Vision Robotics is developing a machine to trim grapevines in the fall.

Image: Vision Robotics As if the debate over immigration and guest worker programs wasn't complicated enough, now a couple of robots are rolling into the middle of it.

Vision Robotics, a San Diego company, is working on a pair of robots that would trundle through orchards plucking oranges, apples or other fruit from the trees. In a few years, troops of these machines could perform the tedious and labor-intensive task of fruit picking that currently employs thousands of migrant workers each season.

The robotic work has been funded entirely by agricultural associations, and pushed forward by the uncertainty surrounding the migrant labor force. Farmers are "very, very nervous about the availability and cost of labor in the near future," says Vision Robotics CEO Derek Morikawa.

Agricultural groups hope Vision Robotics can build this harvester to replace labor crews.

Image: Vision RoboticsIt's a surprising new market for Vision Robotics, which had been focused on developing consumer devices, including a robotic vacuum cleaner to compete with iRobot's Roomba.

When a member of the California Citrus Research Board approached the company in 2004, Morikawa was doubtful that an effective robotic picker was even feasible. A citrus grower brought the skeptical engineers to an orange farm in California's fertile Central Valley, where they walked down the neat rows of trees and stared at the oranges hanging in the branches.

Previous attempts at making a mechanical harvester were thwarted by inefficiency, explains Morikawa. In the past, experimental machines approached a tree as a human would, picking one piece of fruit and then looking for the next. In this slow process, the machine circled the tree repeatedly until it was sure it had picked all the fruit.

Morikawa says his engineers had their breakthrough idea right there in the orange grove. They realized that the task could be divided between two robots: One would locate all the oranges, and the second would pick them. "Once you know where all the fruit is, then it becomes an easy job to calculate the most efficient way to pick it all," says Morikawa.

The eight-armed orange harvester will strip ripe fruit from trees.

Image: Vision RoboticsBut it wasn't just technological challenges that held back previous attempts at building a mechanical harvester –- politics got involved, too. Cesar Chavez, the legendary leader of the United Farm Workers, began a campaign against mechanization back in 1978.

Chavez was outraged that the federal government was funding research and development on agricultural machines, but not spending any money to aid the farm workers who would be displaced. In the '80s, that simmering anger merged with a growing realization that the technology was nowhere near ready, and government funding dried up.

This time around, growers' associations are funding the research. By the end of this year, the orange growers will have invested almost $1 million in the project, says Ted Baskin, president of the California Citrus Research Board. He estimates that it will take about $5 million more to get to the finished product.

The farmers are willing to pay up because they've been rattled by a labor shortage over the past few years – California growers tell horror stories of watching their fruit rot on the trees as they waited for the picking crews to arrive. Last fall, growers rallied in front of the U.S. Capitol, frustrated that Congress still hadn't created a program to ease the passage of foreign guest workers across the Mexico border.

With the supply-and-demand equation uncertain, growers see the robots as a better option. "You can predict what it's going to cost to buy a machine and maintain it," says Baskin. "You can't predict the bargaining that we go through with contract labor," he says.

The two robots would work as a team: one an eagle-eyed scout, the other a metallic octopus with a gentle touch. The first robot will scan the tree and build a 3-D map of the location and size of each orange, calculating the best order in which to pick them. It sends that information to the second robot, a harvester that will pick the tree clean, following a planned sequence that keeps its eight long arms from bumping into each other.

The Vision Robotics engineers are currently building the scout. They expect to have a prototype ready next year, with the harvester to follow two or three years later. Baskin says he doesn't expect the mechanical systems to pose any serious problems. The hard work is writing the software. After the scout robot makes a 3-D map of the tree, it has to evaluate each piece of fruit. What size is the orange? What color is it? Does it have black spots on it? "It's a question of gathering the information, and then judging whether it meets the parameters that are equal to a good orange," Baskin says.

Vision Robotics has been working on that problem for almost four years now, which might give some reassurance to human pickers. The United Farm Workers' leaders say they aren't worried about the robots, because they don't believe the machines will ever be able to do the job as well as people. Spokesman Marc Grossman predicts that mechanical hands will damage the fruit and make it unappealing for supermarket shoppers. "There are already machines that will pick wine grapes, but the high end wine growers don’t use them, because they want the quality," Grossman says.

Farmers don't seem to share that concern. The Washington Tree Fruit Commission started investing in the project last year, and Vision Robotics is talking to other agricultural groups with crops ranging from cherries to asparagus.

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