Sep 5, 2013

Remote-controlled aircraft spray, perform other tasks

Researchers are working with farmers to study the potential of Unmanned Aircraft Systems (UAS) to manage crops and improve yields.

Also known as drones, UAS aren’t viewed positively by many in the United States, but supporters – including those conducting studies at Kansas State University, Oregon State University, the University of California, Davis and other universities – are attempting to change any hostile perception toward the emerging technology.

Advocates of the peaceful application of UAS within the United States might face significant public opposition. Since Congress passed a bill that will open airspace to drones by 2015, at least 42 states have proposed legislation preemptively limiting their use.

The value of UAS on farms was shown in early July at a demonstration at Kansas State University. Researchers at KSU are using UAS to create precise maps of nitrogen deficiencies in soil to help farmers apply fertilizer where it is needed most. The aircraft will allow farmers to map out their fields using infrared imagery to detect how the crop is growing.

Representatives from KSU, as well as the Association for Unmanned Vehicle Systems International (AUVSI), flew drones and allowed the public to handle them while emphasizing the potential for UAS to be economic drivers. A study released by AUVSI in March stated that the unmanned aircraft industry could produce up to 100,000 new jobs and add $82 billion in economic activity between 2015 and 2025.

“(The study) found that agriculture will make up 80 percent of the market for UAS,” said Melanie Hinton, senior communications manager for AUVSI, a Washington, D.C.-based organization that promotes the unmanned systems and robotics community.

“Farmers are just beginning to use this technology in precision agriculture, and researchers are still developing new applications. UAS hold tremendous potential to revolutionize agriculture, and we need to ensure that farmers have this technology available to them. Precision farming is the future of agriculture, and farmers are interested in applying this technology to both increase yields and reduce their environmental impact.”

A project was conducted earlier this year at Oregon State University, in which two small, remote-controlled aircraft were flown over potato fields as part of OSU’s efforts to help farmers more efficiently use water, fertilizers and pesticides to bolster yields and cut costs.

While taking photographs, the aircraft flew over 50 acres of OSU’s 300-acre Hermiston Agricultural Research Extension Center (HAREC), as well as several crop circles totaling about 1,000 acres at a nearby research cooperative farm.

According to a news release, OSU researchers used various cameras on the aircraft to photograph the potato plants.
“The key is to pick up plants that are just beginning to show stress so that you can find a solution quickly, so the grower doesn’t have any reduced yield or quality issues,” said Phil Hamm, the director of HAREC. “This in turn can save money. It’s an early warning system for plants with issues, as well as an opportunity to reduce costs by being more efficient in water and fertilizer use.”

A HawkEye aircraft, sold by Tetracam, is being used in OSU’s project over its own land. About the size of a suitcase and weighing only 8 pounds, its maximum flight is only 10 to 30 minutes. A delta-winged aircraft made of plastic foam was used to fly over the private farm. Called a Unicorn, it has a wingspan of no more than 6 feet and weighs less than 6 pounds.

Recognizing concerns about privacy, Hamm said, “These unmanned aircraft are for agricultural research only and will be used for nothing more than that. This is about helping our local growers do a better job of growing crops.”

In California, a remote-controlled helicopter, fitted with a spray applicator system, was being field tested over hard-to-reach vineyards in Napa Valley by engineers with the University of California (UC), Davis, and Yamaha Motor Corp. The project, to conclude in late summer, included a public display for winegrape growers in June.

For 20 years, the motorcycle-sized RMAX helicopter has been used to spray rice fields in Japan. It’s now being tested for potential agricultural uses in the United States, in areas where aerial applications could prove to be safer and more efficient than tractor use.

UC Davis is one of the few universities in the nation with a Federal Aviation Administration permit to apply sprays with remote-controlled aircraft. That permit applies only to specific agricultural areas, including the UC Oakville Station.

No flights are made in the vicinity of the Davis campus.
Ken Giles, a UC Davis agricultural engineering professor and lead researcher on the project, said in a news release that FAA regulates use of all remote-controlled aircraft.

The craft is flown via a radio signal from a hand-held controller, which closely resembles controllers for miniature hobby aircraft. It can carry slightly more than 4 gallons of water or liquid spray.

Preliminary data found thorough coverage across the vineyard and that air currents stirred up by the helicopter rotors caused the spray to reach even the undersides of the grapevine leaf canopy. The researchers were impressed by the stability of the helicopter, even in gusty winds, according to the news release.

Initially, only water was sprayed, as the researchers explored how well the aerial applicator would cover the vineyard. Eventually, the research team plans to conduct application tests with commonly used agricultural pesticides and herbicides. They want to compare the helicopter to a tractor-drawn sprayer to gauge operator safety, cost and efficiency.

Despite hilly terrain in the region, the mini-helicopter can go where a standard-sized helicopter or fixed-wing aircraft could not venture.

Giles noted that some winegrape growers have expressed interest in using the helicopter to take aerial photos of their vineyards, to identify sites where the vines need special care, or to better determine the optimal harvest time.

Giles acknowledged that the use of remote-controlled aircraft has been receiving public scrutiny.

“As a citizen, I share those reservations and agree that we need to be very careful about how we use unmanned aircraft,” he said. “But with the color, size and noise of a motorcycle, this helicopter that we’re testing is anything but stealthy and would be a great disappointment to anyone hoping to use it for espionage or other covert purposes.

“And, our work is being conducted with the anticipation that the aircraft would be flown by the landowner or by someone hired by the landowner,” Giles said. “That person would want the aircraft to be flying over his or her land.”

– Gary Pullano