Solc, T.: Analiza signalov sistema za merjenje gibanja prodnikov.
Univerza v Ljubljani, Fakulteta za elektrotehniko, 2004.


Abstract

We have applied standard time and frequency domain methods of signal
analysis to signals that have been recorded in controlled laboratory
environment using instrumented tracer for measuring dynamics of sediment
transport.

We have determined that it is not possible with the current version of the
instrument to calculate its path in the laboratory frame of reference from
the recorded signals alone. It is however possible to determine the
approximate mode and in some cases speed of movement (for example in the
case of rolling). During analysis we have also found some flaws in the
currently used accelerometers.

We have developed an effective and computationally unintensive algorithm
for automatic detection of impacts that is based on time domain analysis.
Using this algorithm we have analyzed the recorded impacts of the
instrumented tracer. We have determined two typical parameters for each
impact using statistical analysis and theoretical modeling. We have shown
that it is possible to determine the material of the impacted object from
these two parameters with a high degree of certainty.

Frequency domain analysis has shown that unwanted vibrations occurred during
the measurements and that the source of these vibrations was probably not
connected with the instrumented tracer. We have also found a method of
discriminating different signals. This method, combined with time domain based
methods, allows us to classify all recorded signals into groups based on
similarity of measurement conditions.