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06:08
Biophysical Characterization of Flagellar Motor Functions
Published on: January 18, 2017
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Numerical exploration on buckling instability for directional control in flagellar propulsion
1Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, Los Angeles, California 90095, USA. khalidjm@seas.ucla.edu.
Soft Matter
|December 25, 2019
Summary
Bacteria and bio-robots can steer by using flagellar buckling instability. This controlled instability allows precise directional changes in microswimmers, mimicking natural bacterial navigation.
Area of Science:
- Biophysics
- Robotics
- Fluid Dynamics
Background:
- Uniflagellar bacteria and bio-inspired robots navigate fluids using flagellar propulsion.
- Locomotion involves complex interactions between flagellar elasticity, hydrodynamics, and head motion.
- Controlling direction at low Reynolds numbers presents a significant challenge.
Purpose of the Study:
- To develop a numerical method for controlling swimming direction in flagellated microswimmers.
- To investigate the role of flagellar buckling instability in directional control.
- To solve the inverse problem of determining control parameters for desired trajectories.
Main Methods:
- Utilized the Discrete Elastic Rods algorithm for flagellar deformation.
- Applied Lighthills Slender Body Theory for hydrodynamic simulations.
- Employed Higdons model for the motion of a spherical head in viscous fluid.
Main Results:
- A critical angular velocity threshold was identified for flagellar buckling.
- Below the threshold, swimming is straight; beyond it, nonlinear trajectories emerge.
- The study successfully computed time-varying angular velocities for desired nonlinear paths.
Conclusions:
- Flagellar buckling instability is a viable mechanism for precise directional control in microswimmers.
- Bacteria can exploit this natural instability for navigation.
- The numerical method provides a framework for designing bio-inspired robots with enhanced maneuverability.
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