Quantifying the Frictional Forces between Skin and Nonwoven Fabrics

Area of Science:

• Biomechanics
• Materials Science
• Friction Studies

Background:

• Frictional forces on curved surfaces can exceed those on planar interfaces, contributing to skin abrasion in vulnerable populations.
• Current methods to quantify these forces often rely on simplified capstan-type equations.
• These equations may overlook crucial geometric and physical factors influencing friction.

Purpose of the Study:

• To develop and present mathematical models for computing material displacements and surface forces.
• To analyze the contact mechanics of a tensioned membrane on a rigid obstacle and a shell-membrane on a deformable substrate.
• To evaluate the accuracy of capstan models in predicting frictional behavior under various conditions.

Main Methods:

• Development of two distinct mathematical models.
• Simulation of a membrane under tension in contact with a rigid obstacle.
• Simulation of a shell-membrane under tension in contact with a deformable substrate.

Main Results:

• Capstan equations show robustness in some scenarios but can be inaccurate.
• Factors like underlying body curvature, flaccidness, and fabric mass density significantly affect contact stresses.
• The coefficient of friction derived from capstan models may not precisely represent true frictional behavior.

Conclusions:

• The simplified capstan model is insufficient for accurately characterizing friction in complex curved contact scenarios.
• Accurate friction assessment requires considering the geometry and physical properties of both the contacting materials and the underlying body.
• Further research into advanced modeling is needed for precise friction quantification in biomedical and material applications.