Using GIS Resources to Help Plan UAS Missions
Part 1 of a Series of Mission Planning Stories
Picture This
You are part of an engineering consulting company that wants map out newly discovered erosion issues at Rich Creek Virginia. In this scenario, the area of interest is difficult for people to access, and the airplane responsible for aerial imagery has been grounded for routine maintenance. In an effort to mitigate the amount of crew and hazards associated this mission, you employ a fixed wing UAV to help perform the survey.
Questions to Consider
When Planning a commercial UAS mission in areas with mountainous terrain, it is vital that you select the correct platform, the correct sensor, and have a holistic understanding of pertinent FAA regulations outlined in Figure 1.
Figure 1: Pertinent FAA Regulations
Selection of UAS
Depicted in Figure 2 is the completely autonomous selected UAS. In other-words, once it is launched from it's starting point, the UAS crew must be confident that it will not encounter any hazards. GIS can help address hazards before they are discovered on the field.
Figure 2 Catapult Fixed Wing UAS
Airspace Hazards
During the mission planning process one of the first items that need to be identified is the airspace. Highlighted in Red from a sectional chart you see on the right, it is obvious that the proposed operating area is in mountainous terrain, is over a few roads and includes a sparsely populated area.
From a geographical standpoint, it is vital that the team has an a better understanding of the terrain that that the UAV will be flying over let alone other logistical items such as determining where to set up, determining where to launch, determining where to place visual observers, determining where shadows will occur, emergency routes, etc.., These items can be identified using the portal tool from ArcGIS Pro.
Elevation Hazards
Displayed on the right is the mountain range after being clipped, geoprocessed, and classified with colors to delineate various elevation values. When done correctly, you can obtain fairly accurate elevation data which can help you verify what elevation you want your UAV to fly above.
Referring to Figure 3 you want to launch the UAV at a field above Point A but are unsure if about the elevation of Point B.
Figure 3: Uncertain Elevation from Point A to Point B
When the data is reclassified, you not only determine elevation estimates but realize that the UAV will be unable to clear Point B with it's current autonomous settings.
Figure 4 Reclassified Elevation Data
Thanks to GIS, you were able to adjust your mission settings to clear the mountain and can now launch the UAV. (As shown in the video below)
Video: UAV Launch
Looking at the Bigger Picture
While using Arc Pro, you can pan out to gather an aerial view and notice where bodies of water and uneven terrain meet as shown in the image on the right. When overplayed with features from the USA National Hydrology Data-set and the World Terrain Reference, you will be able to make more determinations shown in the image after.
Identifying Further Hazards
The image to the right includes road names, elevation values, and water runoff. From these items, you can identify an access road to unload the UAS, you can identify areas that might cause sensor reluctance such as the stream in the middle of one of the mountains and you can see elevation values of the highest features.
Using the Slope Tool
Depicted by the red lines on the right is a zoomed in analysis of a slope. These lines can be transcribed into graphs showing elevation totals that you can see in the following images. Notice how the elevation height fluctuates int different areas of the mountain.
Scroll Through the Different Profile Graphs
By scrolling through the different profile graphs, you will notice that the mountain has different crevices the higher up you go. knowing these differences will help you determine your flight path for your UAV, your sensor calibration, and where to place your Visual Observers before getting to the field.
Looking Ahead
In the next story, we will use the profile graphs and the Viewshed tool to place visual observers at the optimal locations to ensure that the UAS operation complies with FAA Part 107.33. In the mean time, To learn more about Using GIS to help plan UAS missions, check out my online portfolio at https://alanpecor.blogspot.com/
