Modelling and Identification of Soft Pads for Robotic Fingers

Introduction. In this work the dynamic contact of a hemispherical indenter covered by a thick viscoelastic layer and pressed against a flat rigid surface is modeled. The goal is to investigate the dynamic behavior of robotic fingertips composed by an inner rigid structure covered by a soft layer, mimicking the human biological model. A quasi-linear model, frequently used to describe the behavior of soft and pulpy biological tissues, is adopted in order to achieve a compromise between the simplicity of classical linear models and the difficulty of nonlinear approaches. Two different materials (a polyurethane gel and a silicon rubber) have been tested experimentally.