Date of Award


Degree Type



Mechanical Engineering

First Advisor

Sawicki, Jerzy

Subject Headings

Rotors, Actuators, Vibration, rotor, vibration, active magnetic actuator


The purpose of this work was to develop and experimentally demonstrate a novel approach to minimize lateral vibrations of flexible rotor. The applied feed forward control approach employed magnetic force actuator to inject a specially designed force to counteract the rotor unbalance force. By specific selection of frequency and phase as functions of the rotor running speed and rotor natural frequency, the proposed simplified injection waveform has been shown to be effective both in reducing the rotor's vibrations and for hardware implementation. A model of the test rig was constructed using the finite element (FE) method and was validated using experimental data. The effectiveness of the proposed current injection was numerically simulated with FE model and experimentally validated using a residual unbalance force. It was noticed that at a selected constant running speed, just below the first rotor critical speed, the rotor vibrations were reduced approximately by 90 . The method was also implemented during the speed ramp test, which passes through the first critical speed. In this test the proposed force injection also reduced vibrations at various rotor speeds. These results agree well with the results of simulation