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Hair receptor sensitivity to changes in laminar boundary layer shape
1Air Force Research Laboratory, Munitions Directorate, Eglin Air Force Base, FL 32542, USA. btdickinson@lifetime.oregonstate.edu
Bioinspiration & Biomimetics
|February 17, 2010
Summary
Bat wings use specialized hair receptors to detect airflow changes, enhancing flight stability. Optimal hair geometry, like tapering, maximizes sensitivity, guiding artificial sensor design.
Area of Science:
- Aerodynamics
- Biomechanics
- Sensory Biology
Background:
- Bat wings possess distributed arrays of flow-sensitive hair receptors.
- These receptors are hypothesized to provide sensory feedback on airflow for flight control.
Purpose of the Study:
- Investigate the geometric specialization of hair-like structures for detecting boundary layer velocity profile changes.
- Determine optimal hair geometry for maximizing sensitivity to airflow variations.
Main Methods:
- Developed a quasi-steady model linking flow velocity profiles to hair base forces (moment and shear).
- Analyzed the relationship between hair length, boundary layer momentum thickness, and sensitivity to profile shape changes.
Main Results:
- Hair sensitivity to airflow changes is highly dependent on hair length.
- Linearly tapering hairs exhibit greater output sensitivity compared to uniform cross-section hairs.
- Computed optimal hair lengths align with measured bat hair receptor lengths.
Conclusions:
- Results support the hypothesis that bats utilize hair receptors for detecting boundary layer shape changes.
- Provides geometric design principles for artificial hair sensors.
- Highlights the role of hair receptor geometry in bat flight dynamics.
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