Autor: |
Emma Suriñach, Jordi Llosa, I. Vilajosana, Marius Schaefer, Xavier Vilajosana |
Rok vydání: |
2011 |
Předmět: |
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Zdroj: |
Cold Regions Science and Technology. 65:242-250 |
ISSN: |
0165-232X |
DOI: |
10.1016/j.coldregions.2010.09.011 |
Popis: |
Specially designed wireless accelerometers units were used in a series of experi- ments at the snow chute operated by the SLF at Weissfluhjoch (Switzerland) during two consecutive winters. The purpose of the experiment was to evaluate the best design and the performance of these innovative instruments to provide information on the internal dynamics of flowing snow. The wireless accelerometers were placed in the snow chute starting zone prior to the experiments and traveled within the flow when the avalanche was released. The characteristics of the units (size and density) allow them to evolve like active particle tracers. Acceleration readings obtained at 85 Hz for the different experiments where analyzed. The analysis methods used include Empirical Mode De- composition, Kalman Filtering techniques and inertial navigation signal processing techniques. The developed methodologies were used to obtain reliable speed and position values from the single 2D acceleration measurements. The obtained results were compared to independent measurements of speed and position of the sensors. The results show to be in agreement with that obtained from inde- pendent speed measurements from optical sensors and Video Images and open a new perspective for future avalanche research. The extracted information could provide valuable data related to internal dynamics of the avalanche. Small-scale chutes are the ideal scenario to test these new technologies. Moreover, we consider this sites essential to develop and test new instrumentation (to be deployed), in the future, in full-scale experiments. In addition, the experiments performed show for the first time the potential of the wireless technologies and wireless sensors to study snow avalanches. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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