Optimized design of lower limb exoskeleton based on human biomechanical analysis

Area of Science:

• Biomechanics
• Human-Machine Systems
• Orthotics and Prosthetics

Background:

• Exoskeleton R&D often neglects pre-prototype biomechanical impact analysis.
• This leads to extended design cycles and increased research and development costs.
• A simulation-driven approach is needed to optimize passive lower-limb exoskeleton design.

Purpose of the Study:

• To propose and validate a passive lower-limb exoskeleton optimization design method.
• To analyze the effects of structural parameters on human biomechanics.
• To reduce R&D costs and design time for exoskeleton development.

Main Methods:

• Developed a human-exoskeleton musculoskeletal coupling model in AnyBody software.
• Designed a subject-specific lower-limb exoskeleton model in SolidWorks.
• Performed inverse dynamics simulations to analyze effects of torsion spring stiffness on knee joint forces, metabolic rate, and muscle activation.

Main Results:

• Optimal torsion spring stiffness of 75 Nm/rad minimized knee joint forces and metabolic rate.
• Exoskeleton demonstrated significant reduction in lower limb muscle activation.
• Simulation data showed high correlation (R² > 0.976) with experimental surface EMG signals.

Conclusions:

• The proposed AnyBody-based simulation method enables low-cost, rapid design of passive lower-limb exoskeletons.
• Optimization of structural parameters like torsion spring stiffness can enhance exoskeleton assistive effects.
• Further experimental validation with physical prototypes is required to confirm theoretical findings.