Yet, someday, astronauts will want a fresh salad with tomatoes on those long, two-year missions to Mars that President Bush is planning. So NASA asked the Ohio Agriculture Research and Development Center to develop a robotic tomato harvester.
Agriculture engineer Peter Ling and his team took the $100,000 NASA grant and built a robot that can identify a ripe tomato, zero in and pluck it from the vine. All in 3 1/2 minutes.
The delicate tomato is a perfect test subject.
“It’s fragile,” said Ling, an Ohio State University researcher. “If you can harvest that, you can also harvest citrus and apples.”
Maybe NASA hasn’t grown a tomato in space yet, but if a robot can pick a good one, it could do a lot of other work, said Terri Lomax, a senior adviser for research at NASA headquarters in Washington, D.C.
Besides tomatoes, lettuce, sweet potatoes, potatoes and soybeans likely will be part of the life-support system for spaceships and moon buildings.
“If you were going to be locked up in an enclosed system for a long time, wouldn’t you want a ripe tomato with you?” said Kennedy Space Center agricultural engineer John Sager. Plants will generate oxygen, absorb carbon dioxide from the air, take care of waste, purify water and generally give space quarters that homey feel.
The robot, which is pushed around Ling’s lab on a low-tech metal cart, consists of an electronic eye, a small industrial robotic arm and a cagelike appendage that plucks the fruit and drops it into a basket.
“They showed we could do it: Locate the fruit, go into the vine and find it,” Sager said. “That’s not a trivial task.”
First, the eye senses the tomato by its roundness and color, then the arm moves in. A small suction cup pulls the fruit away from the vine, and the cage opens and closes around the fruit. More than 95 percent of the time the robot can identify the fruit, and more than 85 percent of the time, successfully pick it. That’s not, however, as good as a person.
“Humans can identify a tomato 100 percent of the time and harvest better than 95 percent,” Ling said.
But in space, humans will be busy doing other Final Frontier stuff, such as research and exploration. Captain James T. Kirk never picked a tomato in his life.
Ling, whose team squished a lot of tomatoes getting it right, said the robot will need to be improved before it’s truly ready for space. He said reducing the plucking time to 20 seconds is a reasonable goal.
Ohio State’s harvester is more likely to find its first job on Earth. Ling has received some calls from growers in Arizona, Florida and Holland.
Copyright 2004 The Columbus Dispatch
Copyright © 2002 LexisNexis, a division of Reed Elsevier Inc.