An overvhead view shows how the robotic system fits within the diameter of a 24-stall herringbone rotary.
For producers with large herds, the dream of robotic attachers on rotary parlors is one step closer to reality.
DeLaval has introduced its prototype robotic rotary, a 24-stall herringbone configuration that can milk up to 800 cows 2X or 540 cows 3X. That capacity comes with a Cadillac version of the automatic milking rotary: the AMR.
“Dairy farmers have been asking for an automatic milking rotary for a long time. We developed the AMR with three key customer benefits in mind: profitability, farm management and flexibility,” says Andrew Turner, DeLaval vice president of capital goods.
Since the AMR is still in development and must be tested commercially this year, the units are not yet for sale, nor have prices been determined. DeLaval officials will only say that the units will be sold at an economically attractive price. Commercial robotic rotaries should be available in 2012, Turner says.
The local labor supply will determine whether dairy producers choose robotic milking over conventional systems. “Not the price of labor but the quality of the work determines demand for robots,” asserts Joakim Rosengren, president and CEO of DeLaval.
“Whether in Europe, Russia, Australia, South America or North America, if there are no good milkers available, robots will take over the job,” he says.
In its current stage of development, there are two versions of the AMR, each with 24 stalls. The basic version has one robot for cleaning and prepping teats, one robot to attach the milker units and one robot for postmilking teat spraying. The higher-capacity version has two robots for prepping teats, two for attaching units and one for post-milking spraying.
With the basic version, one robot prepares all four teats while another robot attaches cups to all four teats. In the high-volume version, four robots work on four cows at the same time. Each robot prepares two teats and attaches cups to two teats. The rotary then moves forward, and the next robot preps and attaches the remaining teats. A fifth robot is used to disinfect all of the cow’s teats after milking is completed.
The basic version has a capacity of 50 cows per hour. This forces a larger herd to milk in groups, rather than allowing the cows to come to the parlor voluntarily.
Milking in groups would allow the high-capacity parlor to milk up to 800 cows 2X. Allowing cows to come voluntarily to the high-capacity AMR would lower the number of cows milked 2X to 700.
The cows walk onto the carousel as onto a traditional rotary. Each cow is identified through electronic ID, but if she is coming voluntarily rather than in a group, she can only enter the stall after a certain time has passed since the previous milking.
When a cow enters the stall, the parlor stops at the first robot position, where individual teats are washed and dried. The platform then moves forward to the next robot, where the individual teat cups are attached. As milking is completed, the cups are automatically removed and the teats are sprayed with teat dip as the cows leave the parlor.
The AMR monitors milk yield, somatic cell count and milk color (blood) for each quarter of each cow. However, unlike the stationary voluntary milk systems where cows enter individual stalls, the current AMR versions do not separate milk of inferior quality. The dairy producer must therefore be very keen on the health of the cows and milk questionable or treated cows separately.
“Not offering milk separation on the AMR is a choice we have made based on cost and efficiency,” says Jonas Hallman, DeLaval’s director of automatic milking systems. Technically, such a system is possible. “However, using the AMR for only a few cows would make it rather expensive, while it would limit capacity,” he says.
In addition, concentrate feeding during milking will not be an option with the current class of robotic rotaries. The reason: “Cows that eat move more,” Hallman says. As a result, teat preparation and teat cup attachment is that much more difficult and slower.
The first prototype robotic rotary parlor was built at DeLaval’s Hamra Farm, a test facility in Sweden, in 2008. A second prototype was installed at the FutureDairy research and test farm in New South Wales, Australia.
The main problem when developing the system was how to clean teats and attach units on a moving cow on a moving platform with a moving robot.
The solution is a sensor that registers the location of the cow. The sensor guides the robot arm toward the teat, helped by coordinates that are stored in the memory of the system. The exact position of the teat is then identified by a camera and laser. The system is suitable for all sizes of cows, DeLaval says.
One innovation of the robotic rotaries is that each robotic arm is equipped with two magnetic clips that each holds a teat cup. As a result, connecting two cups requires only one arm movement.
At the beginning of the project, DeLaval engineers toyed with the idea of working with an external parallel rotary and attaching the teat cups through the back legs of the cows. But this approach did not work very well.
As an alternative, an internal herringbone configuration was developed. The herringbone makes it possible to approach the cow from the side, like robots in conventional, single-box systems.
The downside is that the AMRs can’t be retrofitted onto existing rotary parlors that attach units between the two rear legs. But retrofits on herringbone parlors configured for inside-the-diameter attachment might be possible, depending on the dimensions of the parlor and the stalls. Due to the weight of the robotic attachers, a heavier suspension and rollers will likely be required.
However, DeLaval officials foresee the day, perhaps within a decade, that robotic milkers could be used in straight-line, parallel parlors. They say such parlors would simply give producers another milking system option.
The new AMR system is a collaboration between DeLaval and the Australian FutureDairy project, which includes Dairy Australia, Industry & Investment NSW, the University of Sydney, Dairy NSW and the Dairy Research Foundation.
- January 2011