As part of our mission to test drone technology and provide mapping services to the ANR community, IGIS recently completed data collection for our largest drone mapping project to date - 3600 acres of the Mojave Desert.

The drone data will be used to create fine resolution vegetation and elevation maps, as part of a desert tortoise research project led by Dr. Brian Todd in the Dept. of Wildlife, Fish, and Conservation Biology at UC Davis. The study seeks to better understand how the threatened desert tortoise navigates in its landscape, which will help biologists and land managers responsible for protecting the desert tortoise make management decisions, such as where to place road fences that don't cut off important resources for this long-lived species. Researchers on this project track the tortoises with GPS and temperature sensors, which they will now be able to overlay on the highly detailed maps of the desert generated from the drone imagery.

How does the desert look to a tortoise?

A Large Study Area

The study area is approximately 3600 acres, which is extremely large for a drone. We mapped the area in two trips in 2016 and 2017, with significant improvements to our mapping methods in between.

In mid-2016, IGIS Academic Coordinator Sean Hogan mapped the first 1200 acres using a 3DR Solo drone flying a consumer grade GoPro camera. GoPro cameras work surprisingly well for making 3D topographic models, thanks to their high resolution, wide field of view, and rapid shutter rate. Hogan programmed the drone to fly a lawnmower pattern with a lot of overlap between images, so every point on the ground is captured in multiple images taken from different angles. The stitching software uses photogrammetric algorithms to recreate the surface geometry, producing a 3D model of the topography.

The Solo+GoPro combo worked well, but the flight time of the Solo, its mediocre GPS receiver, and the lack of an integrated GPS module in the GoPro were limiting factors that required more time for both flying and processing the data.

New Drone Platform for 2017

In May 2017, Hogan returned to the Mojave with IGIS Academic Coordinator Andy Lyons, as well as new equipment and almost a year's worth of additional flight experience. For this campaign we flew our new DJI Matrice 100; a larger drone that can carry two batteries for longer flight times. Hogan also modified the bottom of the Matrice, outfitting it with an additional camera mount, so we were able to fly with a high quality RGB camera as well as the Parrot Sequoia multispectral camera. The combination worked brilliantly, allowing us to capture both high quality RGB images for the 3D surface model, as well as multispectral images for vegetation analysis during each flight. After a day of working out kinks with the cameras and software, we were able to reliably fly eight 100-acre flights per day with minimal downtime between each consecutive mission. Flying at 400 feet, the resolution of the resulting maps will be about 2.25 inches for the RGB orthomosaic and digital elevation model (DEM), and about 4.5 inches for the multispectral products.

Lessons Learned

Some lessons learned for mapping large areas include:

• Mapping large areas with a quadcopter is viable with careful planning
• The Matrice 100 is large enough has enough power to fly 100 acre flights with two cameras on board with two batteries and calm winds
• Heat can dramatically reduce flight time because the air is thinner and equipment less efficient
• Checking your data in the field and having backup plans for weather and equipment glitches are essential
• Having two or more people on the flight crew helps tremendously
• Developing individual mission plans before going to the field reduces time between flights and hence illumination differences between adjacent areas
• The dessert tortoise is a charismatic creature with amazing adaptations, and a great curiosity about the research equipment we were setting up alongside the road:

Day 3: I opened the day with a lovely swim with Elizabeth Havice (in the largest pool in New England? Boston? The Sheraton?) and then embarked on a multi-mile walk around the fair city of Boston. The sun was out and the wind was up, showing the historical buildings and waterfront to great advantage. The 10-year old Institute of Contemporary Art was showing in a constrained space, but it did host an incredibly moving video installation from Steve McQueen (Director of 12 Years a Slave) called “Ashes” about the life and death of a young fisherman in Grenada.

My final AAG attendance involved two plenaries hosted by the Remote Sensing Specialty Group and the GIS Specialty Group, who in their wisdom, decided to host plenaries by two absolute legends in our field – Art Getis and John Jensen – at the same time. #battleofthetitans. #gisvsremotesensing. So, I tried to get what I could from both talks. I started with the Waldo Tobler Lecture given by Art Getis: The Big Data Trap: GIS and Spatial Analysis. Compelling title! His perspective as a spatial statistician on the big data phenomena is a useful one. He talks about how data are growing fast: Every minute – 98K tweets; 700K FB updates; 700K Google searches; 168+M emails sent; 1,820 TB of data created. Big data is growing in spatial work; new analytical tools are being developed, data sets are generated, and repositories are growing and becoming more numerous. But, there is a trap. And here is it. The trap of Big Data:

10 Erroneous assumptions to be wary of:

1. More data are better
2. Correlation = causation
3. Gotta get on the bandwagon
4. I have an impeccable source
5. I have really good software
6. I am good a creating clever illustrations
7. I have taken requisite spatial data analysis courses
8. It’s the scientific future
9. Accessibly makes it ethical
10. There is no need to sample

He then asked: what is the role of spatial scientists in the big data revolution? He says our role is to find relationships in a spatial setting; to develop technologies or methods; to create models and use simulation experiments; to develop hypotheses; to develop visualizations and to connect theory to process.

The summary from his talk is this: Start with a question; Differentiate excitement from usefulness; Appropriate scale is mandatory; and Remember more may or may not be better. 

When Dr Getis finished I made a quick run down the hall to hear the end of the living legend John Jensen’s talk on drones. This man literally wrote the book on remote sensing, and he is the consummate teacher – always eager to teach and extend his excitement to a crowded room of learners.  His talk was entitled Personal and Commercial Unmanned Aerial Systems (UAS) Remote Sensing and their Significance for Geographic Research. He presented a practicum about UAV hardware, software, cameras, applications, and regulations. His excitement about the subject was obvious, and at parts of his talk he did a call and response with the crowd. I came in as he was beginning his discussion on cameras, and he also discussed practical experience with flight planning, data capture, and highlighted the importance of obstacle avoidance and videography in the future. Interestingly, he has added movement to his “elements of image interpretation”. Neat. He says drones are going to be routinely part of everyday geographic field research. 

What a great conference, and I feel honored to have been part of it. 

March was busy month for the IGIS team. We started out with only one member of our group (Sean Hogan) being a FAA certified drone pilot, and ended the month with the rest of the team - Maggi, Shane, Robert, and Andy - having also obtained their FAA Remote Pilot License with sUAS Rating.

A FAA remote pilot license is required to fly drones legally for any non-recreational purpose (which includes basically everything we use drones for in ANR and UC). The 'hard' part of obtaining your drone pilot certificate is passing a 60 question FAA Airman General Knowledge exam, which covers a broad range of topics related to the safe and legal operation of drones in the national airspace. Our efforts to get certified were propelled forward by an excellent FAA exam prep-class offered in early March by UC Merced Extension, and taught by Andreas Anderson, a long-term pilot and graduate of the UC Merced MESA lab.

Our programmatic goal in getting more certified drone pilots is to help serve the growing demand for drone services in the Division, including both flying missions and training. Flying safely and legally however is only the start. Using drones effectively as data collection platforms for research and extension takes a host of other skills and knowledge, including mission planning, flight operations, using the equipment, data management, and select principles of photogrammetry and remote sensing. This is why we encourage everyone in ANR interested in using UAVs for their research or extension programs to attend one of our Drone workshops, such as the upcoming workshops at Kearney REC (April 13-14), UC Berkeley (Apr 2 ), Quincy (June 7-8), or our three-day Dronecamp at the end of July (application deadline April 15, 2017). Need some inspiration how drones might be useful in your work? Check out the current issue of Cal Ag which features a number of applications of drone science for agriculture and natural resources.

IGIS is pleased to announce a three-day "Dronecamp" to be held July 25-27, 2017, in Davis. This bootcamp style workshop will provide "A to Z" training in using drones for research and resource management, including photogrammetry and remote sensing, safety and regulations, mission planning, flight operations (including 1/2 day of hands-on practice), data processing, analysis, and visualization. The workshop content will help participants prepare for the FAA Part 107 Remote Pilot exam. Participants will also hear about the latest technology and trends from researchers and industry representatives.

Dronecamp builds upon a series of workshops that have been developed by IGIS and Sean Hogan starting in 2016. Through these workshops and our experiences with drone research, we've learned that the ability to use mid-range drones as scientifically robust data collection platforms requires a proficiency in a diverse set of skills and knowledge that exceeds what can be covered in a traditional workshop. Dronecamp aims to cover all the bases, helping participants make a great leap forward in their own drone programs.

Dronecamp is open to all but will have a focus on applications in agriculture and natural resources. No experience is necessary. We expect interest to exceed the number of seats, so all interested participants must fill in an application before they can register. Applications are due on April 15, 2017. For further information, please visit http://igis.ucanr.edu/dronecamp/. Dronecamp Flier.