This thesis describes the development of a simple vibration measurement system in the price range of less than 50 euros. By reflecting a laser beam from a moving mirror (optical part) and detecting the position of its projection using a linear optical CCD sensor (digital part), we can measure vibrations with frequencies up to 100 Hz. The quality of the measurements was evaluated experimentally with artificially generated vibrations and by a longer-term setup in a real environment of a building with a large number of passing pedestrians. We found that the solution in its current form is suitable for recording seismic activity. However, further research is needed to evaluate the applicability of the system for more accurate measurements needed for earthquake prediction. We have also analyzed the applicability of the system for use in presence detection and found that it can successfully detect footsteps originating from the same room.
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