Field Notes Two

Comparing Different UAS Platforms

Introduction

Last week our AT 319 class dedicated a gathering data on the Purdue Wildlife Area.  For this mission, our class was divided into groups of two to form different crews.  Each crew was given a platform to use with a unique sensor.  With multiple datasets being collected, our goal was to compare and contrast between the different sensors.  

Study Area

Our study area was relatively similar to our last mission.  We are again operating over the Purdue Wildlife Area located Northwest of Purdue airport.  The missions took place on 05/22/19.  The weather at the time was partly cloudy with a wind of 10 knots from the North.  The outside temperature was 72 degrees.

Methods

Prior to the flights, we laid out five Propeller aeropoint GPS markers clockwise around our mission area.  The fifth marker was positioned in the center for optimal coverage.  Laying out these markers are important for ensuring higher quality end results for the field images.  The image to the right is the Propeller GPS marker. Below is a list of sensors we used in order to gather this information.  There are also links attached with much more information regarding the sensors.

Hasselblad: 1" CMOS, FOV 77degrees, 20 Mega Pixels 

https://www.dji.com/mavic-2/info

M600 Olympus : 16 Mega pix, 84 FOV 

https://asia.olympus-imaging.com/product/dslr/mlens/12_20/spec.html

M600 Stock: 16 Mega pix, 72 FOV 

https://www.dji.com/zenmuse-x5/info#specs

H520 E-90: FOV 90 degrees +- 3 degrees, 20 Mega https://www.yuneec.com/en_GB/accessories/cameras/e90/specs.html

My flight crew consisted of myself and Austin Sullins.  I was the designated pilot for the Mavic 2 Pro mission and Austin was the visual observer.  There were no problems during the mission.  My only complaint was my landing being subpar because I landed slightly off to the side of the landing pad.

Discussion

The maps and data presented below were made possible by Pix4d and ArcMap.

Above is the different orthomosaics created by the four different sensors.  There were 3 platforms total and the M600 was used twice.  The two different M600 sensors were the olympus and stock sensor.  You are able to see that the sensors with the wider field of view created larger mosaics than the others seen.

The map seen above compares the different DSMs taken by the 4 sensors.  Inset A shows how the different sensors were able to capture the trees.  The higher quality images appear to have fewer smooth flat surfaces were the trees should be.  It is seen in the Hasselblad sensor that the trees are more defined from above while the others sensors have trouble.  This could be attributed to the smaller pixel amount in the other sensors and the higher field of view.  The higher field of view tends to try and stretch the pixels in order to complete the images

The only platform to feature the pond to the West was the E-90 sensor on the H520.  This was either due to the the wider field of view or the fact that the mission was made with farther boundaries to the West.

It is interesting to note the differences in image quality.  Out of all the platforms, the Mavic 2 Pro had the most clear images of the cars.  The other sensors created somewhat blurry or smudged images while the Mavic had the most crisp clear image.

Conclusion

The differences seen are excellent examples for when and where different sensors can be favorable.  If a mission requires a more crisp image then the Mavic 2 Pro could be the desired platform to use.  Although, if the mission requires a larger area to be surveyed than a wider field of view would be the recommended sensor to use.  This could mean that the M600 Olympus or the H520 E-90 sensor would be ideal.  The key takeaway from this lab is that choosing your sensor is integral for good data collection.

S.O.P. and Checklist for Mavic 2 Pro

The following post is what my crew and I perform when planning and getting ready to execute a mission.  We first and foremost need to identify what platform that we are going to be flying.  You can see that for this S.O.P. and checklist are made for our Mavic 2 Pro mission that can be seen in a later post.  It is important to ensure that you use the correct settings that pertain to the mission you are attempting to fly.

Platform: Mavic Pro 2 with Hasselblad Sensor (24mp) data collecting

Lense: 28 mm Lense

Settings: 4K FULL FOV,  Video Coding H.265 for 10 bit color, ISO @ 100, faster shutter speed, Adjust White Balance, Nader,

S.O.P:

• Identify the mission at hand and set parameters.
• Check weather and environmental factors
• Identify pilot and VO (check currency)
• Double checking all equipment
• Identify takeoff and landing area along with emergency landing area.
• Identify

Checklist:

Before leaving for the field:

• Confirm location and purpose of the mission.
• Check batteries for charge.
• Check that all needed items are in the case.
• Check weather (wind, temp, precip, etc.)
• Load up the equipment.

Arriving at the field: (V.O)

• Looking over the mission area for any obstacles.
• Mark the highpoints for trees, powerlines, ect.
• Lay out GCP’s and write down the location and the order you put them out in.
• Lay out the landing pad (if it is needed).

Arriving at the field: (PIC)

• Look around the mission area for any obstacles.
• Make sure the mission plan on measure and the DJI app is correct.
• Find best/preferred takeoff and landing area.
• Set up the props on the drone.
• Set up the transmitter and app on phone or tablet.
• Set up all camera settings.
• Double check props and transmitter.
• Install battery and make sure it is seated properly.
• Place Mavic at the takeoff location.

Field Notes One

Mission 1 Report

Introduction:

Most people do not realize how different phone GPS is compared with a survey GPS.  Our mission purpose was to introduce our class to the elements of setting up a survey environment.  We set up different GCPs throughout the field using single frequency GPS station and Propeller GCPs.

Study Area:

We conducted our survey mission at the Purdue Wildlife Area.  The mission setup began at 11:10 a.m.  The flight occurred at 12:30 p.m.  The weather conditions were wind SSE at 3 mph with clear skies at 400 ft. and with a temperature of 60° F.

Methods:

First we had to establish the boundaries for the mission we wanted to perform. Then we attempted to evenly spread out yellow Propeller GCPs around the field.

These markers seen to the left have an internal GPS to help make processing of data more accurate.

We also spread out traditional single solution tie points throughout the field. 

We attempted to use them but were unable to setup the single frequency traditional tie points because the GPS on the Reach Unit Station (green piece to the left) could not connect to the cellular network.

We used the Mavic 2 Pro set for 400 feet to perform the mission.  The camera was angled at -90° to capture the mission images.  We aborted the first flight early on and then completed the entire second flight.

Discussion

Above in the Purdue Wildlife Orthomap you can see the different details that were important to note for the mission.  In Inset A, it is showing the difference in accuracy between the phone GPS and a surveyor GPS.  The accuracy of the surveyor GPS is within millimeters.  Soon phone GPS' will have close to the same quality as a surveyor GPS.

Inset B displays how high quality the orthomosaic is.  In that picture, I am seen in the purple shirt.  We were originally spread throughout the field to test our teaching assistant's program called Loc8. This program is used for search and rescue using a previous image taken of the missing person that the program references to match different colors.

The image seen above represents the 3D model of the orthomosaic.  Below is an image showing the dsm version of the mosaic.

Conclusion

One of the main takeaways from this mission is that surveyor GPS' are incredibly accurate compared to the average cellphone GPS.  Our class also successfully learned how to operate programs such as ArcCatalog, ArcMap, and ArcScene.  These programs gave us the results I presented.

Welcome to my UAS Blog

Critique

Dylan McQueen, Fall 18, AT 409

In his blog he does a great job of organizing his posts so older one are easier to access.  One area that needs work is his tab labeled Figures. In this tab he does not have any information under it which could look bad.  His design and background are very aesthetically pleasing.

Thomas Gonya, Fall 18, AT 409

Thomas went an interesting route with his blog design.  He used a format of completely black and white.  This had an effect that felt more organized.  It was odd that in his posts that the text went completely to the edge which made it odd to read.  It was a good idea to put a small About Me section on the side bar for the reader.

Evan Hockridge, Fall 18, AT 409

Evan went with a similar design of black and white that Thomas used.  The way Evan used it however was better since he did not use white backgrounds behind the text which could distract the reader.  One major thing that Evan can work on is his handwriting.  His handwriting was barely legible.  He did a great job though of making easy access to past posts by using a sidebar called Blog Archive.

Brian Duffy, Spring 16, Geog 390

Brian does a great job of explaining his pictures and the process for his labs.  He gives relevant information when it is needed and does not overexplain things.  One area that needs work is his own personal information.  When I open his blog I expect to be able to find his information relatively quickly but on his home page his name is no where to be seen.  I did like the design he used because it was not overly distracting and got the job done.

Andrew Jeffers, Spring 16, Geog 390

Andrew's blog design is very simple and pleasant to the eye.  He does a great job displaying his pictures by placing the text to the sides of the images.  Andrew ran into the same issue as Brian though.  His blog also does not show his name anywhere on the homepage.  He does a great job explaining his findings with a thorough analysis.

My Background

I am currently going into my Senior year at Purdue majoring in Unmanned Aerial Systems.  My background with Unmanned Aerial Systems before attending Purdue University was very minimal.  I have flown drones in high school on a number of occasions and thought they were very interesting.  My interest in unmanned systems started when I was a freshmen that was undecided with what major I was going to explore.  I knew though that I wished to explore a field that was related to aviation.  After discovering the unmanned program at Purdue, I knew I was hooked.  

My background with Unmanned Aerial Systems mainly consists of what I have learned during my studies at Purdue.  This would include the safety and regulatory issues relating to unmanned systems. I have had previous job experience teaching younger children how to properly fly smaller drones and how to work with a team to complete drone related tasks.  This was interesting to see how a younger generation was genuinely intrigued by what they could accomplish when properly planning out missions for their drone.

The future with Unmanned Aerial Systems is constantly evolving.  Large amounts of drone traffic will soon be seen throughout the world.  I hope to start a career that is related to more government work.  What I mean by this is more towards the military side of things that would also include outer space work.