Consumer Product Design for Tactile Perception: Multiphysics and Variability in the Finger-Material Interface

Design of products for pleasant or luxurious feeling is important within the consumer products industry, yet this is mostly still a trial-and-error activity. Friction reduction through texture is often the approach, yet the interface is complex due to multiphysical phenomena such as capillary bridges formed by sweat, deformation and contact as well as the textures ranging from macroscale to nanoscale on both surfaces. The universal existence of lipids and sebum makes the friction force and the tactile feeling of the textured surface more difficult to understand and predict by affecting the interface in different ways. In this work, a multiphysics model was employed to model and elucidate the underlying physics and mechanisms of the interface at the single asperity level.