Harvest help of the future

Photos Courtesy of Vision Robotics Corp.
This is an artist’s depiction of the robotic vineyard pruner mounted on a tractor.
Vision Robotics’ apple scout in an orchard.

Visual acuity built into a robotic system may be the key to solving today’s harvesting problems. With labor more difficult to secure, gathering crops such as apples, grapes and oranges, among others, has become a big challenge, but a developing technology may bring a whole new way to harvest.

The vision difference

The notion of mechanical and robotic harvesting systems isn’t new. Machines are harvesting a variety of crops including grapes and blueberries. Derek Morikawa, chief executive officer of Vision Robotics Corporation (VRC; www.visionrobotics.com), says some existing equipment has its drawbacks. For instance, orange harvesters that remove fruit by shaking the branches or canopy of trees often damage the fruit. While that is acceptable for juice oranges, it isn’t appropriate for fresh fruit. With varieties such as Valencia that produce on two-year cycles, such equipment may remove the immature fruit that will form the next year’s crop. Although mechanical platforms that move human pickers through apple orchards are being considered, the possibility of damage has largely prevented apple growers from investing in harvesting machines. VRC technology will address those issues, but the additional features it plans to incorporate make its future offerings something to put on your wish list now.

Developing agricultural applications

VRC was formed in 1999 and is developing systems for a variety of applications. It has patented autonomous vacuum cleaners and personal service robots, which the company expects to perform not only household chores, but also to be integral in the future of healthcare and eldercare. The San Diego-based firm is collaborating with the Space and Naval Warfare Systems Center, also located in San Diego, on a stereo vision mapping system for future military use.

VRC began tackling agricultural challenges about five years ago at the suggestion of a board member, who happens to be an orange grower and was all too familiar with labor difficulties. Harvesting accounts for 50 percent of orange growers’ labor needs, so a worker shortage can be devastating.

(Above Left) Vision Robotics’ apple scout is tested in a California orchard. (Below Left) A Vision Robotics robot prunes a grape vine. (Above) This is how a scout robot and harvester robot could work in an orange grove.

The VRC team, including Bret Wallach, robotic technology guru and company founder and president, visited the groves and reviewed previous attempts at mechanical harvesting.

“People have tried robotic harvesting since the mid-1980s,” Morikawa says. “The problems have been that they could only pick 65 to 75 percent of the crop and were too slow to compete with people picking.” He adds that previous models were equipped with a robotic arm and camera and picked only one fruit at a time. The largest difficulty was that the camera detected oranges randomly, sending the robot first in one direction and then another without completely harvesting each section.

VRC’s breakthrough that solidified its commitment to the agricultural market was in overcoming those obstacles. With the support of the California Citrus Research Board, the company proved that all the fruit can be seen from outside the tree. This led to the development of a scouting robot that scans an entire tree and locates all the fruit. The scout relays a map of the fruit to a harvesting robot outfitted with multiple arms. From that data, the harvester does some mathematical magic to determine the most efficient pattern for collecting the oranges.

“It reaches more than 95 percent of the fruit very effectively,” Morikawa says. “We have tested all of this in the field and we know that we can produce this system economically.” Presently, an 8-foot scanning arm is being developed for use in orange groves.

VRC also is working with the Washington Tree Fruit Research Commission to create a harvesting tool for apples. Morikawa says that densely planted orchards with highly visible fruit means that the apple product will be less complicated to develop. Although it will differ from the orange harvester, the same concept of scouting and picking robots will be incorporated. In discussions with grape producers, the firm is proposing a robotic pruning product, in which the apple industry also has expressed an interest. By employing the scanning or scouting function, the optimal pruning procedure can be determined.

Overall crop management

As important as harvesting and pruning are, those are just the beginning features of the farmer robot. With its intelligent scanning eye, the robot has the potential to become a new overall crop management tool that could take agriculture to an unprecedented level of sophistication.

“The scout is actually a data gathering robot,” Morikawa says.

The technology can revolutionize agricultural marketing because the scanning function can predict the future for a grower. Early in a season, crops can be evaluated robotically to measure ripening speed and make harvest estimates. As the crop matures, the robot can determine exactly how many fruits there are and even break the number down by grades. This type of information will enable growers and marketers to time the market advantageously. In addition, tasks such as evaluating water use and plant health can be delegated to the robot.

“This is a major crop management tool,” Morikawa says. “That is what robotics can do for agriculture.”

Bringing the product to market

Morikawa says the robotic arm element of the agricultural products doesn’t pose a problem, as that component is well developed and working efficiently for assembly lines and packing operations, but the vision system is a largely unexplored area.

“The vision aspect needs a lot of computing power and skill,” he adds. “Seeing green fruit among green leaves is a problem.”

VRC’s trade association partners are funding the research. Two years is the estimated time frame for development of the first component, the scouting robot, with the harvesting one completed two years later. California grape and winery groups are funding the initial stage of pruning machine development. VRC expects to have a prototype in the field during the 2008-2009 winter and the first production prototype the following year. The company’s goal is to prove the robotic concept in the field and then recruit industry packers and large growers to fund development of the end-user product.

“We don’t want to kick people off the farm, but labor is harder to find, so this will help when labor isn’t available,” Morikawa emphasized. “Robots bring a new management system; that’s the vision for robotics.”

The author is a freelance writer based in Greensboro, N.C.