Aerial Application Technology Research Session

NAAA Ag Aviation Expo
Aerial Application Technology Research Session Presentations

December 4, 2017 ♦ Savannah, Ga.



Thank you to Dr. Brad Fritz for organizing the 2017 Session.
10:00 – 10:10: Session Kickoff
10:10 – 10:25: Aerial Imaging with Manned and Unmanned Aircraft, Chenghai Yang, 
10:25 – 10:45: Emerging Technologies in Crop Spraying Using Small Unmanned Aircraft, Wayne Woldt
10:45 – 11:00: Making the USDA ARS Spray Nozzle Models Work for You, Brad Fritz
11:00 – 11:20: The Ideal Emulsion – How to mix and match in the field, Carl Austin
11:20 – 11:40: Custom Application, Custom Pricing, Senarath Dharmasena
11:40 – 11:55: Aerial Applications for Spider Mite Control in Corn, Dan Martin 
11:55: Noon Wrap up and Conclusion, Brad Fritz

Aerial Imaging with Manned and Unmanned Aircraft
Chenghai Yang, USDA-ARS, Aerial Application Research Unit, College Station, TX
In the last few NAAA conventions, we presented several single-camera and dual-camera imaging systems for use on agricultural aircraft. We also offered an aerial image processing workshop at the 2016 convention. In this presentation, we will provide up-to-date information on these image systems and image processing techniques to convert imagery to application maps. Specifically, we will present a new dual-camera system consisting of a Nikon D7100 red-green-blue (RGB) color camera and a modified near-infrared (NIR) camera, a GPS receiver, and a wireless remote control. The dual-camera has been mounted on both a manned aircraft and an unmanned aircraft system (UAS) to acquire images. The advantages and limitations of manned and unmanned imaging platforms will be discussed. We will illustrate how to use the commercial image processing software Pix4DMapper to convert a set of geotagged GRB and NIR images acquired with the two-camera imaging system into georeferenced image mosaics, surface elevation models, normalized difference vegetation index (NDVI) maps and prescription maps for precision aerial application. To help aerial applicators and interested users familiarize the image processing process, we will also offer a two-hour workshop at the 2017 NAAA convention. You will have an opportunity to have some hands-on experience with different camera systems and image processing software.

Dr. Chenghai Yang is an Agricultural Engineer with the USDA ARS Aerial Application Technology Research Unit in College Station, Texas.  Dr. Yang’s research focuses on the development and application of airborne multispectral, hyperspectral and thermal imaging systems for precision agriculture and pest management.  His recent efforts have focused on developing low-cost imaging systems and image processing techniques for aerial applicators and evaluating these systems for mapping crop pests for site-specific chemical applications.  He has authored or co-authored more than 130 peer-reviewed journal articles and serves on a number of national and international professional societies.
Emerging Technologies in Crop Spraying Using Small Unmanned Aircraft
Wayne Woldt, Associate Professor, Department of Biological Systems Engineering, Institute of Agriculture and Natural Resources, University of Nebraska-Lincoln.
Unmanned aircraft systems (UAS) have the potential to benefit agricultural production by offering an unparalleled opportunity to place sensors, robotics, highly precise crop spraying systems, and advanced information systems at specific locations and times, across a diverse and complex agricultural landscape.  A new project focused on small UAS (sUAS) enabled crop protection systems has been initiated at the University of Nebraska. It is envisioned that sUAS technologies will be a “force multiplier” for the agricultural aviation industry, in which small infestations, edge stress, and very early intervention efforts are achieved by sUAS. In the longer term, the potential exists to advance the concept of ultra precise agriculture enabled by unmanned aircraft and robotic technologies. In this case, small UAS (sUAS) are defined as less than 55 lbs. maximum take-off weight. Initial collaborations are being formed to develop research and education efforts around multiple topics:
  • Standards and performance verification in support of the agricultural aviation industry (i.e., ASTM and ISO)
  • Policy, law, and regulation development and analysis (i.e., product label, Part 137 operations, and application regulations)
  • Ultra precise application of herbicides and pesticides (i.e., space/time resolution and economic threshold for crop spraying)
  • Unmanned aircraft spray techniques and performance (i.e., efficacy of the application systems under dynamic environmental conditions)
The concept of UAS in ultra-precise agriculture has resulted in the formation of a trans-disciplinary team at the University of Nebraska, to explore, and characterize an array of opportunities.  The initial partnership and collaboration, includes: Agronomy and Horticulture (Greg Kruger and Christopher Proctor), Biological Systems Engineering (Wayne Woldt), Plant Pathology (Tamra Jackson-Ziems), and Entomology (Robert Wright and Justin McMechan), along with both Campus and Center involvement.

Wayne Woldt, Ph.D., P.E., is an Extension Specialist at the University of Nebraska, in the Department of Biological Systems Engineering and the School of Natural Resources. He has been at UNL for 26 years, and has developed a research and extension program on the application of unmanned aircraft systems. General areas of interest include: agriculture, UAS flight safety, and land mapping. Specific areas of research and education include: crop spraying with small unmanned aircraft systems, development of a safety beacon for UAS flight operations, development of active UAS sensing technologies for agriculture and natural resources, deployment and flight operations of unmanned aircraft systems, and performance of autonomous navigation systems.  Wayne has been flying unmanned aircraft for the past 5 years, and obtained the first FAA issued Certificate of Authorization to fly unmanned aircraft in Nebraska.  His pilot ratings include private, remote, glider, and hot air balloon, with over 700 hours of total flight time.
Custom Application, Custom Pricing
Senarath Dharmasena, Assistant Professor, Department of Agricultural Economics, Texas A&M University; Dan Martin and Stephen Cain
 Current day agricultural aircraft operations are an expensive enterprise with many participants competing for spray jobs. As a result, small differences in the price charged per acre per job could keep an applicator in or out of the business. Questions that linger in applicators’ mind would be; what is the best price to charge? What is the desired profit margin for a spray job and business? Would there be range of prices one can work with for a spray job? Is the current profit margin enough to cover the next big purchase or to overcome unforeseen contingencies? What is the aircraft operating cost per hour and how does that factor into the equation? Does the current profit margin cover all or most of the expenses? and Does the price per acre represent the price per job? Although the revenue side of the profit calculation is fairly simple (price per acre per job times the number of acres sprayed/applied), the cost side is not. It includes fixed expenses such as aircraft, facilities, other equipment, and insurance. Variable expenses are fuel, aircraft and runway repair and maintenance, labor, and taxes and ferry costs. The variations in aircraft fuel prices and equipment costs along with other expenses could adversely affect the revenue and profit margins of the operators. Also, one cannot overlook the other risk factors associated with the application such as obstacles, sensitive crops, other dwellings, aircraft turnaround times, and unanticipated mechanical problems. Consequently, precision pricing of the service is crucial to achieve the desired level of profit. Several scenarios are demonstrated to show the pricing strategies under unique circumstances: (1) The effect of charging the same price per acre across all fields, (2) How much one has to charge to make a 20 percent profit across all fields, (3) Two different shaped fields at different distances from the operation, and (4) Risk factors associated with the application. Once the economic model has been developed, it can be modified to fit the unique characteristics of nearly any other aerial application operation. This will lead to the development of an economic model for different aerial application operations, by region, since cost and business practices associated with different regions can be considerably different. Eventually, design and development of a Big-Data software application, such as a phone app will be explored. This will be useful for applicators in the aerial application industry with regards to precision pricing and ultimately to achieve the desired profit margin for the business to stay viable.

Currently, Dr. Dharmasena is Assistant Professor, Department of Agricultural Economics, Texas A&M University. Also, he is Associate of the Agribusiness, Food and Consumer Economics Research Center (AFCERC) at Texas A&M University.  Dr. Dharmasena’s current research interests are in the areas of Consumer Economics and Applied Demand Analysis, Agribusiness and Food Market Analysis, Behavioral Economics, Health and Nutrition Economics, Economics of Food Security, Food Environments and Obesity, Causality Modeling, Probability Forecasting and Forecast Evaluation, and Market Integration and Price Discovery. He is an expert in applied econometric modeling. He has published in leading peer-reviewed journals including Empirical Economics, Health Economics, Food Policy, Agricultural and Resources Economics Review, Journal of Agricultural and Applied Economics, Journal of Agricultural and Resource Economics, Energy Economics, Journal of Food Distribution Research, and Resources, Energy and Development. He is member of several national and international professional associations including, Agricultural and Applied Economics Association, Western Agricultural Economics Association, Southern Agricultural Economics Association, National Agri-Marketing Association, and Northeastern Agricultural and Resource Economics Association.
Aerial Applications for Spider Mite Control in Corn
Dan Martin and Ab Latheef, USDA-ARS, Aerial Application Research Unit, College Station, TX
Spider mites cause extensive damage to field corn, feeding on the underside of the corn leaves. Spray coverage on the under sides of plant leaves has proven difficult with conventional spray applications. Previous research has shown that electrostatic spray applications can provide superior spray deposition on the undersides of plant leaves. A field study was conducted in Kansas to compare efficacy and deposition from an electrostatic and a conventional flat fan spray application for control of spider mites on mature field corn. Results of this study will be presented to provide spray application guidance to aerial applicators.

Dr Martin is a Research Agricultural Engineer with the USDA-ARS Aerial Application Technology Research Unit in College Station, TX. Prior to his tenure with ARS, he directed the aerial application extension program in Louisiana for 10 years, working one-on-one with aerial applicators as an Operation SAFE Analyst and Extension Educator. Currently, he conducts variable rate and electrostatic aerial application research. He is an active member of several professional societies and serves on numerous technical committees. He has authored over 30 refereed publications.
Making the USDA ARS Spray Nozzle Models Work for You
Brad Fritz, USDA-ARS, Aerial Application Research Unit, College Station, TX
Many aerial applicators are already familiar with the USDA ARS Aerial Spray Nozzle models, either in their smartphone or Excel based interface format.  These models allow you to quickly determine the droplet size of your applied spray based on the type of nozzle you are using along with how you are using it.  These models provide a tool to quickly assess how changes in nozzle type, size and orientation, as well as changes in spray pressure and airspeed impact the spray quality of your application.  However, changes in these parameters typically change your spray rate as well, requiring some iteration on the part of the user to find the ideal combination of parameters that provide both the correct droplet size and applied spray rate.  This can, at times, be a time-consuming and potentially confusing process.  To make these models work for you, nozzle flowrate data and spray rate calculations have been added to give you not only the droplet size data but the required number nozzles needed for a desired spray rate.  Additionally, a couple of new interfaces provide users with the ability to see all potential nozzle types and operational setups that provide a specified droplet size class and applied spray rate, streamlining the nozzle selection and setup process for your specific application.  While these new formats and interfaces were featured in a recent issue of Agricultural Aviation, as well as in the current PAASS program, we will take a closer look at how these models work and how you can make them work for you.

Dr. Brad Fritz is an Agricultural Engineer with the USDA Agricultural Research Service, Aerial Application Technology Research Unit, a group tasked to research all aspect of aerial application technology.  Dr. Fritz’s early research efforts centered on the role atmospheric conditions, such as stability and inversion, played in the movement and ultimate fate of aerially applied sprays with the goal of maximizing on-target deposition with minimal downwind loss.  Current research focuses on the role nozzles and spray formulations play in the formation of droplet size and has led to development of new fixed and rotary wing spray nozzle models and enhanced user-interfaces for applicators.  Dr. Fritz actively participates in a number of professional organizations and continues to regularly publish and presents his research findings through a number of peer-reviewed journals and national and international meetings.
The Ideal Emulsion – How to mix and match in the field.
Carl Austin, Expert Consultant on Plant and Disease Control – Tropical Agriculture
In an ideal world, aircraft would spray crop emulsions that had been perfectly optimized in the lab for stability in the tank and for efficacy on the leaf. In the real world, decisions have to be taken in the field about which combination of formulations are required for the specific conditions on that day. The inevitable mixing and matching of AIs, oils, emulsifiers and other adjuvants can lead to unexpected problems with, at worse, total separation within the tank of oil, water and AI.
By using the well-validated HLD (Hydrophilic-Lipophilic Difference) technique for controlling how emulsification behaviour changes with each formulation ingredient, it is possible, even under field conditions, to tune the day's mix of ingredients to balance an optimal stability in the spray tank with behaviour of the drops on the leaves. It is equally possible to rationally tune formulations for a change of oil depending on the Pest / Crop scenario and galvanize the efficiency of specialized spray systems e.g. Electrostatic.
Here we describe how to combine some key lab-based measurements of oils, emulsifiers and AIs with in-the-field formulation techniques and visual checks to achieve a practical optimum that will ensure AI performance, and reduce the consequences of spraying an unsuitable formulation.

Speaker Bio: Carl Austin is a Bio Aeronautical graduate from Cranfield University whose career has encompass the full supply chain of Banana Production and Commercialization. His expertise is recognized for the management OF Black Sigatoka control in Banana in particular: the characterization of Ag-Aircraft spray patterns; the implementation of novel control strategies that link disease epidemiology to infection forecasting & fungicide mode of action. His latest work has focused on the use of mineral crop oils and the role of emulsion stability on the bioavailability of the active ingredient on the leaf surface.  His work covers consultancy roles to include: Transnational Corporations / F.A.O. / World Wildlife Fund (WWF) and the European Union Commission & Belize Government.

Didn't make it to a previous NAAA Convention? Click the links below to review the previous ASABE Technical Session Presentations.

2016 Aerial Application Technology Research Presentations