Experimental analysis of vibration confinement to enhance conventional active vibration control

This paper presents the results of an experimental study to investigate the potential advantages of using passive vibration confinement over conventional active vibration control methods, as well as to investigate the benefits of using the two methods simultaneously. The general approach is to compare the results of actively controlling vibrations in a beam which sees various degrees of modal confinement. Vibration confinement is carried out passively, and the comparison is based on control effort required as well as vibration control performance achieved. To date, there has been a significant amount of work in the area of vibration confinement, or mode localization, but the focus has been primarily either 1) that it is an interesting phenomenon which exists in structures or 2) that it can be produced in structures through active, passive, or hybrid means to achieve some end such as vibration control. This paper presents an experimental follow-up to an earlier numerical study which directly compared confinement techniques to conventional active vibration control methods, and showed how confinement can be used to enhance conventional vibration control. Although not as dramatic, the results presented in this paper clearly support that study and show that passive vibration confinement can enhance active control through both performance and energy consumption.