Geospatial Field Methods: Activity #3: Unmanned Aerial System Mission Planning

Introduction

Mission planning is of the utmost importance when preparing for a project, especially when Unmanned Arial Systems are involved. Unmanned Aerial Systems (UAS) can cost thousands of dollars and because many of the parts that make up a UAS are specialized, it can be difficult to maintain or replace. When planning for an outing that will use UAS technology it is important to choose the right type of Unmanned Ariel Vehicle (UAV), proper sensors, and to choose the right time of day and year to execute the mission. UAS along with remote sensing technology can be useful for many applications, such as: terrain modelling, topographic surveys, inspection work, monitoring deforestation and vegetation health, mapping structural attributes like biomass and basal area, and the list goes on. The field of UAS has been and continues to grow quickly and the need for people that understand how to properly plan and execute UAS missions has become steadily more prevalent.

Students were given five different scenarios in which UAS could possibly be used but currently was not. For each scenario, the students were to decide which type of UAS to use, which kind of sensors to use, and to think of any limiting factors that could hinder the mission from any point during its process. Given only the scenarios and a couple websites to get started, students could use any means necessary to find solutions to each scenario that involves the use of UAS.

Figures

Figure 1: The APM Copter offered by 3D Robotics. An example of a rotary craft. This is the basic ready-to-fly version with a base cost of $749.99 with configuration options available for added cost. Upgraded models of this UAV are available ranging in base price up to $1,350. Just the copter frame can be purchased along with all the indivdual electronic parts to construct your own UAV. 3D Robotics (use side panel to explore parts options)

Figure 2: The APM Plane offered by 3D Robotics. An example of a fixed wing craft. This is the basic ready-to-fly version with a base cost of $569.99. Configuration options are availabe for added cost. 3D Robotics

Figure 3: The Canon S-95. Captures visual and near-infrared (NIR) light.

Specifications

Resolution	Field of View	Weight	Spectral Bands
3264 x 2448 pixels	50 x 39 degrees	250 g (0.55 lbs)	RGB, NIR

Figure 4: The ICI 7640 Thermal Camera. Captures thermal long wave infrared (LWIR) light.

Specifications

Resolution	Field of View	Weight	Spectral Bands
640x480 pixels	48x37 degrees	127.6 grams (4.5 oz)	7-14 microns

Figure 5: SOC710-GX Hyperspectal Imager

SOC710-GX System Specifications

Spectral Coverage: 400-1000nm

Spectral Resolution: 4.2nm

Bands: 120

Pixels per line: 640

Speed: 90 lines/second

Focal Length: Configurable

Lens Type: C-Mount

Weight: 1.25 Kg*

Dimensions (DL): 10.3cm x 20.0cm*

Power: 12-VDC / 10 Watts

Figure 6: Fixed Wing vs Rotary

Fixed Wing

Flight Time	Longer
Speed	Fast
Structure	Simple
Best Use	Aerial Mapping, Terrain Modelling larger areas (mine sites, stockpiles), Topographic surveys
Flight ability	One-Way, circle pattern
Limitations	Need takeoff/runway, can’t carry all types of payloads, no hover capability

Rotary

Flight Time	Shorter
Speed	Slow
Structure	Complex
Best Use	Inspection work, hard to reach areas (pipelines, bridges, power lines, rail tracks)
Flight Ability	Every direction horizontally and vertically, hover
Limitations	Short flight time and complex maintenance

Scenarios

1. A military testing range is having problems engaging in conducting its training exercises due to the presence of desert tortoises. They currently spend millions of dollars doing ground based surveys to find their burrows. They want to know if you, as the geographer can find a better solution with UAS.

The best type of UAV to use for this case is a fixed wing craft. With a fixed wing craft, large areas of desert can be covered and analyzed. The desert landscape is perfect for construction of runways which are needed for take-off and landing of fixed wing UAVs (figure 6). The desert tortoise lives in burrows which need to be kept at temperatures lower than 85 degrees Fahrenheit or the tortoise will suffer brain damage. The resulting tempertures of these burrows is lower than the surface temperature in the deserts of the southwestern United States. The ICI 7640 Thermal camera can be utilized to see this temperatures differences between the desert tortoise’s burrows and the surrounding surface temperature. By viewing this temperate data, the burrows of the desert tortoise can be found and avoided.

2. 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 case, a rotary craft would be ideal. Complications in transporting crafts from the airport and the great cost of flying helicopters would no longer be a problem. The small size of a rotary UAV like the APM copter in Figure 1 is perfect for easy transport. The maneuverability and hover capability of a rotary UAV (figure 6) will make inspections of the power cables quick and easy. By fixing a Canon S-95 (figure 3) to the craft, quality pictures in the visible spectrum can be captured and analyzed for problems in the tower. The combined cost of a rotary UAV and Canon S-95 (figure 3) is far lower than even just one flight in a helicopter and the setup will provide quick quality results.

3. 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.

With such a large area to cover, a fixed wing craft would suit this scenario best. The longer flight time and faster speed of a fixed wing craft compared to a rotary craft (figure 6) will allow for a more extensive area to be covered. By utilizing NIR and hyperspectral images, photosynthetic processes can be monitored which include both vegetation health and growing-season length. The Canon S-95 (figure 3) and/or (depending on payload capabilities) the SOC710-GX Hyperspectal Imager (figure 5) can be used to capture the images needed for analysis.

4. An oil pipeline running through the Niger River delta is showing some signs of leaking. This is impacting both agriculture and loss of revenue to the company.

Because the oil pipeline in the Niger River delta is hard to get to by person, a rotary craft would be best to perform the needed inspection. Great maneuverability is needed to follow the pipeline and detect leaks which a rotary craft would be able to handle (figure 6). Using the Canon S-95 (figure 3) or the SOC710-GX Hyperspectal Imager (figure 5), would enable oil sheens and stressed vegetation health to be seen and monitored. Cloud penetration is lacking for these kind of sensors, so a clear cloudless day is needed.

5. A mining company wants to get a better idea of the volume they remove each week. They don’t have the money for LiDAR, but want to engage in 3D analysis.

Depending on the size of the mine, either a fixed wing or a rotary craft could be used. By using both the Canon S-95 (figure 3) and the ICI 7640 Thermal Camera (figure 5), three sets of data (RGB, NIR, and Thermal) can be combined and utilized to create an accurate 3D model of the mine each week. A cloudless day is needed for quality images.

Sources

http://www.infraredcamerasinc.com/infrared-camera-7640.html

http://aggieair.usu.edu/aircraft

http://surfaceoptics.com/products/hyperspectral-imaging/710-gx/

http://diydrones.com/

http://planner2.ardupilot.com/

http://planner.ardupilot.com/

http://www.usa.canon.com/cusa/support/consumer/digital_cameras/powershot_s_series/powershot_s95
http://www.mdpi.com/2072-4292/3/9/1847

http://www.ciesin.org/TG/RS/sarsens.html

http://150.197.2.88:8080/MultiData/A0156/265/12.pdf

http://www.whrc.org/education/rwanda/pdf/Walker_SAR_Veg_Mapping.pdf

http://www.militaryaerospace.com/articles/print/volume-24/issue-10/technology-focus/electro-optical-sensor-payloads-for-small-uavs.html