Modelling controlled intersections with Legion pedestrians

Technical Note #7

December 2014


Aimsun allows 3 kinds of pedestrian-vehicle interaction:

  • At uncontrolled intersections
  • At fixed controlled intersections
  • At actuated controlled intersections

This technical note focuses on how to edit controlled intersections, where the basic infrastructure consists of pedestrian crossings, signal groups and pedestrian routes.

Here we go……

You can position pedestrian crossings either at the beginning or at the end of any section. The image below shows how you can use two consecutive pedestrian crossings to model a regular crossing.

Two consecutive pedestrian crossings

When editing the node containing both pedestrian crossings, you can include them in any of the signal groups. In order to simplify control, both pedestrian crossings belong to the same signal group.

pedestrian crossing Setting a Use Percentage in the matrix

Click to enlarge: Both pedestrian crossings belong to the same signal group

Now create a pedestrian route that passes through the pedestrian crossings and set a Use Percentage in the matrix.

Setting a Use Percentage in the matrix Aimsun traffic modelling software

Click to enlarge: Setting a Use Percentage in the matrix

At this point, there is no difference in how you define a fixed or an actuated controlled intersection.

The next step is to define two different control plans (one fixed, one actuated).

Defining a fixed control plan, Aimsun traffic modelling software

Click to enlarge: Defining a fixed control plan

There’s nothing else to define, so now add the mixed control plan to a master control plan and simulate.

Actuated control plan Aimsun traffic modelling software

Click to enlarge: Actuated control plan

Use actuated control plans to model push-buttons. Pedestrian phases don’t have any detectors defined – before simulation begins, Aimsun automatically creates and defines them.

Aimsun traffic modelling software pedestrian crossing

Click to enlarge: Aimsun automatically creates and defines detectors

This definition ensures that when a pedestrian reaches the pedestrian crossing, the pedestrian phase is called and the pedestrian crosses the street.