Investigation on the use of clustered tuned mass absorbers to address target mode variability

Many dynamic structures are engineered to sustain a relatively long fatigue life. In these cases, the structural stiffness requirements are critical for maintaining an acceptable level of vibration response and fatigue stress. However, the structural stiffness is also accompanied by mass, which for many dynamic structures can degrade efficiency or performance.;Therefore, the control of vibration response fatigue stress is studied using a single tuned mass absorber. The vibration response attenuation from a single tuned mass absorber enables the opportunity to reduce the structural stiffness (and mass), thus producing an overall lighter design while maintaining fatigue stress of the heavier design.;Although a single tuned mass absorber is a well-known device that can achieve vibration response attenuation, it is limited to a particular frequency of the primary structure. Since the natural frequency of many dynamic structures can change, the implementation of multiple tuned mass absorbers in an array in close proximity of the main structural mode is also studied. The array of tuned absorbers are tuned to cover a band of frequencies where the primary structure's mode exists but in recognition that the primary frequency may have variation. Attenuation metrics are developed to characterize the effectiveness of the various tuned mass absorber implementations studied.