Microswimming, micropumping and microgliding

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Micro-swimming, micro-pumping and micro-gliding
With Oren Raz
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Outline

• Showtime
• Helices
• Cox for pedestrians
• Gauge and anchoring
• Triality Pumps, swimmers gliders
• Optimal anchoring
• Efficiency swimmers and pumps

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Organisms vs robots

• Interface with macroscopia
• Umicrobot100 x Ubacteria
• Pmicrobot104 x Pbacteria
• Small batteries

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Showtime Robot race
Robot race
Najafi and Golestanian, 2004
Euglena
http//lifesci.rutgers.edu/triemer/movies.htmMet
aboly
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Generic strokes swim
Purcell
NG 3 linked spheres
Distance Area in control space
pushmepullyou
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Swimming and parking
Parksteer,drive
Nelson, J.P. Eckmann
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Showtime Sysiphus
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Swimming in quiescent fluid

• Generic strokes swim
• Generic swimming is sysiphian
• Effective swimming is quiescent
• Anchor as an engine

pushmepullyou
Treadmiller
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Helices vs corkscrew
Pitch in many turns
Pitch in one turn
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Helices are Sysiphian
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Pitch to suit purpose

• Optimal swimming speed q54.7
• Optimal pumping force q45
• Optimal swimming power q49.9
• Optimal pumping power q42.9

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Cox for pedestrians
Slender swimmer
Ratio of drag on a needle in 21
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Swimming and pumping

• Swimming equation F0
• Pumping equation X0

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Gliding ants
http//www.canopyants.com/
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Optimal gliding
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Swimming, pumping gliding
Pumping, like swimming, is geometric
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Triality
Lorentz reciprocity
Ehud Yariv, Howard Stone, S Samuel
You can swim for free but you cant pump for free
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Gauge and anchoring
Euclideantranslation rotation
Pumps the other way
Pumps one way
Thm For linear swimmers optimal anchoring is at
the joints
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Efficiency swimmers
With normalized stroke period
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Efficiency pumps
With normalized stroke period
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• Thanks A. Leshanski, O. Kenneth, D. Oaknin, O.
  Gat, H. Stone,