![](bg4.png)
At the tube trial we were looking for the
maximum frequency of any requested address and it
results on 1.88 MHz for the 64x64 retina and 8.33
MHz for the 128x128 retina.
For the 64x64 pixel retina, if we join together the
10 ms obtained at the Lathe scenario between two
consecutive events of the same pixel, that could be
called frame time, and t2+t4+t5+t6 obtained on the
tubes scenario between any two consecutive events,
a maximum to 18867 addresses could be placed on
the AER bus. If we had considered an address space
of 4096 pixel, it would have confirmed the fact of no
lost events.
For the 128x128 pixel retina, it is possible to
pick up a similar case. If we considered the peak of
1.3KHz (769.23 us) like the top spike frequency for
a pixel and join it together with the sum of t2, t4, t5
and t6 obtained on the tubes scenario, it is possible
to place 6410 addresses within the frame time. If we
had considered an address space of 16384 pixel, it
noticed that lost events could appear with the peak
frequency selected, but this situation is not actually
very real because we have considered the peaks of
frequency spikes. If we have taken a frequency of
500 Hz, which is the saturation level for our test, no
lost events appears.
5 CONCLUSIONS
We have presented a study of two different
retinomorphic systems to use them in a visual
surveillance at any industrial environment. We have
checked the upper limit of the first system with a
Lathe, approximately 6000 rpm and no limits for the
second system at usual manufacturing machinery. It
has been tested at an ultra fast CNC Machine up to
10000rpm with an excellent result. Also, the results
reveal that in the worst condition of luminosity
change for our retinas there will be no lost of events
for the first one and at the second one could be some
very improbable lost event. Therefore, these AER
retinas can be used for a visual surveillance system
at any high speed industrial manufacturing
machinery.
ACKNOWLEDGEMENTS
This work was supported by the Spanish grant
VULCANO (TEC2009-10639-C04-02).
Also thanks to group Engineering Materials and
Manufacturing Technologies, TEP-027.
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