Research on Test Conditions of Sealed-Relay Remainders Based on High-Speed Video Technology - Intelligent Computing for Sustainable Energy and Environment - page 512

Table 4. y average results of experiments with varying frequency (m / s)

f (Hz)
H , R (mm)

20 30 40 50 60 70 80 90 100 110

40,1.5 0.929 0.772 1.227 0.630 0.465 0.401 0.727 0.279 0.227 0.128

40,1 0.897 2.925 1.173 0.595 0.681 0.398 0.353 0.430 0.332 0.105

20, 1.5 1.078 1.326 0.521 0.687 0.998 0.485 0.399 0.336 0.315 0.147

20, 1 1.002 1.357 0.496 0.607 0.603 0.456 0.368 0.316 0.296 0.129

The experimental results show that:

a) Frequency of the test conditions has a great influence on the test results. If other
conditions are fixed, the y average reduces obviously while the f increases, which verified
the theory in [9] and [10]. The reason is the acceleration time of remainders and test
objects gradually decreases with the increase of vibration frequency.
b) The remainder sometimes performs approximate periodic collision vibration in
the sealed cavity. The phenomenon of approximate periodic collision vibration has a
great influence on the test results, which may double the y average and improve the
success rate of detection effectively.
c) The phenomenon of approximate periodic collision vibration does not always
improve the y average ; it may make the y average less than the value of adjacent high-
frequency conditions with small probability.

2) Experiments of Varying Acceleration
Varying acceleration experiments were also performed. A 1.5mm diameter bearing
steel ball was selected to be a remainder; the size of transparent cavities are
40mm×40mm×70mm and 20mm × 20mm × 20mm respectively; the range of a m was
set between 2g and 10g and a was step changed by 1g each time. In order to minimize
the interference of approximate periodic collision vibration, f is fixed at 50Hz; and
likewise, 50 images are selected. The y average of the experiments with varying
acceleration are shown in Table 5.

Table 5. y average results of experiments with varying acceleration (m / s)

a (g)

H 2 3 4 6 7 9 10

5 8

(mm)

70 0.033 0.041 0.083 0.119 0.187 0.227 0.289 0.283 0.290

20 0.223 0.483 0.629 0.691 0.717 0.763 0.706 0.720

0.687

The above three experiments indicate that:

a) Acceleration peak value of the test conditions has a great influence on the test
results. If other conditions are fixed, the y average increases while a m increases. The
reason is that the acceleration time of remainders and test objects can obtain a higher
speed during the same accelerating time.