Shape Morphing of Intersection Layouts Using Curb Side Oriented Driver Simulation

In a traffic network, capacities of parts of the network restrict the amount of transport that can be handled by this network. The capacity of a given traffic network element is not fixed, but influenced by parameters such as number of lanes, maximum speed, weather, view horizon, and so on. These parameters also define the maximum capacity of complicated intersections. Special shapes of intersections, particularly in urban regions, may further increase or decrease their capacity. This paper investigates an evolutionary algorithm to automatically improve the geometrical layout of parts of an urban network according to externally specified criteria. The paper consists of two main parts. In the first part, a simulation model is described which is able to produce realistically behaving vehicles only by using information about the curb side locations of the roads. This avoids the need to use lane connectivity, signal plans, etc. - which are details that would change during a change of the intersection layout. In the second part of the paper, the simulation changes the road and intersection layouts based on the behaviour of the vehicles. Using a feedback loop allows one to optimize the capacity of the modelled road system while its spatial extents are minimized. As a case study, a special roundabout is examined:'Central'in downtown Zurich, Switzerland. The particularity of this roundabout is that it partially behaves like a roundabout but also contains two uncontrolled intersections. Due to its central position in the city, the roundabout is very busy with both individual cars and public transport vehicles