Model Builder - Convert an input XY to a 'point location along a line'

[chrisflory]

Hello all

I have a problem that I believe can be solved with model builder, however I have limited experience using model builder and need some help putting it together.

Problem:
My business is in highways maintenance. Everything we do is located by using 'Sections' and 'Chainage'.
A section is simply a defined length of road which has a unique reference and the chainage is the distance in mtrs along the section.
I have a polyline shp for my roads. Sections have a defined direction and the lines are digitised accordingly so that the start and end are always the right way around.

When any new road surface is laid, we need to know the start and end points of the new road surface in 'section & chainage' format.
It is difficult to record measurements in this way on site as sometimes the beginning of a 'section' will not be accessible and so a measuring wheel can not be used, but we will log GPS locations on site.

Solution:
My idea is to build a model that allows a user to input a GPS location (preferably in 12 figure OSGB e.g. NZ 12345 12345) and for the model to output the 'section' and 'chainage' of that point (or closest possible).

Method:
I think the 'core' tool in the model is going to be 'locate features along routes'. I have used this tool before with existing data in tables.
What I'm stuck with is providing an input because there is no 'feature' as such.

So perhaps I need the first step in the model to create the feature (a point shp)? Is there a tool that creates a point shp by entering coordinates? I thought about 'Make XY Event layer' but does that need a table as an input?

This is where I am up to. I think I know what I want; I just don't have the experience to throw a model together knowing which tools to use. Any help appreciated!!!!!!!

Thanks

Chris

[RichardFairhurst]

Hello all

I have a problem that I believe can be solved with model builder, however I have limited experience using model builder and need some help putting it together.

Problem:
My business is in highways maintenance. Everything we do is located by using 'Sections' and 'Chainage'.
A section is simply a defined length of road which has a unique reference and the chainage is the distance in mtrs along the section.
I have a polyline shp for my roads. Sections have a defined direction and the lines are digitised accordingly so that the start and end are always the right way around.

When any new road surface is laid, we need to know the start and end points of the new road surface in 'section & chainage' format.
It is difficult to record measurements in this way on site as sometimes the beginning of a 'section' will not be accessible and so a measuring wheel can not be used, but we will log GPS locations on site.

Solution:
My idea is to build a model that allows a user to input a GPS location (preferably in 12 figure OSGB e.g. NZ 12345 12345) and for the model to output the 'section' and 'chainage' of that point (or closest possible).

Method:
I think the 'core' tool in the model is going to be 'locate features along routes'. I have used this tool before with existing data in tables.
What I'm stuck with is providing an input because there is no 'feature' as such.

So perhaps I need the first step in the model to create the feature (a point shp)? Is there a tool that creates a point shp by entering coordinates? I thought about 'Make XY Event layer' but does that need a table as an input?

This is where I am up to. I think I know what I want; I just don't have the experience to throw a model together knowing which tools to use. Any help appreciated!!!!!!!

Thanks

Chris

You do need a table as input to Make XY Event Layer, and that is the tool to use.  You are going to have to take the data entered by the user and create a table or feature class at some point, but you can create an in memory table and/or feature class to generate the point event table and locate features along route table if you do not intend to store these values.

1. Basic starting point is to copy a table in memory by borrowing a schema already built to store the Lat Long of the user.  http://help.arcgis.com/en/arcgisdesktop/10.0/help/index.html#/Using_in_memory_workspace/002w0000005s...  To make it simple the copied table should have a single record in it with blank data.
2. Use Field Calculator to fill in the Lat Long fields from user input into the in memory table.
3. Generate the XY point event table (set your environment to the same coordinate system as your routes).
4. Process locate feature along route to an appropriate output (in memory, temporary or permanent table).
5. Do whatever other process you need to do to translate the Route ID and measure to your section and chainage (if the routes are not already built to output this information).
6. Append the final output to a QC database.