The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions.
Degree: PhD, Mechanical Engineering, 2021, Virginia Tech
Bats are well-known for their intricate biosonar system that allow the animals to navigate even the most complex natural environments. While the mechanism behind most of these abilities remains unknown, an interesting observation is that some bat species produce fast movements of their ears when actively exploring their surroundings. By moving their pinna, the bats create a time-variant reception characteristic and very little research has been directed at exploring the potential benefits of such behavior so far. One hypothesis is that the speed of the pinna motions modulates the received biosonar echoes with Doppler-shift patterns that could convey sensory information that is useful for navigation. This dissertation intends to explore this hypothetical dynamic sensing mechanism by building a soft-robotic biomimetic receiver to replicate the dynamics of the bat pinna. The experiments with this biomimetic pinna robot demonstrate that the non-rigid ear motions produce Doppler signatures that contain information about the direction of a sound source. However, these patterns are difficult to interpret because of their complexity. By combining the soft-robotic pinna with a convolutional neural network for processing the Doppler signatures in the time-frequency domain, I have been able to accurately estimate the source direction with an error margin of less than one degree. This working system, composed of a soft-robotic biomimetic ear integrated with a deep neural net, demonstrates that the use of Doppler signatures as a source of sensory information is a viable hypothesis for explaining the sensory skills of bats.
Advisors/Committee Members: Mueller, Rolf (committeechair), Socha, John (committee member), Leonessa, Alexander (committee member), Abaid, Nicole Teresa (committee member), Roan, Michael J. (committee member).
Subjects/Keywords: Bats; Biosonar; Pinna Motions; Doppler Shifts; Direction finding; Biomimetics; Deep Learning
to Zotero / EndNote / Reference
APA (6th Edition):
Yin, X. (2021). The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions. (Doctoral Dissertation). Virginia Tech. Retrieved from http://hdl.handle.net/10919/101965
Chicago Manual of Style (16th Edition):
Yin, Xiaoyan. “The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions.” 2021. Doctoral Dissertation, Virginia Tech. Accessed February 26, 2021.
MLA Handbook (7th Edition):
Yin, Xiaoyan. “The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions.” 2021. Web. 26 Feb 2021.
Yin X. The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions. [Internet] [Doctoral dissertation]. Virginia Tech; 2021. [cited 2021 Feb 26].
Available from: http://hdl.handle.net/10919/101965.
Council of Science Editors:
Yin X. The Role of Actively Created Doppler shifts in Bats Behavioral Experiments and Biomimetic Reproductions. [Doctoral Dissertation]. Virginia Tech; 2021. Available from: http://hdl.handle.net/10919/101965