EVEN in the developed world farming can be a labour-intensive business, relying on lots of migrant workers. Cereal agriculture is heavily mechanised, with one combine harvester taking over from hundreds of labourers, but other tasks have proven difficult to automate. That is changing.



Meet Harvey, otherwise known as Harvest Vehicle HV-100. This is the first agricultural robot from Harvest Automation, a firm based in Massachusetts. It will work in horticulture where the traditional sources of cheap labour are becoming scarcer, in part because of changing demographics and immigration laws.



Harvey will begin moving potted trees and shrubs in plant nurseries. These are bunched closely together in winter, spaced wider in summer and rearranged as they get bigger. There may be hundreds of thousands of pots at one nursery and, says Greg Timbol, in charge of business development at Harvest Technologies, each pot typically needs to be moved at least five times, at a labour cost of about two cents per move. Hence the opening for a robot.



The robot is a battery-powered machine weighing 40kg with grippers to move any pots of up to about 10kg. It is designed to work safely alongside humans, unlike industrial robots which have to be fenced off to prevent accidents. And it can beaver away in all weathers, day or night.

Harvey has a variety of sensors to avoid obstacles and people and navigate with high precision. The developers have made the interface as simple to use as possible; the operator instructs Harvey by setting five parameters and laying down a single line of yellow tape as a reference marker. Multiple Harveys can also work together co-operatively as a team without obstructing each other.



Prototypes were successfully tested earlier this year. Human workers were happy to leave the arduous task of moving pots to the patient little machines. The first production versions will be delivered in September. They cost about $30,000 but, adds Mr Timbol, should pay for themselves in 12-25 months.



Upgrades are likely to follow, so the robots can spray, trim or prune, grade and move stock. This might involve novel ways of working; for example, the robot carrying trees would pass through an automated trimmer or sprayer. They may also start harvesting pumpkins and watermelons, using their sensors to determine which ones are ripe.



Other firms are looking at making robots for agriculture. The Vineland Research and Innovation Centre in Ontario has three robotic projects. One involves planting tulip bulbs and replanting seedlings, another will harvest, trim and package mushrooms and the third will package potted plants. All are based on conveyor belts and use commercial robots equipped with suction cups to handle small objects. Vision software developed by Anoven, also of Ontario, allows the robots to orient bulbs the right way and determine which mushrooms to pick.



Both Harvest Automation and Vineland have concentrated on robots working in structured environments, where they can achieve immediate gains. Tasks like fruit picking, with robots operating in a complex natural setting, are far more challenging and will require better sensors and more intelligence. But robots, like all workers, have to start somewhere.