Abstract
In previous studies, a newly developed stability analysis method based on the existence condition of boundaries between stable and unstable regions was applied to contact rotating systems in which all time delay are the same in order to analyze pattern formation phenomena. This analysis method can be carried out efficiently and accurately without the need to obtain characteristic roots. In this report, we attempt to apply this analysis method to a system including different time delays. The effectiveness of the proposed method is then verified with results calculated numerically by comparison with exact results of general method using characteristic roots from an example of 3 DOF system with 4 rolls, which comprises two viscoelastic rolls with different diameters leading to different time delays.
