A strawberry harvest-aiding system with crop-transport co-robots: Design, development, and field evaluation
This addresses labor inefficiency in the fruit industry, specifically for crops like strawberries, though it is an incremental step toward automation.
The paper tackled the inefficiency of manual fruit harvesting by developing a co-robotic system that transports trays to reduce pickers' walking time, resulting in a 10% increase in harvesting efficiency and a 60% reduction in non-productive time during field tests.
Mechanizing the manual harvesting of fresh market fruits constitutes one of the biggest challenges to the sustainability of the fruit industry. During manual harvesting of some fresh-market crops like strawberries and table grapes, pickers spend significant amounts of time walking to carry full trays to a collection station at the edge of the field. A step toward increasing harvest automation for such crops is to deploy harvest-aid collaborative robots (co-bots) that transport the empty and full trays, thus increasing harvest efficiency by reducing pickers' non-productive walking times. This work presents the development of a co-robotic harvest-aid system and its evaluation during commercial strawberry harvesting. At the heart of the system lies a predictive stochastic scheduling algorithm that minimizes the expected non-picking time, thus maximizing the harvest efficiency. During the evaluation experiments, the co-robots improved the mean harvesting efficiency by around 10% and reduced the mean non-productive time by 60%, when the robot-to-picker ratio was 1:3. The concepts developed in this work can be applied to robotic harvest-aids for other manually harvested crops that involve walking for crop transportation.