Gathering in the harvest

How can a robotic harvester gather one crop without damaging the other immature plants?

I was pleased to read Julian Vincent’s letter (20th June, 2012) regarding robotics in farming. It would be good if he could publish an article on the subject in Professional Engineering. I believe Harper Adams University College is currently involved in research and development in this field of Agricultural Engineering.

I would be interested to know if the figure of “5 times to 10 times more productive” relates to “natural” ecosystems. Is he referring to a fully “Omni-culture” or some intermediate system such as fruit trees acting as shade for delicate irrigated crops and separated by cereal strips?

If he is writing about a perennial multi-crop random planting system, I have real problems with robotic harvesting systems. Can he explain how a robotic harvester can gather one crop without damaging the rest of the as yet immature plants? Using ‘back of an envelope’ calculation I estimate that such a machine might be some 1 metre wide and gather 100-150kg per foray into the field. To match a “mono-culture” harvester one might need 20-40 units moving randomly through the crop searching for specific ripe tomatoes for example. These activities would destroy the bulk of any of the, as yet, unharvested immature material.

Geoffrey Wakeham, Shropshire

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