novel approaches to expression and detection of oestrus in dairy cows

Initial tests were carried out to investigate signal
strength and accuracy of position within the dairy
barn. The dairy farm is an environment with many
obstructions; steel girders, heavy machinery and
with lots of structural metal work. Furthermore the
cows are milked by robots whereby the cows enter
into the machine one at a time to be milked, which
is an enclosed area, and may cause obstruction to
the signal. Within the cow barn in each cow
location (one location houses approximately 40
cows each, all milking via 1 robot, with 4 locations
in total) there are cubicles for individual cows to
stand or lie down in, in comfort on shavings, which
are raised by 20cm. Cubicles line the centre of the
barn, some may be in ideal positions for good
signal quality and some may be in poor positions
where there is more obstruction. Opposite the
cubicles is the feed passage where cows stand with
Figure 4.2 UWB unit
that can be configured
as either base unit,
mobile unit or control
unit
their heads facing outwards and are fed. This is also an open area where
cows stand and mainly interact with one another; therefore the accuracy of
UWB in these areas must be determined.
When handling cows they are taken to the management/AI stalls, which is
an area behind the robots, outside of the main cow location, where up to
10 cows can be separated for handling in a controlled environment. The
management/ AI stalls are behind the locations where the cows live and
was therefore outside of the BU network. Positioning accuracy needs to be
tested in all of the potential areas where cattle may interact, particularly
areas which may relay a poor signal due to obstruction by structural
components of the farm, to determine whether UWB is suitable for use at
the dairy farm.
Preliminary static and kinematic tests in the cow barn using small and large
networks of BUs to monitor MU position demonstrated accuracy in all 3
dimensions: X and Y horizontal positioning and Z vertical positioning. Static
tests are useful to determine the overall accuracy of position recorded by
UWB in reference to the BU network when the MU is stationary for a period
of time. Kinematic accuracy is testing the accuracy of the MU when the unit
is mobile and thus changing position. To test the horizontal positioning
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