|Photograph courtesy of Yael Eden|
Although today's agricultural machines bristle with computer processors, satellite links, and GPS locators, it's hard to beat human hands for such delicate tasks as picking melons. But industrial engineer Yael Edan and her colleagues at Ben-Gurion University, the Volcani Institute, and the Weizmann Institute of Science in Israel, and Purdue University in Indiana, are willing to try. They've created VIP ROMPER (above), a tractor and picker that guides itself down rows of melon plants with only occasional human steering corrections. The picker incorporates a black-and-white video camera for finding the fruit and a robotic arm that plucks them as the tractor moves. A fan on the arm blows aside the melon plant's large leaves so the camera can see the fruit. Onboard software evaluates the image's shape, brightness, and texture to locate the melons. Then a chemical sniffer determines whether the fruit is ripe. A basketlike gripper on the arm gently grabs the melon, "like a hand folding around it," Edan says, and lifts it as a knife cuts the stem. In field tests, VIP ROMPER correctly identified melons 85 percent of the time. Edan estimates a two-armed version could attain a picking rate of one and a half seconds per melon.