Investigation of friction mechanisms during the sliding of elastomers against hard parallel-ridge textures

Skin friction against textured surfaces is of great interest in a number of products. Primary challenges in haptics are measuring skin friction against textures and characterizing complex textures. The authors sought to measure the coefficient of friction of skin-simulating elastomers against a number of polypropylene textures. All the textures involved arrays of parallel ridges characterized by ridge width, pitch, and height. The first part of the work investigated silicone friction against a non-textured panel. The second part involved neoprene friction both parallel and perpendicular to the texture ridges. Neoprene COF depended strongly on the textures′ raised area fraction in parallel sliding. There was a ridge height threshold below which friction was equivalent in either sliding direction.