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10:52
Simulation of Human-induced Vibrations Based on the Characterized In-field Pedestrian Behavior
Published on: April 13, 2016
Dynamic stability of passive dynamic walking on an irregular surface.
Jimmy Li-Shin Su1, Jonathan B Dingwell
1Department of Biomedical Engineering, University of Texas, 1 University Station, D3700, Austin, TX 78712, USA.
Journal of Biomechanical Engineering
|December 11, 2007
Summary
Walking surface variability increases kinematic variability and local instability, predicting fall risk. Orbital stability remained unchanged, highlighting the importance of local measures for assessing walking stability and fall prevention.
Area of Science:
- Biomechanics
- Robotics
- Human movement analysis
Background:
- Falls during walking pose a significant health risk.
- Quantifying walking stability is challenging due to a lack of standardized methods.
- Variability measures do not fully capture locomotor system responses to perturbations.
Purpose of the Study:
- To investigate how walking surface variability influences locomotor variability and stability.
- To differentiate between various measures of walking stability and their relation to fall risk.
Main Methods:
- A simplified walking model was used with simulated surface perturbations.
- Orbital stability was assessed using Floquet multipliers.
- Local stability was quantified by local exponential rates of divergence.
- Kinematic variability was analyzed across varying perturbation amplitudes.
Main Results:
- Increased surface perturbation amplitude led to exponential increases in kinematic variability.
- Short-term local instability increased linearly with perturbation amplitude.
- Orbital stability and long-term local instability showed no significant changes.
- Measures of kinematic variability and short-term local instability predicted increased fall risk.
Conclusions:
- Kinematic variability and short-term local instability are sensitive indicators of increased fall risk.
- Orbital stability alone is insufficient for assessing walking stability under perturbed conditions.
- Distinguishing between local and orbital stability is crucial for understanding fall mechanisms.
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