Agency: USDA NIFA
Karkee, M.*; Whiting, M.; Zhang, Q.
Currently, apple harvesting is performed manually around the word, which requires a large, semi-skilled workforce for a short time. To reduce harvest costs and dependence on labor, researchers have been seeking mechanical/robotic solutions for decades. Shake-and-catch technology is one of the ways, which has been successful in harvesting fruit for the processing market, but no commercial success has been achieved in harvesting fresh market apples because of fruit damage. In this project, we aim to develop a targeted shake-and-catch technology for fresh-market apple harvesting. Tests were carried out with various designs of shaking and catching mechanisms for a targeted shake-and-catch harvesting system. Multiple layers of cushioned catching surfaces were used. Fruit drop tests were used to identify potential sources of bruising and to identify catching surface materials that may reduce fruit bruising. To reduce impact force on fruit during harvesting, a new catching device was designed. A dynamic test was also conducted to investigate the energy transmission to different locations in the limbs with different type of shaking mechanisms. An optimized mechanism was then evaluated for targeted shake-and-catch harvesting of various apple cultivars. It was found that the fruit removal efficiency and quality were depended on the cultivars. For the varieties tested, fruit removal efficiency varied from 70% to 90% with US Extra Fancy fruit (bruise diameter less than 12.7 mm) varying from 65% to 90%. It was found that ‘Fuji’, ‘Jazz’, and ‘Pink Lady’ varieties performed better in terms of fruit removal efficiency and fruit quality, showing the potential for targeted shake-and-catch harvesting of fresh market apples for certain varieties.