Robustness Analysis of MIMO Mechatronic Systems in the Frequency Domain

Abstract

A new and general method of robustness analysis for linear dynamic systems containing both electrical and mechanical components is proposed in this paper. The method is based on the convex optimization theory and, therefore, it is accurate, efficient, and scales well with the number of unknown variables. The method is applied to two examples: a piezoelectric harvester (single-input single-output case) and a double mass–spring–damper system (multiple-input multiple-output (MIMO) case). In both cases, upper and lower bounds of the magnitude response are computed and compared to the Monte Carlo method. The results show that parametric variation affect strongly the performance output, uncertainty must be taken into account for a robust design, and that the proposed method is a great improvement to the existing method in the literature.