Self milking cows

This is actually the second time I've heard this story, but I lost the first one.

A dairy farm has set up a booth that a cow can walk into, get milked, and then released. Cows do want to be milked -- an un-milked cow's udders are swollen and sore, and this system allows the cow to be milked when the cow wants it, not just when the farmer is available. The first time I heard about this, it was a different farm, with slightly different technical specifications, and it was not selling the system to other farms.

The system in the article uses an embedded computer with Linux as an operating system. The cow walks into the booth, and the booth recognizses, by the change in weight, that a cow has entered. A robotic probe finds the udders, cleans them, and attaches the milking device. The device milks the cow until no more milk flows forth, and then the door opens and the cow is gently pushed out. The booth cleans itself after the cow is gone. The cows have the entire system down pat within a few days, and milk themselves about 6 - 12 times per day. A farmer tends to milk a cow 1 - 4 times per day.

The first time I heard of this kind of thing, long ago on Slashdot, the computer was based off of Berkley's BSD, a Unix system that inspired Linux, the farm had 4 booths, and that farm was not going to sell the system to other farms. This article does not say how many booths it has, but mentions that the dairy itself is 122 years old -- likely it has thousands of cows.