Managing Nodes

Case A

The new geometry uses some or all of the turns in the base geometry.

After selecting the Nonexistent Here and Existent Only Here objects, you’ll see part of the original node.

Double-click on the node to access the editor and then create the new turns between base sections and new sections, and also between new sections.

When using the Connection tool, do not create a turn between two new sections first because it will create a different node. You must involve a base section when creating the first turn.

Case B

The new geometry doesn’t use any turns from the base geometry.

After selecting the Nonexistent Here and Existent Only Here objects, you won’t see the original node; however, all or some base sections are involved in the new geometry.

Even though the node is not displayed, it still exists, so in order to create the rest of turns you must use either the Connection tool or the Node tool.

If you use the Connection tool, do not create a turn between two new sections first because it will create a different node. You must involve a base section when creating the first turn.

If you use the Node tool, make sure that you include a base section in the selection.

Using Existing Nodes

Duplicating objects

In some cases, streets and roads will undergo changes such as number of lanes, direction or lane availability for turns. While these changes wmay not necessarily entail a physical change in the infrastructure, in Aimsun you’ll have to duplicate the sections to code the new Geometry Configuration.

Here are a couple of examples

1. The new section has a different number of lanes
   
   
2. The new section is in the opposite direction
   
   
   
3. There is a different connection between lanes for the same movement (turn). You’ll have to create a new turn but since there can only be one turn between the same two sections, you’ll have to use new sections to create it.