As AgriView Systems, Eric Hendrix and other members of his family operate the only Georgia dealership for AgEagle, a Kansas company that makes robotic aircraft, popularly know as drones, specifically for farming applications.
"Right now you would have to get special certification to be a pilot and fly them for people, per FAA regulations, but we do sell them for people to use on their own farms," Hendrix explained.
He and his wife Jennifer brought one of the drones and its launch catapult to the Ag Expo and Farm Market held Saturday at Claxton Elementary School. Actually flying the AgEagle 1, which is a flying wing with a 56-inch wingspan and a pusher prop, was out of the question, with all the people, the exhibitors' tents and nowhere to land.
But Eric Hendrix and Kent Hendrix, brothers, provided a demonstration in a field their family farms near the Bulloch County-Evans County line.
Removing the equipment from the back of an SUV, Kent set up the catapult, a metal beam angled gently upward on a bipod, with a little sled for the plane on top and several tension cords underneath, which are drawn tight one by one and locked into place.
Meanwhile, Eric worked with a laptop computer to plot the flight plan. He also has a controller with joysticks, like those used by radio-controlled plane hobbyists, but this serves only to start the plane prior to launch or to bring it in early, and is not used to control the plane in flight.
Flies by autopilot
Instead, the AgEagle software tells the plane where to fly based on Global Positioning System coordinates. The little planes have flight-speed sensors and gyroscopes and use these to fly by autopilot.
With this particular model, the user preparing for takeoff first needs to set the plane down along path where it will land, to establish the home position for GPS.
But the more sophisticated AgEagle RAPID will fly entirely from the plotting done on a laptop, tablet or smart phone without the need for the preliminary positioning. The Hendrixes have a RAPID but have sent it off for an upgrade to a newer version with carbon fiber laminate coating. The AgEagle 1's airframe is made of a compressed foam-core material with Kevlar and fiberglass on the leading edge and nose.
Kent removed the safety, a big steel pin that prevents accidental release of the catapult. Eric powered the plane's motor up with the remote, Kent put his foot on the release pedal, and the plane was off the end of the catapult in a blink and climbing fast.
The catapult launches the plane at 30 mph, flying speed.
Completing its demonstration run, the plane, which has no wheels or other landing gear, simply flew in low, then dropped on the ground. In tall crops, such as corn, farmers sometimes intentionally let the plane land on top of the crop for retrieval.
In a real farm-related mission, the plane would follow its programming to make parallel "lawnmower passes" over the field while taking one photograph every 1.3 seconds with its digital camera. The photos are timed to overlap.
With the AgEagle 1, the photos are stored on a camera card and downloaded when the plane lands. The images then require "stitching" to create a map of the field, a process that takes hours longer than the flights, which are limited by battery life to 40-55 minutes, enough to cover several hundred acres. The RAPID processes the photos automatically and can upload them to cloud storage over a 3G or 4G network.
Despite similarities, the planes' aerial camera is not identical to a regular digital camera. It's an NDVI camera system, applying the Normalized Difference Vegetation Index to the images. This measurement uses readings of infrared light.
"It shows you how much chlorophyll level there is in the plant, and then that will let you gauge your crop health, so if you have a problem that you find in a field, you can go out and find out what the problem is and fix it before it affects your overall yield," Eric Hendrix said.
In other words, the aerial photography can help identify where pesticides, changes in fertilizer rates or other interventions are needed. Farmers with variable-rate sprayers, guided by GPS, can use the data to create a prescription map to selectively control their use of fertilizers to reduce costs, Hendrix said.
The AgEagle drones fly up to 400 feet high. That's the maximum legal altitude for unmanned aerial vehicles under Federal Aviation Administration rules.
Hendrix submitted comments for the FAA's recent rule-making process for commercial-use drones, and says the rules are very positive for the industry, clarifying what can be done.
He has also advised the Kansas manufacturer on adapting flight patterns for the Southeast with its relatively small fields and abundant trees.
These specialized drones are not cheap. The AgEagle 1 goes for about $14,500; the AgEagle Rapid for $16,500. This comes with on-site delivery and training and a one-year subscription for image processing. Hendrix is not allowed to reveal how many units he has sold, but he said his most recent sale was to Bacon County High School in Alma. Surveyors and people involved in timber and forestry are also customers, he said.