Unmanned “Unplugged”

David Schmale, Virginia Tech

The Schmale Lab at Virginia Tech is pioneering new research using Unmanned Aircraft Systems (UAS) technology to study how microbes travel through the atmosphere. With this research, the team is developing strategies to detect, monitor and control pathogens that are harmful to humans and livestock. The lab’s work combines UAS with advanced technology in biology, pathology and genetics to do its innovative research. Unmanned Unplugged recently caught up with David Schmale, an Associate Professor at Virginia Tech and the founder of the lab, to discuss how his team is using UAS.

Tell us about recent projects you have completed with the help of UAS.

We have developed and implemented autonomous UAS to peer into the life of microorganisms traveling hundreds of meters above of the surface of the earth. This new technology was published in the Journal of Field Robotics in 2008. We have discovered that important pathogens of plants, animals, and humans are transported tens to hundreds of kilometers via invisible atmospheric waves known as atmospheric transport barriers. These atmospheric waves collect, mix, and shuffle microorganisms across states, countries, and even continents.

How have unmanned aircraft been beneficial to your research? What are the advantages of using unmanned aircraft instead of manned aircraft for your research?

The movement of microorganisms in the atmosphere is characterized by three main processes: liberation (takeoff and ascent), horizontal transport (drift), and deposition (descent and landing). The process of horizontal transport has largely been understudied, in part due to the lack of appropriate tools to sample the lower atmosphere for microbes. Though full-scale aircraft (e.g., airplanes and helicopters) have been used to sample microorganisms in the lower atmosphere, these aircraft are expensive to operate and risk at least one human life during their operation. We have used UAS to help address these knowledge gaps; to perform ‘dull, dirty, and dangerous’ sampling missions without the risk to human life.

As UAS technology continues to develop, how do you foresee it being used by researchers in the future?

Research efforts in the Schmale Lab are centered on the development of new technology –  UAS to study microbial life in the atmosphere – and the implementation of this new technology for discovery of dangerous microorganisms surfing on predictable atmospheric waves. These efforts have contributed to the burgeoning field of aeroecology. Scientists and policy-makers can use our research to more accurately predict potential outbreaks of disease such as the incorporation of atmospheric transport barriers into meteorological models used through NOAA. Our work has also helped identify new civilian opportunities for UAS, utilizing them to safeguard crop, animal, and human health.

You specialize in researching and studying food safety. How do you envision UAS helping us to protect our food supply? 

We discovered that strains of a fungus collected with UAS hundreds of meters above the ground are able to cause a nasty what disease known as scab (Fusarium head blight). These strains also produce a dangerous mycotoxin (deoxynivalenol or vomitoxin) that far exceeds U.S. food safety threshold levels. This was published in the journal Aerobiologia in 2012.

What led you to begin using UAS for your research? Are there other researchers using UAS for similar projects?

Our research is motivated by the quest for knowledge in the field of aerobiology – the study of the flow of life in the atmosphere. Many microorganisms that threaten the health of plants, domestic animals, and humans are transported over hundreds to thousands of meters in the atmosphere. The ability to track the movement of these microorganisms in the atmosphere is essential for establishing effective quarantine measures and forecasting disease spread. One of the goals of my research program is to understand how microorganisms are transported in the atmosphere. To do this, we’ve developed new technologies with UAS to sample microbes in the air. Autonomous systems have been incorporated into our UAS, enabling teams of aircraft to perform complex atmospheric sampling tasks and coordinate flight missions with one another.

Within the last thirty years, a number of unique UAS including airplanes, balloons, and kites have been used to monitor the movement of microbes in the lower atmosphere. Gottwald and Tedders pioneered the collection of plant pathogens with a UAS in the 1980s. They used a modified remote-controlled biplane platform called the MADDSAP (Microbial Agent Dispensing Drone for Suppression of Agricultural Pests) equipped with two rotating drum samplers to collect spores of plant pathogens over pecan and peach orchards. Nutter and colleagues have equipped tethered weather balloons with spore-sampling devices to collect plant pathogens above crop fields. Mims used kites to collect spores in smoke from biomass fires.

Outside of your research, how do you think UAS will be beneficial to the agriculture industry?

Farmers can use our research to guide the application of appropriate pesticides on their crops, potentially thwarting crop destruction. Data collected with UAS can be used to validate and improve long distance transport models for crop pathogens across local (farm) and regional (state) scales. The commercial development and use of civilian UAS to scout for pests, disease, and nutrient deficiency in crop fields are expected to dramatically increase in the future. This, of course, will be tightly linked to FAA rules and regulations concerning the incorporation of unmanned aircraft into civilian airspace.

Are there research projects you have planned for the future using UAS?

The sky is the limit! One of our new research projects is focused on understanding the role of microorganisms in modulating weather.  Research in the last decade has highlighted the association of microbes known as ice nucleators, which can freeze water at higher temperatures, with clouds, rain, and snow. We will be using UAS to study these ice nucleators in the atmosphere. This project is supported by the National Science Foundation in collaboration with researchers from Virginia, Louisiana, Idaho, Montana and Avignon, France.

We are also interested in educational projects in the future involving UAS. Given the broad appeal of ‘things that fly’ to children and young adults, there are a number of unique, interdisciplinary opportunities involving UAS to excite, engage and train the next generation of microbiologists, aerobiologists and aerospace engineers. Recently, graduate student Renee Pietsch developed and taught a unique interdisciplinary flight unit for advanced high school students at the Roanoke Virginia Governor’s School. This unit was designed to teach students about the principles of flight in biological systems. The unit leveraged the tremendous biological diversity seen in powered flight (birds), gliding animals (flying fish, the colugo, and the draco lizard) and passive transport (microorganisms). These biological systems were then translated through the construction and operation (flying!) of remote-controlled gliders on a beautiful spring day in Roanoke, Virginia.