Dynamic periphery in a biomimetic sonar system introduces time-variant signatures into targets echoes

• Published in: The Journal of the Acoustical Society of America 2016-10, Vol.140 (4), p.2974-2974
• Main Authors: Sutlive, Joseph, Caspers, Philip, Müller, Rolf
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.4969202

Bats have developed unique and refined systems of echolocation throughout the course of their evolutionary history, giving them the ability to navigate and hunt in extremely cluttered environments. While the mechanisms behind many of these abilities remain unknown, it has been observed that the most effective biosonar systems in bats use a variety of dynamic sensing mechanisms. One conspicuous manifestation of this dynamics can be seen in changes to the shapes of the baffle that diffract the emitted biosonar pulses (noseleaves) and the returning echoes (outer ears). Using numerical predictions as well as measurements with biomimetic hardware, our own prior work has established that the dynamics in these baffles can create time-variant emitter and receiver characteristics. However, it has yet to be demonstrated that these time-variant device characteristics have a substantial impact on the received echoes. To address this question, a biomimetic sonar head with dynamic emission and reception baffles was used to ensonify a range of different targets that included simple geometrical shapes (e.g., sphere, cylinder, and cube) as well as natural targets (foliage). The biomimetic dynamics of the sonar head resulted in time-variant signature in the received echoes that could provide a substrate for encoding additional sensory information.