Application of the Taguchi Method to Sensitivity Analysis of a Middle-ear Finite-Element Model

Abstract

Sensitivity analysis of a model is the investigation of how outputs vary with changes of input parameters, in order to identify the relative importance of parameters and to help in optimization of the model. The one-factor-at-a-time (OFAT) method has been widely used for sensitivity analysis of middle-ear models. The results of OFAT, however, are unreliable if there are significant interactions among parameters. This paper incorporates the Taguchi method into the sensitivity analysis of a middle-ear finite-element model. Two outputs, tympanic-membrane volume displacement and stapes footplate displacement, are measured. Nine input parameters and four possible interactions are investigated for two model outputs. For the tympanic-membrane volume displacement, the contributions from the Young’s modulus and thickness of the pars tensa are dominant. For the footplate displacement, several input parameters play important roles and a strong interaction exists between the Young’s moduli of the incudomallear and incudostapedial joints. It is important to take this interaction into account when the parameters' effects on model behaviour are being considered.