Summary
A very successful pattern recognition experiment has been carried out with a dolphin identifying a solid sphere versus a hollow one. Results suggest that the dolphin utilized a time difference cue to distinguish between the two spheres. A theoretical evaluation of the physics of the targets, involving a model of the dolphin sonar, has been carried out. The ensonifying signal follows the model of an elementary signal as proposed by Gabor, i.e. a harmonic signal with a Gaussian envelope. The numerical values of the 3 needed parameters are estimated from the sonar recordings of the live experiment. The target modelling of the sphere is done with the quantities inner-to-outer diameter, density of the metal, and longitudinal and transversal wave velocity. A good match between the computational model and the actual experiment shows up.
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© 1988 Plenum Press, New York
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Lanen, T.A.W.M., Kamminga, C. (1988). Echoes from Solid and Hollow Metallic Spheres. In: Nachtigall, P.E., Moore, P.W.B. (eds) Animal Sonar. NATO ASI Science, vol 156. Springer, Boston, MA. https://doi.org/10.1007/978-1-4684-7493-0_87
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DOI: https://doi.org/10.1007/978-1-4684-7493-0_87
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