Multibody Model with Foot-Deformation Approach for Estimating Ground Reaction Forces and Moments and Joint Torques...

Area of Science:

• Biomechanics
• Motion Analysis
• Human Movement Science

Background:

• Traditional biomechanical models for estimating ground reaction forces (GRFs) and ground reaction moments (GRMs) often require extensive computational time due to optimization processes.
• Existing methods may also rely on training data or specific gait assumptions, limiting their general applicability.

Purpose of the Study:

• To develop a novel optical motion capture (OMC)-based method for estimating GRFs, GRMs, and joint torques.
• To overcome the challenge of long computational times associated with traditional biomechanical modeling approaches.

Main Methods:

• A new OMC-based method was developed, utilizing a multibody model to distribute external forces between the feet based on foot deformation.
• This approach predicts GRFs and GRMs without employing optimization techniques, thereby reducing computational load.
• The method was validated during level walking by comparing its estimations with force plate measurements.

Main Results:

• The proposed OMC-based method demonstrated excellent or strong correlations for all estimated GRFs, GRMs, and lower-limb joint torques compared to force plate data.
• Prediction accuracies were confirmed during level walking, validating the method's effectiveness.
• The approach significantly reduced computational time compared to traditional optimization-based methods.

Conclusions:

• The developed OMC-based method provides a practical and computationally efficient solution for estimating GRFs, GRMs, and joint torques.
• This technique facilitates rapid biomechanical analysis and feedback, enhancing its utility in clinical settings.
• The low computational cost and high accuracy make this method a valuable tool for biomechanical research and clinical applications.