Field Notes 1

Mission 1 Field Notes: 5/14/2019

Intro:

Despite common belief not all GPS systems are created equal. In this lab my team and myself preformed a mission setup that would allow us to collect three separate GPS data points from the exact same locations using photos from each team member’s phone, single solution, and fixed solution GPS signals.

Purdue Wildlife Area

Study Area:

We were at Purdue Wildlife Area,8000 IN-26, West Lafayette, IN 47906. Weather was a perfect 63 degrees Fahrenheit with winds out of the SSE at 3 MPH with no gusts with clear skies at 400 feet 
AGL. We flew the Mavic 2 pro at an altitude of 400 feet AGL and the camera set at 90 degrees down.

Methods:

Propeller GCP’s:

We deployed the plates in a scattered way that was unorganized. We took two bags filled with five plates each. Four team members left with each bag and scattered out throughout the entire field. We didn’t note what plate was turned on first or even where the plates were. This caused us problems later on for the cleanup when we had to walk the field in a line looking for the GCP plates. Even with that small oversight we were still able to collect accurate GPS data using the Measure website and the Propeller software.

Traditional GCP’s

The reach unit couldn’t connect to the cellular server. Which made it so that we had to go and make a static measurement at each of the GCP’s known as Single Solution GPS Coordinates. We made sure not to lay these down right next to the Propeller GCP’s so we could get the most data possible.

Photo Based GPS of the Traditional GCP’s

After we took the static location of the Traditional GCP’s each team member took a photo with their phones so we could find out how far off our phones GPS was from the more accurate GPS devices.

Traditional GCP

Propeller GCP

Conclusion 

Mission
My crew executed a mission that had a few errors in it that ended up being great learning experiences for me and my entire team. We initially planned to fly this mission at 121m (400 feet) over the Purdue Wildlife Area for a test of a software system that is designed to find color codes and circle them on the images to aid in search and rescue.

The mission was then flown at 300 feet and the data was collected and used for more learning experiences with arcmap and other arc software frames. I went and expanded out into more areas that would be beneficial to whomever will be using this data. Below I have the images of the data that I have made.

Map of Purdue Wildlife Area
As you can see in Figure 1 there is such good detail in the images that you can clearly see the GCP's that are less than 2'x2', and also a person (Evan Brueggemann) laying in the grass. You can also see how much error there is between a phone GPS and the actual GCP's that we placed out in the field. In some locations the phone GPS was within a few meters of, and in other locations it was no where near the GCP. This just proves that our GCP's are more accurate and reliable then phone GPS this is why we use them. It also is easier to get the images and data approved by professional surveyors which is a critical part of data being reliable.

Figure 1

3D Flood Diagram

I decided that it would be critical to know the critical flood areas, normal flood area, and obstacle over 50 feet. The reason I chose 50 feet or more is because that is something that is used for all air crafts. Distance for takeoff over a 50 foot obstacle is something that is discussed in every pre-flight for manned aircraft, and is something that will also be helpful to drone pilots and crews.

All areas that are red are obstacles over 50 feet, the dark blue areas are your critical flood areas, and the lighter blue is the area that will flood but is less likely to. The green area is the ground above the flood zones and below 50 feet. Most of the critical flood area is across the road in another field that is not the Purdue Wildlife Area. There is one small section that is prone to heavy flooding, but it is not near any parts of the field where anything is planted so the workers don't have to worry about their crops getting ruined from a normal amount of rain.

Figure 2

Figure 3