Generating Facial Expressions Using an Anatomically Accurate Biomechanical Model.

Area of Science:

• Computational biomechanics
• Human facial expression modeling
• Finite element analysis

Background:

• Accurate modeling of human facial expressions is crucial for understanding biomechanics.
• Previous models often simplify complex soft tissue and muscle interactions.
• High-fidelity computational models are needed to capture intricate facial dynamics.

Purpose of the Study:

• To develop a computational framework for modeling human facial expression biomechanics.
• To incorporate detailed anatomical data and material properties into a finite element model.
• To investigate the impact of material heterogeneity and contact interactions on expression simulation.

Main Methods:

• Constructed a high-order finite element model of the human head using MRI data.
• Included skin, subcutaneous layer, and superficial Musculo-Aponeurotic system.
• Modeled 20 pairs of facial muscles with accurate geometry and fiber orientation, treating them as transversely-isotropic.
• Incorporated material heterogeneity and complex contact interactions between soft tissues and bone.

Main Results:

• Simulated four distinct facial expressions using the developed model.
• Achieved good agreement between predicted expressions and experimental surface data from a 3D scanner.
• Demonstrated the significance of including material heterogeneity and contact interactions.

Conclusions:

• The developed computational framework provides a robust tool for biomechanical analysis of facial expressions.
• The study highlights the importance of detailed anatomical and material properties for accurate facial modeling.
• Findings support the use of advanced finite element models for simulating complex biological systems.