Picture a swarm of tiny robots moving down rows of cotton, mechanical spider arms plucking multiple bolls each second and depositing fiber into holding containers. Ginning begins immediately in the containers, and the bots move on to more plants.
Robotic harvest is knocking on the door of traditional row crop production, and cotton growers might bring in the first fruits. A massive technological push steered by Cotton Incorporated aims to deliver automated harvest via fleets of swarm robots to U.S. fields within 10 to 15 years. Coordinated field research is underway in multiple states, and the results might benefit all of U.S. agriculture.
A commercial prototype could be ready in just over a decade, according to Ed Barnes, senior director of agriculture and environmental research for the company. Weaving together technological development projects across the Cotton Belt, Barnes hopes to fundamentally impact the dynamics of cotton production by opening the door to small acreage growers, lowering overall costs and improving lint quality.
The field math is crucial: Right now, top cotton pickers run at 5.5 mph and cover 8 to 10 acres per hour. Barnes estimates a single bot could run at
3 mph and cover 11 acres per day picking one boll every three seconds. Cotton plants mature from bottom to top. Open bolls can sit 40 days at harvest, exposed to the elements and subject to degradation. Barnes believes swarm bots could pick fiber in multiple mini-harvests as bolls open. (A trial is slated this year to conventionally harvest every other day to gauge the effect on fiber quality.)
Assume one acre holds 1,500 lb. of fiber. A single bot, collecting 60 lb. of fiber each trip, would pick the acre 25 times per harvest cycle. The overall harvest would extend to approximately 50 days, Barnes projects. “We’d stretch harvest out, but it would be much more efficient, with less time for a boll to get blown or washed off,” he notes.
“The technology to do all these things is already here,” he adds. “We want to piece it together.”
What is a reasonable target cost for a swarm bot? The starting retail cost for a module-building John Deere picker is around $900,000. Barnes is hoping to get costs allocated to harvest down to $4,000 per bot, which would allow access for small to medium operations: 200-plus acres, 20 bots, $80,000; 500 acres, 50 bots, $200,000.
Such tools offer value beyond cotton harvesting, Barnes notes. “Weed control, phenotype measurement, pest scouting and harvesting additional crops are strong possibilities to further justify ownership.”
Glen Rains, a University of Georgia agricultural engineer, is working on a prototype to identify bolls at real-time speed and harvest with a vacuum tube. Rains is using an articulated rover made by West Texas Lee that is customized to allow for add-on electrical components.
Roughly the size of a 50-hp tractor, the two-row rover is highly adjustable and easily raised. A hydrostatic drive and 25-hp engine turn hydraulic pumps. In front, a stereo camera looks down at bolls and feeds data back to a computer, which controls an arm to extract fiber. The rover will eventually be equipped with one arm per row.
In a two-step process, the camera determines boll location and then boll stage. It seeks a certain amount of light in an image that specifies whether the boll is ready to pick. Currently, the rover can identify bolls at 1 mph, but Rains expects big increases in processing power.
Rains estimates the rover might eventually pick three bolls per second: “Ultimately, a lot of the capability depend on cost of operation. A multipurpose machine changes the cost structure. Also, certain varieties with different boll density might be more conducive to this type of harvest.”
Another major spoke on the research wheel, Joe Mari Maja, an electrical and computer engineer with Clemson University, is testing the physical components of automation, aiming to add harvester mechanisms to a single-row Husky robot platform. “We’re going to find out what picking technology works best. Possibly a vacuum tube, spinner technology or multiple picking arms; maybe a combination of the three,” he says.
Maja has begun field tests, adding sensors and extending battery life. “This is a holistic approach that will go far beyond cotton. There is going to be genuine robotic harvesting for all crops in the near future,” he says.
At Oklahoma State University (OSU), agricultural engineer Mike Buser is pulling hard on the research rope to develop an unmanned ground vehicle to run cotton rows in search of plastic contamination, a thorn for the industry. Under Buser’s tutelage, OSU research engineer Collin Craige is creating an unmanned ground vehicle to operate as a robot lumberjack to seek and cut down eastern red cedar trees located by unmanned ground vehicle flyover scans.
“A UAV [unmanned aerial vehicle] can pinpoint the location of contaminants, and then this location can be relayed to a ground-based bot that will go and retrieve the contamination, Buser notes. “We could use a swarm of bots for all sorts of tasks beyond contamination retrieval or harvest. They could be used for weed, pest and disease control, or even nutrient management down the road.”
Cotton Incorporated is expanding research to test robotic ginning and in-field separation of seed and fiber at Texas A&M University. In addition, specialists at Kansas State University are set to begin an economic analysis of all factors surrounding a swarm bot system. The entire swarm bot harvest project will be at full-bore this year, according to Barnes.
Promising technological leaps are easy fodder for naysayers and deemed as perpetual pipe dreams—until they arrive and suddenly become part of standard practice. “Twenty years ago the current round baler was hard to envision for anyone in agriculture. Just a little over 10 years back, nobody out there even knew what an iPhone was,” Barnes concludes. “Change is coming to farming, and it will get here fast.”