Date of Award


Degree Type



Mechanical Engineering

First Advisor

Sawicki, Jerzy

Subject Headings

Rotors -- Dynamics, Robust control


It is well recognized that analytical models only approximate the true dynamics of analyzed rotating machines, due to the presence of components that are inherently difficult to model. Such models of rotating machines are driven by the best engineering knowledge and experience, and very often are updated based on experimental results. The problem of unmodeled or missing dynamics can be exacerbated in the presence of rotor structural damage such as a transverse crack on a shaft. This thesis will present an effective approach for model updating using advanced tools developed in robust control theory, specifically mu-synthesis. The methodology will be introduced based on a simple three-mass system and then applied to identification of the minute changes in the dynamics of the rotor test rig due to the presence of a transverse crack. Experimental data collected from the cracked rotor rig will be utilized to validate the developed approach