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Published on: April 13, 2011
Is the behaviour of the leg during oscillation linear?
V A Coveney1, G D Hunter, J Spriggs
1Faculty of Engineering, University of the West of England, Frenchay Campus, Coldharbour Lane, Frenchay, Bristol BS16 1YQ, UK. vince.coveney@uwe.ac.uk
Journal of Biomechanics
|July 27, 2001
Summary
Human leg stiffness increases during oscillation, as shown by free vibration tests. This study reveals non-linear characteristics in leg biomechanics, suggesting improved models for future research.
Area of Science:
- Biomechanics
- Human Physiology
Background:
- Understanding the mechanical properties of the human leg is crucial for biomechanical analysis and injury prevention.
- Previous models often simplify leg behavior as linear, potentially missing important dynamic characteristics.
Purpose of the Study:
- To investigate the dynamic behavior of the human lower leg using a free oscillation method.
- To determine if the human leg exhibits linear or non-linear characteristics under vibratory loads.
Main Methods:
- Employed a free oscillation technique to study the human lower leg.
- Utilized a simple mass, spring, and dashpot model to represent the lower leg.
- Conducted free vibration tests on 45 subjects' right legs, measuring force amplitude and oscillation time periods.
Main Results:
- Calculated stiffness-to-mass ratio values from successive oscillation cycles.
- Observed a significantly lower time period in the second oscillation cycle compared to the first.
- This decrease in time period indicates a corresponding increase in leg stiffness during oscillation.
Conclusions:
- The experimental data consistently demonstrates non-linear characteristics in human leg behavior during free oscillation.
- The findings suggest that linear models may be insufficient for accurately capturing leg dynamics.
- Future free oscillation studies could benefit from employing non-linear biomechanical models for enhanced accuracy.
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