Engineering expertise has been applied to improve the quality and efficiency of the automated harvesting of soybeans, thanks to a collaboration between engineers from Kyoto University and the University of Illinois.
Speed is important when a field of soybeans is ready to harvest. Despite the speed of modern harvesting mechanisms, quality control is still an issue. Soybeans that are whole, un-split and without stray husk material are the desired end product, but harvesting can be slowed down when the combine operator has to climb out of the cab to manually check for quality.
This is because when the threshing speed is too high, the soybeans can split or break as they are harvested. Whole beans are considered higher quality, and bring with them a higher price. Thus, operators currently have to periodically pause the threshing and manually check the tank in order to evaluate the quality and make adjustments.
The team of engineers aimed to develop a machine that can automate the process, evaluating bean quality on the fly, so harvesting can go on uninterrupted.
“The main objective was to develop an efficient, compact, on-board quality-monitoring system to evaluate soybeans as they are harvested, providing the combine operator with real-time grain quality information,” says Md Abdul Momin, lead researcher on the project.
“With this machine, operators can look at a screen and make adjustments as they go, without stopping.”
The system includes a high-speed camera, and is mounted inside the tank of the harvester. The camera takes images of the beans as they pass by, while a computer program analyses them in real time. The solution utilises a combination of both front and back lighting, allowing the camera to see the complete shape of the beans, so it is possible to identify beans that are split.
Momin tested the system first in the laboratory and then in field conditions. According to him, an off-the-shelf web camera would be sufficient for use in the processing industry with the system, but mounting it inside the combine is much more challenging, due to the speed of the soybeans. As such, a Japanese company is currently working to develop a higher speed camera to be used with the system.
According to Momin, soybean growers in Japan are eager to use the new technology, because the ability to evaluate beans during harvest will not just improve efficiency, but also improve the process by doing much of the sorting and cleaning of the soybeans before they reach the processing plant.
[Soybeans at harvest courtesy. Photo: United Soybean Board (US)]