Using cost array to act as effect of speed on movement

Discussion created by MikeEber on Sep 9, 2013
Latest reply on Sep 19, 2013 by xander_bakker
I'm new to ArcGIS programming and looking for some assistance here.  We are running ArcGIS 10.1 server, Spacial Analysis for Raster Layers, and the 2500 version of ArcGIS explorer.

We are using a boats' area of responsibility as a limiter for the distance it can respond to issues for 15 minute segments out to 90 minutes.  Today our response vectors are just running the boat flat out at full speed without any external influences.  This may be fine where the AOR is on the ocean, but not good in rivers.  We pass a value which is the distance covered in each segment of time minus the time it takes for the crew to initially respond based on day or nighttime events.

We need to be able to take into account no wake zones, speed limits, and the possibility that a barge is blocking the path and needs to be carefully passed before returning to full speed.

The current server code does generate a raster (I assume this is the full area of response) passing the values for the 6 segments.  Then they create a cost array (and I believe this is where I inject the speed limits, blockages, etc) and then do the final call to get the polygons to draw.

So I wondering how to set up this cost array so that the values act as speed limiters on the process.  So showing below:

Max speed 46 knots
Distance covered in 15 minutes


                |   20 knot limit  |

Final vector (source raster array with speed limit applied in cost raster array) should be


Since the two arrays are added together do I set the cost array to -26 for that area?  The documentation only talks of positive values in the cost array.

Thanks for any assistance anyone can provide.