A foot/ground contact model for biomechanical inverse dynamics analysis

Area of Science:

• Biomechanics
• Human Motion Analysis
• Musculoskeletal Modeling

Background:

• Inverse dynamics simulation is crucial for analyzing human motion.
• Force platforms accurately measure ground reaction forces (GRF) but are limited by availability.
• Existing methods to estimate GRF without force platforms often require complex foot-ground contact models.

Purpose of the Study:

• To develop a more efficient method for computing ground reaction forces (GRF).
• To utilize a simplified, unilaterally constrained foot model at the center of pressure.
• To avoid the need for foot-ground contact compliance data.

Main Methods:

• Employed a unilaterally constrained foot model at the center of pressure.
• Used kinematic data combined with a simplified foot-ground contact model.
• Handled force estimation indeterminacy via a least squares approach with filtering.

Main Results:

• Achieved a relative root mean square error (rRMSE) of 4.1% for vertical GRF.
• Obtained an rRMSE of 11.2% for the anterior GRF component.
• Reported an rRMSE of 5.3% for the sagittal plane ground reaction moment (GRM).

Conclusions:

• The proposed model offers an efficient and simplified approach to estimate GRF.
• This method accurately computes GRF and GRM without requiring force platforms or foot-ground compliance data.
• The findings support the use of this model for broader applications in human motion analysis.