Assessment on the contact factors of a sandwich soft finger model – An experimental investigation

Abstract

Abstract The bio-mechanics of skin and bone play a crucial role in dexterous object manipulations and artificial robotic gripper design. Establishing a quantitative relationship between imposed loads and contact factors is necessary to understand the governing mechanics behind it. Towards this goal, experimental investigations on the contact parameters of a sandwich soft fingertip comprising a soft layer and solid core are presented. The influence of soft layer stratum and material grades on the power law equation is investigated by introducing a new dimensionless parameter – Power Factor. The results clearly indicate that the power index “ γ ” is dependent on the material as well as shell thickness and in addition the proportionality constant “ C ” is dependent on the geometry. Also, the magnitude of both the constants increases with power factor and saturates at a value of ≈1.25. Numerical simulation is performed to support the experimental results. Finally, an optimum ratio of power factor is determined and the number ≈1.25 is critical in designing the artificial robotic sandwich fingertip.