Exercise #13: UAS Flights

Introduction

Earlier in the semester the class was able to learn the basics of Unmanned Aerial Systems (UAS) and experiment with operating these devices on a computer simulator. During this exercise we were able to learn and observe what the pre-flight protocols, mission planning, and actual flights consisted of. It is very, very important to be prepared and plan before going into the field to collect data. This exercise included flying two different UAS platforms: the IRIS (Fig 1) and a Matrix (Fig 2).

Figure 1. The IRIS platform flown during the exercise.

Figure 2. The Matrix platform flown during the exercise.

 

Study Area

The study area for this exercise was once again the Priory (Fig 3). The Priory allowed wide-open spaces with a low volume of people or tall objects.

 

The weather consisted of:

        *Temperature: 52 degrees Fahrenheit

        *Cloud Cover: Cloudy, Stratus

        *Wind: 6-8mph S-SE; Gusty   

 

Figure 3. The UWEC Priory. This was the study area for the given exercise.

 

 



Mission Planning

 



One important aspect of flying UAS platforms is to create a Flight Mission. The Flight Mission communicates from the base station (either a computer (Fig. 4) or tablet (Fig. 5)) to the platform. Along with being connected to satellites and GPS, the base station controls the platforms movements if set on autopilot. This autopilot can be overridden at anytime by the Pilot. There are various base stations that can be used and each have their pros and cons. By using a computer, a person has more options and abilities to create more complex missions, but a computer is also very bulky and large. A tablet is light and easily to be carried, but has less options associated with it.

There are two ways in which a mission can be created. Either the manual plotting of points can be made over the given area or the computer can plot the points. By drawing a polygon shape over the AOI, the program will automatically (Fig 4). The specs of the senor or camera will depend on the number of points needed. The point mark areas the unit will turn or change direction.

Figure 4. The base station with the mission polygons drawn over the AOI.

 

 



Figure 5. Example of a tablet used when flying UAS units.

Pre-Flight 

One of the most important parts of flying a UAS platform is preforming a pre-flight checklist (Fig 6; Fig 8). By creating a checklist, like the one below, it ensures both a successful flight and that it is safely done. Safety of yourself and others is extremely important when flying a UAS platform. If something would not be fully connected, the unit could descend and cause injury, but also it could destroy the unit and sensor itself.

Safety is most definitely important, but so is a successful flight. If the sensor is not properly connected or the mission is not properly set up then it cause no data to be collected. This is a waste of time and money. By double checking oneself issues like this can be avoided.

Figure 6. Preforming the pre-flight checklist.

Pre-Flight Checklist (Fig 7)

1. Check Weather Conditions and Record

On Platform
2. Check Electrical Connections
3. Check Frame Connections
4. Check Motor Connections
5. Props Secure?
6. Props not cracked or chipped
7. Battery Secure?
8. Antenna Secure?
9. Sensor Connected?

Power Up Sequence
10. Green Light on Platform? (Indicates connected to Satellites/GPS)
11. Connect to Platform from Base Station
12. Batteries over 95%?
13. Transmitter on? Batteries charged?
14. Record number of available satellites
15. Mission Created?
16. Mission Secure? Area Clear?
17. Mission Sent?
18. Sensors on? At ready?

Take off Sequence
19. Throttle down?
20. Platform on
21. Spectators clear?
22. Kill switch off?
23. Clear for Launch
24. Activate Auto-pilot

Figure 8. Example of the pre-flight checklist on the base computer. It is important to recorded information like this to prevent failure and issues in the future.

 

 

 

Flights

 

Once the Flight Mission and Pre-Fight checklist have been completed, it is time to flight. By continuing with the checklist, the power-up and flight sequences can be followed (Fig 7). One of the most important concepts of flying is COMMUNICATION! The Pilot in Command and Unit Pilot must always be communicating. Once the unit is launched, variables like the number of satellites, if the platform is on coarse, and where is the platform located must always be watched. If something goes wrong, the Pilot in Command can abort the mission and the platform will automatically land itself (autopilot) or it can be manually landed. Just because the unit is on autopilot, it is extremely important to keep your eyes on it at all times incase an issue would occur.

 

Once a mission has been completed, it is important to fill out a Post Mission Log. By doing so, this is a place that issues and problems can be recorded to used for reference in the future. Things that would have gone into our log would have been the battery issues that included dead batteries, but also not to interchange batteries between controllers.

 

Pictures of the flights:

 

 

 

Data

 

Once the flight has been successfully flown, the data can be downloaded and processed through the software. With advancements in software, data can now be precessed right in the field. This has major advantages since a person can make sure the collection process was a success and all areas were covered. The software can process the image tiles into different photographs like RBG and IR.

 

Examples of the mosacis made in the field from the flight of the Matrix platform:

 

 

Final Remarks

 

This was an extremely educational and awesome experience. UAS units and technology are definitely the frontier of Geospatial Technology. I hope in the future that I will be able to learn more able this technology and utilize it in my research. 

 

Exercise #12: GPS Navigation

Introduction

Last week we were able to learn and utilize traditional navigation skills by navigating to pre-selected and placed points in the Priory. This week we were given the opportunity to build our own coarse for future classes. By creating a project onto a GPS unit (we chose the Trimble Juno Unit) we were then to navigate to points of our choice, mark the trees, and record the points.

Study Area

Once again this week we were at the UWEC Priory (Fig 1). Our study area was divided up into a different area for each given group. This was so the courses would not overlap or be located in one portion of the area. Our group had the far Northeast corner. The weather was Sunny, mid 70 degrees Fahrenheit, and little to no wind.

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Figure 1. The UWEC Priory.

Methods

Once our group was given the selected area for our coarse, we took the paper maps we had created earlier in the semester and used last week and plotted points where we felt necessary. We wanted to make sure the points included distance, terrain, and were easily able to be navigated to within the class period. By having a project created on the Juno Unit (Fig 2), the Priory satellite imagery was available for us to use. This was our means to navigating to the points we selected. Once the points were navigated to, we were to mark the tree with the pink ribbon, label the ribbon with the group number and point number, and take a picture. The pictures of the five (5) points can be seen below (Fig 3-7).

Figure 2. The Trimble Juno 3D GPS unit used for the activity.

 

 

 

Figure 3. Point #2-1 for Coarse #2.

 

 

Figure 4. Point #2-2 for Coarse #2.

 

Figure 5. Point #2-3 for Coarse #2.

 

Figure 6. Point #2-4 for Coarse #2.

  

Figure 7. Point #2-5 for Coarse #2.

 

 

The points that we plotted were then loaded back into ArcMap and mapped (Fig 8). This also allowed us to create a Shapefile to submit so the data could be recorded for future classes. The attribute table gives the location of the points (in UTM) and also notes about the location of the tree.

 

 

Figure 8. Map of Coarse #2. The green dots represent the planned spot for the points, while the red dots are the actual locations of the points.

 

Figure 9. Attribute table of the points for Coarse #2.

 



 

Discussion

 

This exercise was extremely helpful with refreshing the skills we learned earlier in the semester, but also applying those skills to a navigation situation. Although you would think it would be easy to navigate to these points, there are still errors associated with the GPS unit. Looking at the map above, not one of the points match up exactly. This could be due to a low satellite frequency on the GPS or the group just saying we were "close enough" and marked the point. You still also need to account for terrain and obstacles while navigating.  

Exercise #11: Traditional Navigation

Introduction


Earlier in the semester, the class had created maps to be used later for a traditional navigation exercise. This week we completed that exercise. We were given printed versions of the maps we made, coordinates to travel to, and a compass to give bearing from point to point. This is a skill that is most defiantly needed since GPS technology is not always available depending on the area you are in and studying.





Study Area


The study area for this exercise was the University of Wisconsin- Eau Claire (UWEC) Priory (Fig 1). This is a very secluded area that is heavily wooded with trees and small brush. The weather included Sunny skies and mid 60 degree temperatures.

Figure 1. Aerial image of the UWEC Priory. This was the site for the traditional navigation.

Methods


The purpose of this exercise was to take a traditional map (Fig 2) and try to accurately plot given points and navigate from point to point and end back where we started. To do so, we first had to plot the points. The points were given to us in UTM coordinates. How accurate we were definitely depended on the scaling of our maps and grid scale.


Next, we were given our compasses and needed to calculate the azimuths from point to point. The first step is to set the compass on the map (not on or near any metal surfaces) and line it up with the first point and the point of interest (Fig 3). It is important to make sure the arrow of travel is going in the correct direction (pointed towards point of interest). Next, turn the bearing on the compass so that North is accurately pointing North (Fig 4). Reading the degrees at the arrow of travel and this is the azimuth to use while traveling to that point (Fig 5).


Do this for all point to point travels and record since it is much easier to do on a flat surface compared to out in the woods. You can calculate the distances by using the scale bar so that you an rough estimate of how far is needed to travel.


When traveling, keep the red arrow (north arrow) lined up with the red outline and keep traveling towards the arrow.

Figure 2. Map created in previous exercise of the Priory. The map with the UTM grid was used to complete the exercise.

 

 

Figure 3. First step in calculating the azimuth. Line the compass up with the start point and point of interest. It is import to make sure the arrow of travel is in the correct direction.

Figure 4. Second step in calculating azimuth. Turn the compass bearing so that North is accurately pointing North.

Figure 5. Step three of calculating the azimuth. Read the degrees at the arrow of travel.

Figure 6. Set the azimuth and keep "Red in the Shed" (line red arrow up with red outline) and travel to desired point.

 

Discussion


This is a very vital skill to know and use. GPS is not always available and your life could depend on knowing these skills. Our Azimuths were mostly accurate, but could have been more precise if our map had better scaling on the grid. Some points were generalized since the grill scale did not have enough smaller intervals.


Although calculating the distances from the map can be useful, they are not nearly accurate. Depending on the terrain, the distances were longer then planned as we counted our paces. The terrain in the Priory can be very steep in places and includes several valleys. Depending on the objects on the ground, you can not always walk in a straight line and can set you off pace.