By Shawn Vestal
Strawberries are delicate and hard to harvest easily bruised and often hidden under a canopy of leaves.
This creates headaches for scientists trying to design robotic harvesters. Now a Washington State University-led team has designed one that combines an artificial-intelligence vision system, soft silicone “fingers,” and a fan that gently move leaves out of the way to get at hidden fruit.
Experiments in the lab and in outdoor fields showed that the harvester correctly detected strawberries 80% of the time, on average, and could classify whether the berries were hidden 93% of the time.
The design, development and testing of the robotic harvester marks a step toward making open-field robotic harvesting more commercially viable; it was the subject of a paper published in July in the journal Computers and Electronics in Agriculture.
The lead author was Zixuan He, who completed the work and earned his PhD at WSU’s Biological Systems Engineering Department before taking a position as a post-doctoral researcher at Aarhus University in Denmark. Co-authors included Manoj Karkee, a former WSU professor studying agricultural automation engineering who recently took a position at Cornell University and retains an adjunct faculty appointment with BSE; and Qin Zhang, professor emeritus and former director of WSU’s Center for Precision & Automated Agricultural Systems in Prosser.
The $20 billion strawberry market is projected to grow by 6% a year over the next decade, but labor shortages beleaguer the industry, driving up costs and potentially limiting harvests.
University and private researchers have pursued robotic harvesting technology for years, but the efforts to make them commercially workable have so far fallen short. Among the problems: many of the berries on strawberry plants are hidden under leaves, which makes it hard for robotic systems to identify and pick the fruit.
“Novel approaches like these are essential to improve the fruit accessibility and picking efficiency, and thus enhance the practical applicability of harvesting robots,” Karkee said.
Source : wsu.edu