Ph.D. Proposal Presentation by Mark Holdhusen
Wednesday, October 29, 2003

(Dr. Ken Cunefare, advisor)

"The State-Switched Absorber Used For Vibration Control of Continuous Systems"


In recent years, much research has focused on vibration reduction by means of semi-active and active control of vibration absorbers. One such semi-active vibration control device is a state-switched absorber (SSA). A state-switched absorber is a mass-spring-damper device that is capable of instantaneously switching between discrete stiffnesses, thus changing its resonance frequency. Through proper control logic, the SSA can reduce the motion of the base to which it is attached, especially when the excitation contains more than one frequency component. The proposed research will consider an SSA applied to continuous beam and plate systems. A numerical model of each system will be employed to determine the optimum performance of the SSA. Physical parameters such as tuning frequencies, location, and number of absorbers will be considered in determining the optimum performance of each system. The performance of each system will also be validated experimentally. State-switched absorbers may be fabricated using a magneto-rheological (MR) elastomer, which can alter its stiffness depending on the magnetic flux across it. Utilizing a DSP system to control the state-switched absorbers, the experimental performance of the SSA will be determined and compared to the numerical models. The performance of the SSA will be compared to that of a classical tuned vibration absorber.