Application of Tuned Mass Damper to Address Discrete Excitation Away From Primary Resonance Frequency of a Structure

Tuned mass dampers (TMDs) or vibration absorbers are widely used in the industry to address various NVH issues, wherein, tactile-vibration or noise mitigation is desired. TMDs can be classified into two categories, namely, tuned-to-resonance and tuned-to-discrete-excitation. An overwhelming majority of TMD applications found in the industry belong to the tuned-to-resonance category, so much of information is available on design considerations of such dampers; however, little is published regarding design considerations of dampers tuned-to-discrete-excitation. During this study, a problem was solved that occurred at a discrete excitation frequency away from the primary resonance frequency of a steering column-wheel assembly. A solution was developed in multiple stages. First the effects of various factors such as mass and damping were analyzed by using a closed-form solution. Once the initial design guidelines were obtained, prototype parts were built to quantify the in-situ benefit of the damper at the desired frequency. Finally, the effect of production variability was studied by measuring a larger population of randomly selected parts. The findings of the study provide important clues to the utility and limitations of dampers tuned-to-discrete-excitation.