Teat-seeking robot to help cows milk themselves
Soft-touch technology could increase yields while farmers lie in.
nature.com
12 March 2003
Tom Clarke
Dairy farmers of the future may sleep safe in the knowledge that an udder-friendly robot is doing the day's milking.
"The idea is to replace farmers' hands and allow cows to milk themselves whenever they fancy," says engineer Bruce Davies at Heriot-Watt University in Edinburgh, UK.
Davies' company IceRobotics has just received a £98,000 (US$157,000) grant from Britain's National Endowment for Science, Technology and the Arts to develop its rubbery manipulator - the 'continuum activator' - into a flexible, teat-seeking robotic arm.
Frequent milking yields more than conventional morning and evening trips to the dairy. And cows produce more when they choose their own milking schedule - often at the times when calves naturally like to feed, between 11 pm and 3 am.
Milking is backbreaking work: in America's dairy state of Wisconsin, for example, it consumes 50 million worker hours each year. "Automated milking is potentially big business," says Albert Meijering of the Research Institute for Animal Husbandry in Lelystad, the Netherlands.
The continuum actuator was inspired, says Davies, by an elephant's trunk. It is made of a rubbery polymer, and fluid is pumped at varying pressures down three central chambers to make it extend, contract or bend at any angle. Finger-like manipulators at the arm's end add dexterity - stiff-armed robots "can have trouble catching all the angles teats can take", says Davies.
Using an infrared camera, the arm will zero in on one of a cow's warm teats and use it to locate the others. It will then place conventional suction-powered milking cups over each of them.
Rigid approach
Since the late 1990s, some 1,800 farms in northern Europe and North America have introduced automated milking machines. These use a rigid robotic arm, similar to those in car-manufacturing plants, to attach milking cups to between two and ten cows waiting in stalls.
Davies says that the strength of his device is its softness. "I build robots that can shake hands with people without the risk of slicing their head off," he says.
But its not just robotics that's preventing every dairy farm from going automatic, notes Meijering - it's also the cows.
Some animals happily visit existing robotic milkers day and night. But in every herd there are a stubborn few that spurn automation, prefering the human touch. "Several cows have to be fetched a couple of times a day," says Meijering, which makes the cost of robotic milking of large herds difficult to justify for the time being.
© Nature News Service / Macmillan Magazines Ltd 2003 |
