A tribological investigation of cochlear implant electrode arrays with different wire shapes

The elasticity and frictional dynamics of a cochlear implant electrode array (EA) with different wire shapes are investigated by numerical and experimental analysis. Finite element method (FEM) analysis with varying wavelengths under large deformations indicates that the corrugated wire exhibits enhanced flexibility in both the transverse and longitudinal directions, while the buckling limit of the EA is governed by the wavelength of the wires. The friction experiments are carried out on a flat surface and an artificial cochlea model at different preloads, speeds and surface conditions, and the resulting data are analyzed using friction loops. It is found that wavy wired EA has a lower friction response and insertion force, while they are more prone to tip buckling and electrode array tip fold-over.