A vegetable-picking robot could be the solution for tackling labour shortages in the agricultural supply chain, according to academics.
The University of Cambridge has trialled its Vegebot robot on iceberg lettuce, using machine learning to identify and harvest the crop.
The prototype demonstrates how the use of robotics in agriculture might be expanded and could help with labour shortages and reduction of food waste, according to the university.
Previously, using robots to harvest fragile crops such as lettuce has been “challenging”, as they are easily damaged and grow flat to the ground. However, researchers were able to create adjustable pressure in the robot’s gripping arm, so that it holds the vegetable but doesn't crush it. A special cutting system, meanwhile, cuts it to “supermarket-ready” standards.
Dr Fumiya Iida, head of the research team, said: “We wanted to develop approaches that weren’t necessarily specific to iceberg lettuce so that they can be used for other types of above-ground crops.”
The Vegebot uses a computer vision system to identify the crop and assess whether it is free of disease and ready for harvest, and a cutting system with a second camera near the blade. The robot began testing in the laboratory and was later trialled under a variety of weather conditions with help from G’s Growers Ltd, a Cambridge fruit and vegetable co-operative.
A recent International Labour Organization report on how rising temperatures will affect global production determined that the agricultural sector could lose 60% of working hours to heat stress in 2030, and that using machines instead of humans could be a possible solution.
Josie Hughes, a researcher on the project, said that data on lettuce is being collected, “which could be used to improve efficiency, such as which fields have the highest yields.”
The robot could also contribute to food waste reduction. Unripe fruit and vegetables are usually thrown away but the machine learning system has been programmed to pick only ripe crops or return when unripe crops have matured, according to the University of Cambridge.
Harvesting is the only manual part of the lettuce’s life cycle, said Julia Cai, a former undergraduate student who worked on the project, suggesting that this robot could enable full automation for the supply chain.
The Cambridge research team is part of the world's first Centre for Doctoral Training in Agri-Food Robotics, in collaboration with the University of Lincoln and the University of East Anglia.
The results of the trials for the robotic harvesting system were published in The Journal of Field Robotics.