toruseo/UXsim

Future Plan: multi-lane link

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The current model assumes that all links are 1 lane. Furthermore, the reaction time of all drivers are the same. These mean that all links have more or less the same capacity. It is not possible to model multi-lane links that have 2 or 3 times the capacity of 1-lane links. This is a theoretical limitation of the underlying model.

I plan to implement multi-lane with FIFO (no overtaking) in the future.

Workarounds for the current model:

  • Create multiple links between same node pair; each link corresponds to each lane between the nodes. This is a reasonable solution. However, the analysis becomes tedious.
  • Reduce capacity_out parameter of Link. In this way, we can place a bottleneck to the end of a link, so that capacities of links can vary significantly. However, it only reduce the capacity. Also, the jam propagation speed becomes too fast or slow.

I would really love to have this included! If you want any help or discuss something please let me know.

This will take some time as it requires changes to the fundamental simulation logic.

In the meantime, you can apply this workaround:

Create multiple links between same node pair; each link corresponds to each lane between the nodes. This is a reasonable solution. However, the analysis becomes tedious.

Wouldn't the jam density also be affected on the number of lanes on a link?

Edited to add: I see it now in the code - the jam density is used to calculate the capacity.

Correct.

In the multilane update, I will implement a consistent model parameter definition.

Simulation logic is implemented.

Visualization needs to be updated.