My plan is to use routing analysis to create idea running routes. The idea for this came to me when on an easy run. I wanted to pick a flat route which would have a minimal impact on my legs and hopefully speed up the recovery process. It was then I thought it would be cool if google maps and/or GPS navigation systems could account for elevation in its calculations.
In theory I am trying to make it possible for people to enter in the desired distance they want to run, the amount of elevation they want to traverse (probably based off of categories: minimal, intermediate, and high elevation change.....based off the relative elevation of the Eau Claire area), and possibly the general area they want to run around. This could be difficult because routing software calculates from point A to B, and often times when going for a run your start/stop points are the same. So it will be necessary to create predetermined stop points along the way. I will create these manually based off the library of routes created by myself and the cross country team at UW-Eau Claire throughout my 5-years of experience.
Methods:
First I had to find a road network which would perform the necessary routing function I needed. Luckily there was an ESRI streets network on one of the UW-Eau Claire local drives. Next elevation data needed to be attained. Using the USDA Geospatial Data Gateway (http://datagateway.nrcs.usda.gov/), elevation data in the form of TIFFs were downloaded for Eau Claire and Dunn county. Because the area of interest (AOI) was only of the Eau Claire area and the immediate surrounding roads, some the maps were excluded for increased processing speeds. Figure 1. shows the 12 maps before the mosaic process.
| Figure 1. 12 TIFF files before the Mosaic Process |
After the maps are created I will choose one and convert it to vector format. I tried doing this earlier in the week and was prevented by an error, basically only integer rasters can be converted to vectors. After some digging, I realized the my raster was of the pixel type "floating raster." To change the raster to an integer format, I had to use the raster calculator. I found a formula online, but since I didn't need decimal places I simplified the equation to: "int(grid_name)" to get truncated integers (aka no decimal places). Once I was more aware of the tool I found more credible information in the ArcGIS Desktop Help (http://webhelp.esri.com/arcgisdesktop/9.1/index.cfm?TopicName=Int). Since the raster was now converted to the integer type, it now had an attribute table with 182 values. This was a relief because I knew my raster had an elevation change of 182 meters. Now that the raster was of the pixel type "integer" and had an accompanying attribute table I was able to classify the values and convert it to a vector. Figure 2. shows the Eau Claire area and its elevation model classified into 6 categories.
| Figure 2. Elevation Classified into 6 categories...from lowest elevation to highest: cyan < green < yellow < red < grey < white. |
Results:
Problems/Obstacles:
Couldn't find a road network
Downloading elevation maps from USDA Geospatial Data Gateway taking a long time/kept being "interrupted"
Mosaic not looking right (had to change the bit depth from default 8 to 32 bit....this was the bit depth of the rasters I imported)
Working on converting a raster to vector format (raster calculator, then classify the values, then?)
Working on how to create a raster showing degrees of slope (Slope (3D Analyst))
Don't know how to find an pre-existing application I can convert for my application (haven't got that far yet...)
I can see how the routing app will avoid the high elevation areas when trying to create an easy route, but if the end-user were trying to create a more difficult route and run over higher grades of elevation/slope I'm not sure how the application will function....will it keep running up and down the same hill...will the application have to enter in predefined points (stops) to make the application work, which then in turn defeats the purpose of having the application create routes for you.
Conclusion:
Sources:
Talks about the various grades of slope and what they can be used for.
http://www.savesfbay.org/sites/default/files/Topography.pdf