novel approaches to expression and detection of oestrus in dairy cows

a
b
c
Figure 4.12 Static tests to determine
height accuracy of BU geometry in areas
of good and poor signal quality according
to HVDOP (Figure 4.9). a) static test in
area of good signal quality, b) static test
in area of poor signal quality in far corners
of the location and c) static test in robotic
milker, an area of suspected high
multipath and poor signal quality as
identified by HVDOP
These tests demonstrated that in areas of good quality UWB signal
coverage, according to the HVDOP, that height can be determined to
centimetre accuracy. Importantly this was still achievable in areas of poor
signal quality with the average height being determined with only 10cm
error and in the robotic milker it is surprising to see that accuracy is equal
to that in areas of ‘good positioning’ as shown in Figure 4.9. The height is
20cm higher in the robotic milker due to a step up, which is noticeable by
the different static heights in Figure 4.12; however it is encouraging that
this elevation in height could even be detected. Progression onto kinematic
tests to determine height accuracy followed this series of static tests using
the same methods; MU attached to a pole and someone walking around,
altering the height manually. Results are presented in Figure 4.13, showing
that general movement within the network can be monitored as the MU
gradually changes height. This finding is consolidated with the knowledge
that height changes can still be determined in areas of poor coverage, even
when occurring in quick succession so as to simulate the effect of a
94