Characterization of harbor seal whisker

Abstract

Many studies conducted so far focused on harbor seal whiskers’ ability to discriminate shapes, sizes, and to sense the hydrodynamic trails. However, very few researches have been done on the material properties of these whiskers. Hence, this project focused on characterizing the resonant properties of harbor seal whiskers. Experiments were conducted on three different lengths; short, medium and long whiskers at different angular orientations. In addition, a theoretical model based on elliptical conical beam, was developed to study the behaviour of the whiskers. To validate this model, the experimentally obtained resonant frequencies were compared with the results obtained from a theoretical model of the harbor seal whiskers. Experimental results showed that different orientations had strong effect on the vibration amplitudes of the whiskers but not on resonant frequencies. Furthermore, it was found that an increase in the mode number caused a corollary decrease in the vibration amplitude. The findings also showed that resonant frequencies decreased with increasing length. However, the decrease was insignificant. The comparison between the theoretical and experimental values showed that there was a disagreement between both values, which was believed to have been caused by non-ideal conditions in the experiments and the reductive assumptions made for the theoretical model. Hence, a scaling factor was introduced. This exemplified that the proposed model did not accurately represent the whisker and further developments with better assumptions are required.