume and Externalities

Just like the difference between rental cars and taxis will dissolve, mass transportation will also overlap more with taxis. This is because currently cost of drivers pushes public transportation towards larger vehicles and less frequent service. The larger the vehicle is, the smaller the change in cost structure as personnel costs become less important in trams and trains due to their larger passenger capacity. Smaller busses and more frequent operation will become a practical proposition.

While taxi traffic probably also scales nonlinearly this is certainly true for public transportation. More people travelling leads to more frequent operation, it will be easier to change between lines, journey times will be shorter and prices will be lower. This would seem to indicate that busses would benefit greatly from being able to operate autonomously. The optimum transition point between operating a bus or a tram/light rail would also likely be different. With current arrangements it is difficult to operate busses with very short intervals, as this leads to busses travelling right behind each other with some full and others empty. With smaller busses it would be possible to operate slightly different parallel routes if the geography of the area allows it. In many cases this is not possible and it would still be necessary to use a higher capacity transport mode.

Currently there seems to be a psychological limit for the minimum size of public transport, people don’t want to get into a small vehicle with strangers. There are some fully automated rail systems in operation and in many trains the operator is not able to intervene to assist if there is some trouble, so this doesn’t seem to be a big problem for large vehicles, but it can be a limiting factor for smaller ones.

Passenger density is larger for big vehicles and the possibility of some passengers standing during rush hour gives some flexibility in exchange to some discomfort. A large vehicle can also have large doors enabling fast boarding, this is an important factor for high throughput mass transportation with many stops. For very small vehicles the same road or rail network would still be able to handle less passengers despite the smaller headway enabled by the automation of the vehicles.

Vehicle costs also differ between small and large vehicles, small ones can be mass produced with fairly low cost, while larger ones likely have lower maintenance costs per capacity. Small vehicles can idle when not needed, but large ones need to run half empty during off peak hours. Most likely different solutions will be used in different environments to optimized between the comfort of small, even one person vehicles and the higher capacity of larger ones.

Acknowledgment:  Thanks to Laston Kirkland for thoughtful evaluation of these ideas.

2 thoughts on “Future with driverless cars 2: Mass Transportation”

  1. I’m really enjoying this articles as an unbound enthusiast for the autonomous car technology.
    As I imagine the reality of public transportation and traffic in general to be quite different on your surroundings, I believe I have a different view of this issues. Being from a big metropolis that grew without the proper traffic planning and poor maintenance (I’m from São Paulo, Brazil) I felt the urge to share some new points and problems into this solution:
    1- More vehicles would demand greater maintenance and better logistic structures, regardless of their size. That implies greater costs and other demands, such as more qualified personnel. It would take longer to implement that.
    2- All places I know of still need a way of charging for each use of a bus. Having no driver would still not cut out the need of a collector, which many times is necessary to be present and apparent to enforce paying. I would still see this employee as a basic need for vehicle and passengers safety.
    3- I believe autonomous vehicles would allow new design, that may save space and allow more seats per bus. Not only would the drivers seat space be freed. A city with greater autonomous than driven vehicles traffic would allow more flexibility with the shape and size of buses. Same would come from having many less cars parked along the curb.

    I hope we’ll see the day when people will retire and get rid of their private cars to use only autonomous rentals everywhere! I truly think that is the future!

    1. Thanks for the comment :)

      Here my views on your points:
      1. It is true that when the number of vechicles is larger there are likely more potential parts that can brake down. But when the number of vehicles is large there is also a larger imperative to test the vehicles well before going to production. It should also be noted that any one unit is responsible for less of the total transportation need, so the system becomes more predictable, you need less investement in spare vehicles.

      2. As far as I can tell there are very few workers just selling tickects in buses, trams or even local trains in Europe. In many places it is possible to use any door to enter the vehicle and pay by card that is placed close to a reader. Enforcement is done by personnell randomly entering vehicles and chekcing that everyone has paid. If not there is a small “fine”.

      3. I agree.

Comments are closed.