Harvard researchers have made a device that mimics complex birdsongs.
The device uses air blown through a stretched rubber tube to recreate birdsongs found in nature, including those of Bengalese and Zebra finches.
The research suggests that birds may have taken advantage of the physical properties of a soft material in a specialized organ to produce and control birdsong.
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Harvard researchers have made a device that mimics complex birdsongs. The device uses air blown through a stretched rubber tube to recreate birdsongs found in nature, including those of Bengalese and Zebra finches. Pictured is a zebra-finch
The study, published in the Journal of The Royal Society Interface, found that birdsong is the product of the controlled generation of sound.
Specifically, birdsong is generated by ‘controllable instability’ in the structure of a specialized organ used to create song, known as a syrinx.
To learn more about how birds actually generate their songs, researchers made a ‘biomimetic’ structure designed to mimic the syrinx organ.
This structure consisted of a stretched rubber tube through which air was blown, while being squeezed in certain locations with a linear actuator – a machine component that creates motion in a straight line.
By maintaining a large tension on the rubber tube and small dynamic variations in the localized squeezing, the researchers were able to control transitions in the song.
They controlled transition between three birdsong states: a quiescent (inactive) state, a periodic state and a solitary wave state.
The researchers used this method to mimic a range of birdsongs, via a either slow or fast manipulation of the syrinx, regulated by a simple controller.
This video shows localized depression being created at the location of the linear probe that pushes down on the rubber tube, designed to mimic a bird’s syrinx organ. This leads to a propagating pulse, followed by a short rest period and then the cycle repeats
In a video of the structure, one can see a wave as it moves through the tube.
The structure was imaged by placing a mirror to show the mouth of the tube, and following a refractory period, the process repeats itself.
‘Our study adds to the growing realization that physical instabilities with rich nonlinear dynamics, when coupled to relatively simple control mechanisms, may provide a mechanism for birds to begin to create complex behavior by taking advantage of their physical, material nature,’ said Dr Lakshminarayanan Mahadevan, a co-author of the study and a Professor at Harvard’s John A.Paulson School of Engineering and Applied Sciences.
Birdsong is generated by ‘controllable instability’ in the structure of a specialized organ used to create song, known as a syrinx. Researchers made a device to mimic a syrinx, using air blown through a stretched rubber tube to recreate birdsongs, including those of Bengalese finch (pictured)