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Updated: May 30, 2026
09:24
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Published on: January 28, 2020
Stochastic low Reynolds number swimmers.
Ramin Golestanian1, Armand Ajdari
1Department of Physics and Astronomy, University of Sheffield, Sheffield S3 7RH, UK.
Summary
Researchers developed a theoretical framework for stochastic motors to propel micro-swimmers using random motion. This approach enables directed movement for low Reynolds number swimmers, crucial for nanoscale applications.
Area of Science:
- Physics
- Biophysics
- Nanotechnology
Background:
- Autonomous micro-swimmers face challenges in achieving directed propulsion using deterministic methods at low Reynolds numbers.
- Future advancements require strategies that harness random conformational changes for directed motion.
Purpose of the Study:
- To present a theoretical formulation for a 'stochastic motor' to drive low Reynolds number swimmers.
- To investigate the propulsion of a three-sphere swimmer model using this stochastic motor concept.
Main Methods:
- Developed a theoretical framework for stochastic motors operating out of equilibrium.
- Applied the formulation to a simplified three-sphere swimmer model.
Main Results:
- Demonstrated that breaking detailed balance and driving the motor out of equilibrium enables directed propulsion.
- The stochastic motor can effectively propel the swimmer in a desired direction.
Conclusions:
- The theoretical formulation provides a viable method for generating directed motion in micro-swimmers.
- This approach is applicable for optimizing the design of molecular-scale low Reynolds number swimmers.
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