One of the biggest commercial opportunities for robotics is agriculture, which I find endlessly fascinating (probably because I know nothing about farming!). This isn't exactly drone-related (although lots of farmers are using drones for everything from multispectral imaging to crop-spraying), but Forbes has a good roundup of some recent developments:

A new project that’s part of the European Union Seventh Framework Program (FP7) cRops (Clever Robots for Crops) is focusing on creating robots to harvest high value crops.

The cRops robotic platform will be capable of site-specific spraying (targeted spraying only on foliage and selected targets) and selective harvesting of fruit. The robots will be able to detect the fruit, sense its ripeness, then move to grasp and softly detach only the ripe fruit. Another objective of cRops is to develop techniques for reliable detection and classification of obstacles and other objects to enable successful autonomous navigation and operation in plantations and forests.

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Harvest Automation, based in Boston, MA, raised $7.8 million in a series B funding round in November 2011. Harvest is focusing on agricultural robotics and focusing on greenhouse and nursery automation. They want to resolve acute manual labor problems across multiple industries but are starting with agriculture. The Harvest Automation robot costs around $25 to $50k and because the manipulation requirements of the robots are lower in this sector, the company focus on creating a viable business, reducing costs and higher yields, rather than worrying about how to incorporate expensive robot arms into their operations.