A superellipsoid-plane model for simulating foot-ground contact during human gait.

Area of Science:

• Biomechanics
• Computational modeling

Background:

• Musculoskeletal models and forward dynamics simulations of human movement rely on accurate foot-ground contact force calculations.
• Current methods often use point-plane elements, but comparisons with other geometric solutions are limited.

Purpose of the Study:

• To develop a general-purpose superellipsoid-plane contact model for determining 3D foot-ground contact forces.
• To compare the performance of this new model against a point-like viscoelastic contact model in human walking simulations.

Main Methods:

• Developed a superellipsoid-plane contact model for foot-ground interactions.
• Integrated the model into a forward dynamics simulation of human walking.
• Compared simulation results, execution times, and numerical stiffness with a point-like viscoelastic model.

Main Results:

• Both models produced realistic ground reaction forces and kinematics with similar computational efficiency.
• The superellipsoid-plane model was ~18% faster and ~37% less numerically stiff.
• Superellipsoid-plane elements allow for volumetric contact and are geometrically accurate.

Conclusions:

• Superellipsoid-plane contact models are a versatile and efficient alternative to point-like elements in musculoskeletal simulations.
• The developed model enhances the accuracy and computational performance of human movement simulations.
• This approach facilitates the integration of geometrically accurate contact elements within multibody simulation frameworks.