Hyperspectral machine to automated cauliflower harvesting
Scientists at Fraunhofer Institute for Factory Operation and Automation IFF are developing a prototype machine for harvesting cauliflower based on hyperspectral imaging.
The researchers say the system, called VitaPanther, will be able to harvest cauliflower heads significantly faster than human pickers. It could also work at night.
Hyperspectral imaging is used to determine the ripeness of cauliflowers by assessing the biochemical composition of the leaves. Cauliflower is a difficult crop to harvest because the white heads are hidden beneath leaves; pickers have to pull back the protective leaves to decide whether the cauliflower is ripe for harvesting. Hyperspectral cameras give an indication of ripeness by analysing the chemical composition of the leaves.
Martin Steig, farmer and CEO of Steig, and one of the future potential users of the harvester, commented: ‘Automation is essential for us farmers, because the minimum wage is making vegetable harvesting unfeasible. Harvesting is sustained by two components: the availability of a seasonal workforce and the pay. A shift in one of these components jeopardises the structure. The demand for technology is thus very great.’
The mathematical model that decodes the camera images to give a yes-no command is based on algorithms that originated with machine learning – the researchers use examples to teach the system. They show the camera different heads of cauliflower, which are simultaneously being inspected by a human expert. Following such a teaching phase, the system is able to decide autonomously which cauliflower should be harvested or not, even when the heads of cauliflower are unfamiliar.
Alongside researchers at Fraunhofer IFF, the system is being developed by colleagues at AI-Solution, together with five other partners: Gottfried Wilhelm Leibniz University Hannover, Steig, Beutelmann Gemüseanbau, König Sondermaschinenbau, and Inokon. A prototype of VitaPanther will be finished and tested in 2017.
While the researchers from the Fraunhofer IFF are attending to the sensor systems and data analysis, their colleagues from AI-Solution in Wolfsburg are working on the harvester unit that will be harvesting cauliflower heads in the future. They are building upon their asparagus harvester, Spargelpanther, for this. ‘We also intend to use this asparagus harvester for other vegetables – cauliflower and head and leaf lettuce. Then, other harvester modules for other vegetables could be added in the future,’ said Christian Bornstein, CEO of AI-Solution. ‘Our goal is to build a module that can be adapted to the existing unit.’
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