Researchers at the University of Cambridge have developed a robot that harvests lettuce. Although the prototype named "Vegebot" is nowhere near as fast or efficient as a human worker, it can be considered an achievement in the agriculture robotics field, as described in a study published in the latest issue of The Journal of Field Robotics journal.
Crops such as potatoes and wheat have been harvested mechanically at scale for decades, but many other crops such as iceberg lettuce have to date resisted automation, for two reasons: they can be easily damaged and grow relatively flat to the ground, presenting a challenge for robotic harvesters. Yet, these two problems have been addressed with the new robot.
At the moment, harvesting is the only part of the lettuce life cycle that is done manually, and it's very physically demanding. The researchers also hope Vegebot will contribute to a reduction in costs.
The robot first identifies the 'target' crop within its field of vision, then determines whether particular lettuce is healthy and ready to be harvested, and finally cuts the lettuce from the rest of the plant without crushing it so that it is 'supermarket ready'.
The Vegebot has two main components: a computer vision system and a cutting system. The overhead camera on the Vegebot takes an image of the lettuce field and first identifies all the lettuces in the image, and then for each lettuce, classifies whether it should be harvested or not. Lettuce might be rejected because it's not yet mature, or it might have a disease that could spread to other lettuces in the harvest.
A second camera on the Vegebot is positioned near the cutting blade and helps ensure a smooth cut.
In an email he sent to Asharq Al-Awsat, co-author Josie Hughes admits that: "The robot is slower than human in lettuce harvesting. For a human, the entire process takes a couple of seconds, but it's a really challenging problem for a robot. However, reducing the dependency on humans may help shrink the expenditures, and that's why the new robot is considered economically efficient. "
"We've still got to speed our Vegebot up; however, we plan to market the prototype, which is still being tested before deploying it in fields."
