Fruit growers in Washington and elsewhere are struggling to find enough workers for harvesting and pruning. Washington state leads the nation in apple and sweet cherry production, which in 2023 contributed more than $2 billion to the US gross domestic product. An aging local population and a drop in migrant farm workers have made it difficult to hire the hundreds of seasonal workers farms need.
To address this, researchers at Washington State University developed a low-cost inflatable robotic arm to pick apples and perform other orchard chores. The arm is made of a soft, air-filled fabric and is stronger than the inflatable tube men used in outdoor advertising. It is two feet long, weighs less than 50 pounds with its metal base, and the materials cost about $5,500. The device can detect an apple, then extend and retract to pick fruit in about 25 seconds.
The design is safe for use near people and is unlikely to damage branches or fruit, so it suits modern orchards where branches run linearly or on a V-trellis. Compared with human pickers—who average an apple every three seconds—the inflatable arm is slower. Researchers are improving mechanical parts and the rudimentary detection system that now limits picking speed. They are also working to add more functions and to commercialize the platform with support from WSU's Office of Innovation and Entrepreneurship. The project received funding from the National Science Foundation, the USDA National Institute of Food and Agriculture, and the Washington Tree Fruit Research Commission, and it was tested at Allan Brothers Fruit in Prosser, Washington.
- Collaborations: Prosser Research Extension Center and Cornell University
- Testing site: Allan Brothers Fruit, Prosser
- Support from WSU innovation office and funders
Difficult words
- harvest — gather crops when they are ripeharvesting
- prune — cut parts of plants to control growthpruning
- seasonal — happening only at certain times each year
- migrant — a worker who moves for temporary jobs
- inflatable — filled with air and able to expand
- orchard — land where fruit trees are grown
- commercialize — develop and sell a product to market
- rudimentary — basic and not fully developed or advanced
Tip: hover, focus or tap highlighted words in the article to see quick definitions while you read or listen.
Discussion questions
- What advantages and disadvantages do you see for using the inflatable arm in orchards?
- How could farms combine this robotic arm with human workers during harvest?
- Do you think the device's cost and speed make it practical for small farms? Why or why not?
Related articles
Crop losses threaten food security across Africa
Researchers say climate shocks, pests and diseases are increasing crop losses across Africa. Erratic rainfall, flooding and biological threats reduce yields, lower incomes and affect national food supplies and global commodity markets.
