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A model to predict ground reaction force for elastically-suspended backpacks
Yuquan Leng1, Xin Lin1, Zeyu Lu1
1Department of Mechanical and Energy Engineering, Southern University of Science and Technology, Shenzhen 518055, China.
Gait & Posture
|September 18, 2020
Summary
An elastically-suspended backpack (ESB) model accurately predicts leg ground reaction forces (GRF) during walking. The ESB can positively or negatively impact GRF based on its parameters, offering design insights.
Area of Science:
- Biomechanics
- Human locomotion
- Wearable technology
Background:
- Leg muscle fatigue significantly impacts walking endurance.
- Ground reaction force (GRF) indirectly reflects leg muscle strength during walking.
- The effect of elastically-suspended backpacks (ESBs) on leg GRF during walking is not well understood.
Purpose of the Study:
- To investigate the relationship between ESBs and leg GRF during walking.
- To determine how ESB variables (stiffness, damping, load mass, walking speed) influence GRF.
Main Methods:
- An extended bipedal walking (EBW) model with a spring-mass-damping system was developed to predict GRF.
- Experiments were conducted with seven healthy subjects walking at various speeds and load conditions (12 conditions total).
- Model predictions were compared against experimentally measured GRF data.
Main Results:
- The EBW model accurately predicted experimental GRFs (R² ≥ 0.9628) and characteristic forces (93.7% average accuracy).
- The model revealed relationships between ESB variables and GRF, indicating a trade-off among characteristic forces.
- ESB effects on GRF can be positive or negative depending on specific parameter settings.
Conclusions:
- The developed model provides a quantitative understanding of GRF phenomena during walking with an ESB.
- Findings can guide the optimization of ESB structural parameters for enhanced human performance.
- Optimized ESBs have potential applications in military and tourism industries.
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