footpaths and pedestrian crossings

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09-27-2011 10:52 PM
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New Contributor
I am creating the network dataset for pedestrians. I have these layers:
1) footpaths which break when they intersect driveways or pedestrian crossings
2) pedestrian crossings (e.g. signalised crossings, zebra crossings)
3) permeability polygon layer (class 1-4 e.g. with fences (cannot pass through), with void decks, town centres promenades (pedestrians can walk everywhere)

A) the permeability layer did not auto appear in the new network dataset though it has been imported to file Geodatabase feature dataset - is there any criteria for the required layers to appera in the new network dataset?

B) In ArcMap, when i test the find shortest route.  "No route found" is displayed whenever it crosses the pedestrian crossings or when there is a gap in between the footpath layer.
How do i join the gap or how do i link it with the driveway layer to make the network continuous?
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Esri Regular Contributor

A) the permeability layer did not auto appear in the new network dataset though it has been imported to file Geodatabase feature dataset - is there any criteria for the required layers to appera in the new network dataset?


A polygon layer cannot be made part of a network dataset as it is only made from lines and points (if needed).
However at analysis time, you can bring in such data as scaled cost polygon restrictions. For example, create a Route Analysis layer and then in the NAWindow, right-click on the polygon barriers and choose Load Locations to load these polygons in (as Scaled Cost and not Restrictions) and then choose an appropriate value to scale the cost of going through that area. Note that these polygons only "scale" the edges or junctions that are inside them. You cannot travel where edges do not exist.

B) In ArcMap, when i test the find shortest route. "No route found" is displayed whenever it crosses the pedestrian crossings or when there is a gap in between the footpath layer.
How do i join the gap or how do i link it with the driveway layer to make the network continuous?


You will have to edit your street data to add the missing edges that connect the gaps. Make sure snapping is on so that correct connectivity is built.

Jay Sandhu
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Thank you for your reply. I have further queries.
1) For footpath and pedestrian crossings: is there any automatic way to join the edges? other than manually shifting the footpath/crossing to snap
2) Under the dataset properties, the element type should be edge for both? Connectivity policy should be end point for both?
I have tried to snap the pedestrian crossing with the footpath for a small stretch and try to find the shortest route. But it still display no route found. could it be other reasons that i have missed?
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Have tested short sections of the routes. There is always no solution found when there is a change in direction e.g. when the footpath splits into different directions. How do i treat this problem?
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Esri Regular Contributor
The end points of lines have to be exactly coincident for a network dataset to find connected edges.

Most likley your data is not connected when you zoom in closer. One way to check connectivity is to use the network identify tool. It is the second icon from right on the NA toolbar. Click on any edge and it will show it's values as well as what it is connected to. Use it in the locations you cannot find a path to see if connectivity is the problem.

You could try to fix connectivity problems automatically with the GP tool Integrate. Make sure to make a copy of your data first as it will modify the existing data and if you choose a wrong tolerance, it may collapse some features. You can read more about it here:
http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Integrate/00170000002s000000/

Once you integrate, rebuild the network dataset.

Jay Sandhu
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