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Horseshoe bats (family Rhinolophidae) are a group of bats with a particularly sophisticated biosonar
system that allows them to navigate and pursue prey in dense and complex living areas. One
conspicuous feature of horseshoe bat biosonar is that the pulses are emitted nasally and diffracted by a
special baffle structure - the noseleaf - as the exit into the free field. Furthermore, the noseleaves can
change their shapes while diffracting the outgoing ultrasonic waves. The aim of this research project is
to determine the relationship between the deformation of the noseleaf during pulse emission and the
ultrasonic field through experiments. 3D models of horseshoe bat noseleaf were obtained by
tomographic imaging, reconstructed, and modified in the digital domain to meet the needs of additive
manufacturing prototypes for an experimental setup. A data acquisition and instrument control system
was developed and integrated with ultrasonic transducers to characterize the dynamic emission system
acoustically, actuators for displacing the lower and top portion of bat noseleaf, and pan-tilt unit for
orienting the noseleaf. A cone and tube waveguide was designed to match the loudspeaker to the
nostrils of bat noseleaf. By using this system, it was possible to reproduce the dynamic effect of the
noseleaf and characterize it as a basis for inspired dynamic acoustic devices. Future research will
address the relationship between the deformations of the noseleaf and the acoustic field.
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