Can Robots Make Farming Greener?

Could agricultural robots change the way we farm? Brian Clark Howard reports from southern Israel.

Photo: Brian Clark Howard

The robotic tractor came to a hard stop just a few feet in front of us. Roughly the size of a Mini, it looked a bit like a NASA Mars rover, with fat off-road tires, yards of hoses and wires and a big yellow tank on top that shone in the midday sun.

A puff of liquid shot out from one of the nozzles, and a gust of wind blew a fine mist into our faces.

“I hope that’s water,” one of the journalists said.

Professor Yael Edan of the Mobile Robotics Lab assured us that it was. The moisture felt refreshing in the heat.

We were standing outside of Edan’s lab at Ben-Gurion University of the Negev in southern Israel. The surrounding region is parched desert — essentially the northeastern part of the Sahara — but the campus is immaculately landscaped, thanks to an integrated system of drip irrigation.

Rubber tubes snake through the flowerbeds and greet the base of each tree, where they “drip” a small amount of water right where each plant needs it, minimizing loss to evaporation and runoff. Drip irrigation was invented by Israelis decades ago, according to the host of our “green campus” tour.

Edan and her colleagues in the Ben-Gurion robotics lab hope to build on the elegant efficiency of drip irrigation by taking the technology into the 21st Century. They hope their agricultural robots will help farmers get better yields while using less pesticides and water. Robots may also help reduce labor costs and protect workers from harmful farm chemicals.

In one sense, Edan’s work seems like the antithesis of the organic movement, which seeks to eliminate industrial pesticides entirely by encouraging plants to become as healthy as possible and by using biological controls. However, it’s easy to envision how agricultural robots might assist large-scale organic farmers as well. The technology could be used to more effectively and efficiently deliver water, natural fertilizers or control agents, and by helping with harvesting and other tasks they could eventually help lower the price of organic foods.

In fact, as Emily Sohn points out on Discovery News, modern commercial farms are already using tractors with automated steering and machines that till soil or milk cows. Robotics isn’t a far stretch from the methods of so-called “precision agriculture,” which uses GPS coordinates and sophisticated software to guide targeted farming.

Sohn, who also visited Edan’s lab, points out that scientists have been building agricultural robots for more than 20 years. But the technology is improving, particularly when it comes to the algorithms that serve as the robots’ “brains.”

“We are developing a robot that sprays vineyards based on the presence of foliage it detects, and it results in an 80% savings in pesticides,” Edan told us. “We are also developing a robot that will spray only individual fruits. We’re aiming at grapes, apples and peppers,” she said.

Edan’s team has already developed a date-spraying device, which saves on labor and reduces accidents on farms, since dates grow high in trees. The team also sells a system (for $100,000) that automatically sprays water, pesticides or fertilizers inside a greenhouse. That product is not yet “smart” enough to adjust outputs based on sensory data, but that’s what the lab is aiming for. In other words, if an individual plant needed some extra attention, or if one part of the greenhouse has already received plenty of water.

Dr. Ohad Ben Shahar and other Ben-Gurion researchers are working on visual modeling, to help robots distinguish individual pieces of produce from surrounding vegetation. That’s not an easy task in the field, which has lots of variability and changing conditions throughout the day and over the seasons. Edan said the group’s bots can now identify between 80 and 85 percent of fruits, but they hope to increase that to 90 percent in the near term, and eventually to 99 percent.

To get there, the robots use multi-spectral cameras that analyze the wavelengths of light bouncing off of objects. Algorithms process the data, and the robots “learn” to do better over time.

“We aim to detect the ripeness of the fruit as well,” Edan said. She added that robotic pickers could be a boon to farmers in areas with a labor shortage, including Israel and parts of Europe.

Dr. Sigal Berman, also of Ben-Gurion, works on improving the grasping ability of robots, so they won’t damage tender fruits or the plants that produce them. “We are going with a simple pneumatic system,” Berman explained.

Berman has developed robotic arms with even more sensitive tolerances for surgery. And she applies similar principles in her work with rehabilitating paralyzed stroke victims. Her team uses the Microsoft Kinect motion-activated video game system for part of their modeling and training work.

Edan said her group’s advanced agricultural robots should be ready for prime time in the next few years, and she added that they should be “affordable” for farmers.

So in a few years, when you bite into a shiny red apple, you may have a robot to thank.

Award-winning journalist Murray Fromson and the American Associates of Ben-Gurion University of the Negev covered the travel expenses of this reporter.