Modelling of finger-surface contact dynamics

• A model to describe vibration induced from scanning a finger on a surface is developed.
• The model considers contacts between asperities as Hertzian contacts.
• The method allows to clarify how surface periodic roughness is perceived.
• Experimental validation is provided.
• The influence of the contact load on the induced vibration is shown.

The tactile perception of a surface texture originates from the scanning of a finger on the surface. This kind of sliding contact activates the mechanoreceptors located into the skin, allowing the brain to identify the object and to perceive information about the scanned surface. In this paper, a numerical model describing finger-surface scanning is introduced in order to investigate the relationship between contact induced vibrations and scanning conditions. The model takes into account finger and surface shapes, material properties, normal contact force, and scanning velocity. Model validation is provided by comparison with experimental tests. Afterwards, the model is applied to clarify the role played by contact/scanning parameters on the induced vibration. The proposed model is useful to develop a comprehensive parametrical analysis of the vibration induced in finger-surface scanning, and to investigate the influence of material and contact properties on tactile perception.