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Biomimetic and Live Medusae Reveal the Mechanistic Advantages of a Flexible Bell Margin

Colin, Sean P. and Costello, John H. and Dabiri, John O. and Villanueva, Alex and Blottman, John B. and Gemmell, Brad J. and Priya, Shashank (2012) Biomimetic and Live Medusae Reveal the Mechanistic Advantages of a Flexible Bell Margin. PLoS ONE, 7 (11). Art. No. e48909. ISSN 1932-6203. PMCID PMC3492145.

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Flexible bell margins are characteristic components of rowing medusan morphologies and are expected to contribute towards their high propulsive efficiency. However, the mechanistic basis of thrust augmentation by flexible propulsors remained unresolved, so the impact of bell margin flexibility on medusan swimming has also remained unresolved. We used biomimetic robotic jellyfish vehicles to elucidate that propulsive thrust enhancement by flexible medusan bell margins relies upon fluid dynamic interactions between entrained flows at the inflexion point of the exumbrella and flows expelled from under the bell. Coalescence of flows from these two regions resulted in enhanced fluid circulation and, therefore, thrust augmentation for flexible margins of both medusan vehicles and living medusae. Using particle image velocimetry (PIV) data we estimated pressure fields to demonstrate a mechanistic basis of enhanced flows associated with the flexible bell margin. Performance of vehicles with flexible margins was further enhanced by vortex interactions that occur during bell expansion. Hydrodynamic and performance similarities between robotic vehicles and live animals demonstrated that the propulsive advantages of flexible margins found in nature can be emulated by human-engineered propulsors. Although medusae are simple animal models for description of this process, these results may contribute towards understanding the performance of flexible margins among other animal lineages.

Item Type:Article
Related URLs:
URLURL TypeDescription CentralArticle
Colin, Sean P.0000-0003-4463-5588
Costello, John H.0000-0002-6967-3145
Dabiri, John O.0000-0002-6722-9008
Gemmell, Brad J.0000-0001-9031-6591
Additional Information:© 2012 Colin et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Received July 18, 2012; Accepted October 8, 2012; Published November 7, 2012. This work was supported by an ONR MURI award to SP (N000140810654) and National Science Foundation grant OCE 0623508 to JHC, SPC, JOD. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. We wish to thank Colin Smith for his help videoing the robotic jellyfish and Richard Satterlie for insightful conversations about the neuromuscular biology of jellyfish. We thank the New England Aquarium for their contributions of cultured medusae. Author Contributions: Conceived and designed the experiments: SPC JHC AV SP JBB. Performed the experiments: SPC JHC AV BJG. Analyzed the data: SPC JHC JOD BJG. Contributed reagents/materials/analysis tools: AV SP. Wrote the paper: SPC JHC.
Funding AgencyGrant Number
Office of Naval Research (ONR) MURIN000140810654
Issue or Number:11
PubMed Central ID:PMC3492145
Record Number:CaltechAUTHORS:20130131-142911383
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Official Citation:Colin SP, Costello JH, Dabiri JO, Villanueva A, Blottman JB, et al. (2012) Biomimetic and Live Medusae Reveal the Mechanistic Advantages of a Flexible Bell Margin. PLoS ONE 7(11): e48909. doi:10.1371/journal.pone.0048909
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:36720
Deposited By: Jason Perez
Deposited On:01 Feb 2013 00:14
Last Modified:09 Mar 2020 13:18

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