Exercise 4 - Unmanned Aerial Systems (UAS) Mission Planning

Introduction

Unmanned Aerial Systems or UAS is a very important tool in the geospatial sciences. It allows us perform field analysis that couldn't be possible on foot. We can collect aerial imagery and analyze spatial patterns from the air quickly and cheaply. In this exercise we were required to log a couple of hours in the flight simulator program RealFlight and try out different types of UAS aircraft. After we have become familiar with the different kinds of UAS aircraft we then will look at two scenarios where UAS would be useful and decide which type of aircraft would be best suited for each specified scenarios.

Flight Simulator

We needed powerful computers to use the RealFlight 7.5 UAS flight simulator software due to the intense processing power needed to render the graphics. We were to chose two fixed-winged aircraft and two multi-rotor aircraft. I chose the Slinger and F-86 Sabre for the fixed-winged aircraft and the Quad-copter and Explorer 580 for the multi-rotor aircraft I was to try out. I picked different locations for the flight sessions for each different aircraft. I was pretty good at this simulator due heavy practice in my youth through Xbox video games. Below I go through each aircraft flight and what I think they are most useful for.

RealFlight 7.5 software package with controller

Fixed-Wing

Slinger

The Slinger was the first fixed-winged aircraft I tried out. It is battery-powered and propelled by a motor propeller in the rear. It was fairly easy to fly and fun to fly around obstacles and was very fast. However, when flying it from a ground viewpoint it was hard to keep in the air when it got far away. This was very fun to fly and entertaining to try and fly it through buildings and other openings.

Slinger aircraft from RealFlight 7.5

	Flight 1	Flight 2	Flight 3
Time	8 minutes	12 minutes	7 minutes
View	From ground	Third person behind aircraft	First person
Wind	15 mph	5 mph	0 mph
Airfield	Junkyard	Junkyard	Junkyard
Reason for crash	Lost view of aircraft and hit the ground	Ran out of battery	Hit bird (kind of on purpose)

F-86 Sabre (Ducted Fan)

This aircraft was a small replica of a real-life aircraft and handled similarly to the Slinger except with more maneuverability and more speed. I tried some trials where I flew through rings and its maneuverability made that pretty easy. The high speeds did make it harder to control but if I kept it higher it wasn't an issue.

F-86 Sabre aircraft from RealFlight 7.5

	Flight 1	Flight 2	Flight 3	Flight 4
Time	5 minutes	7 minutes	8 minutes	6 minutes
View	First person	First person	From ground	From gound
Wind	5 mph	5 mph	5 mph	20 mph
Airfield	Buena Vista	Buena Vista	Buena Vista	Buena Vista
Reason for crash	Hit ground	Hit tree	Hit log cabin trying to go through it	Hit ground

The fixed-wing UAS aircraft had some strengths and some weaknesses. Their strengths are that they can cover large distances quickly, they can fly very high and they are very easy to fly in first person. Their weaknesses are that they aren't maneuverable enough to go through small spaces, they crash easily when out of view or near ground and they aren't easy to fly from the ground. They would be best for collecting data over large distances and collecting data that could be collected high above.

Multi-rotor

Quad-copter

The multi-rotor aircraft were much more difficult to fly than the fixed-winged, but they were also harder to crash. They also were way more maneuverable and stable than the fixed-wing aircraft because you were able to hover and move slowly. However, falling hard will break the rotors and it won't be able to take off again. It is a very fragile aircraft but very stable. I was able to easily maneuver around the castle building and landing was a breeze.

Quad-copter aircraft from RealFlight 7.5

	Flight 1	Flight 2	Flight 3	Flight 4
Time	6 minutes	8 minutes	7 minutes	7 minutes
View	From ground	From ground	First person	From ground
Wind	25 mph	0 mph	0 mph	10 mph
Airfield	Castle	Castle	Castle	Castle
Reason for crash	Flipped over and broke	Hit the ground in the courtyard of the castle and broke most of the rotors	Hit eagle statue	Hit lamp post

Explorer 580

I didn't notice much different between the quad-copter and this one, it was just a different model of the same design. I did notice that flying from the ground was hard to control because it was hard to figure how the aircraft was moving in relation to my perspective. As the aircraft turned it was hard to tell which was the front and changing direction proved difficult in that view. In first person however it was very natural and understandable.

Explorer 580 aircraft from RealFlight 7.5

	Flight 1	Flight 2	Flight 3
Time	5 minutes	18 minutes	6 minutes
View	First person	Third person	From ground
Wind	0 mph	0 mph	15 mph
Airfield	Sierra Nevada Cliff	Sierra Nevada Cliff	Sierra Nevada Cliff
Reason for crash	Ran into a window that wasn't open	Hit tree	Ran into ledge I was standing on overlooking valley

The multi-rotor UAS aircraft had some strengths and some weaknesses as well. The strengths are that they are very maneuverable allowing for flying into buildings, they have longer battery life than fixed-wing, they can move slowly allowing for low flights and they are easy to fly in first person view. The weaknesses are that they can't cover large distances quickly, they can go super high and they are harder to fly from the ground until they are mastered. They would be most useful in data collection that required slow, low fly aircraft. They are most

Scenarios

We were provided a variety of scenarios to chose from that had dilemmas that could be cured by using UAS. Using the information we found in the flight simulator we were to figure out which type of UAS would best serve each scenario.

Scenario 1 - Power Lines

"A power line company spends lots of money on a helicopter company monitoring and fixing problems on their line. One of the biggest costs is the helicopter having to fly up to these things just to see if there is a problem with the tower. Another issue is the cost of just figuring how to get to the things from the closest airport."

In this situation there is a need to not only get a high view but also a stable view so that a diagnostic can be performed on the power line tower. For this situation I would recommend using a GoPro on a multi-rotor UAS aircraft. This would provide the operator to cheaply examine the tower without having to fly an expensive helicopter from the airport. The GoPro would allow them to see everything at the top of the tower which would provide easy analysis of the tower. They would be able to just bring the quad-copter with them and fly it up to any tower they needed to see if further work was needed on any given tower. No matter how many times they would need to analysis a tower or how many towers needed to be looked at, the savings would be immense.

Scenario 2 - Pineapple Plantation

"A pineapple plantation has about 8000 acres, and they want you to give them an idea of where they have vegetation that is not healthy, as well as help them out with when might be a good time to harvest."

This situation covers a large area and needs a moderate level of detail in the data collection. I would recommend a fixed-winged UAS aircraft with a infrared camera under the payload for this situation. The fixed-wing would provide the user with the ability to cover the large plantation. The height of the fixed-wing and the speed at which it would fly would determine the amount of detail that would be achieved. The infrared camera would be used to collection lidar data that could then be processed using normalized difference vegetation index or NDVI analysis which would let the farmer know which parts of their plantation was healthy and which were not. This process could be repeated as frequently as the farmer wanted providing a extremely cheap and up-to-date solution.

Conclusion

Both types of UAS provided different needs in data collection and it is very important to know which to use in different situations. Fixed-winged aircraft are best for data collection that require large distances to be covered and don't require close detail. Multi-rotor aircraft are best for data collection that require slow moving and close, detailed analysis. Some projects could even use both so that you can achieve detail in places while covering large distances.

It is most important to plan ahead and know what kind of data you're collecting (either a need for detail or large area) in order to know which type to use. If you plan ahead, UAS can solve any spatial data collection need with ease.

Sources
Scenarios provided by Dr. Joe Hupy.
RealFlight 7.5 Simulator

Photos:
RealFlight w/ controller: Link
Slinger: Link
Quad-copter: Link
F-86 Sabre (Ducted Fan): Link
Explorer 580: Link