The 2-wheel PRT route network

Network Structure

Underpass for completely grade-free operation

Route protection with fences and boom barriers

Restricted mixed traffic

Unrestricted mixed traffic

(click onto the images for enlarging)

• Roadway:
  • paved lane width: 0,5 m [1,6 ft]
  • spacing between lanes: 1,5 m [4,9 ft]
  • possibly fences necessary to avoid collisions with animals

• back-bones:
  • full grade separation
  • 80 km/h [50 mph] continuously

• feeders:
  • serving only for last/first mile, connections between individual villages consistently via backbones
  • partly low speed (30 km/h [19 mph] in built-up areas, at junctions even less)
  • offline stations: vehicles stopping in the rental station can be bypassed

  • Several variants within built-up areas (compromise between safety, reliability and practicability):
    1. complete separation: all roads crossed by underpasses, between them route protected by fences from any interaction with pedestrians, vehicles etc.. Providing maximum safety and most reliable travel time, but requires highest construction costs and divides neighborhoods by fences.
    2. traffic lights & boom barriers instead of underpasses: Particularly minor road crossings are realized with traffic lights, additionally protected with boom barriers (barriers similar to those of railway crossings, but connected to conventional road-style traffic lights instead of general priority for 2-wheel PRT). Providing virtually the same level of safety as the complete separation, but travel times are a little longer and less reliable because of waiting times at traffic lights.
    3. No physical barriers against pedestrians: between road crossings, there are no fences or other physical barriers, some residual risk of collisions with pedestrians at low speed is accepted.
    4. restricted mixed traffic: use of existing road infrastructure, but operation of the vehicles is limited to defined routes, which may be modified to increase safety or reduce complexity (e.g. lower speed limit, modification of road intersections, navigation marks for 2-wheel PRT...)
    5. unrestricted mixed traffic: every existing road within built-up areas resp. with according speed limit can be used without modification (direct access to any address within the villages connected to the 2-wheel PRT network, no walking distance to the next rental station). Although it is the least safe of all the variants conceived, the 2-wheel-PRT users should not be more threatened than a cyclist, riding through a village in mixed traffic at similar speed without any elements of passive safety.

    First applications could start at a higher safety level and after experience from them and some improvements in self-steering technology, further development could lead to the cheaper and more flexible variants.