wear might result in different intensities of the re-
flected laser beams.
• people could wear badges sending out for instance
infrared or ultrasound signals which can be re-
ceived by specific sensors to identify the tracked
people (Schulz et al., 2003).
• usually people wear clothing with different colours.
This information could be exploited for the identifi-
cation of the people using a camera network as has
been proposed in (Schumitch et al., 2006).
Since, up to our knowledge, our method is the first
to be able to track several interacting objects without
loss of track, it might be challenging to combine our
approach with one of these attempts.
So far, we only used a non moving observer. In
principle it is possible to extend the method to be suit-
able for moving observers. This is part of the ongoing
research and will be presented in following publica-
tions.
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