Evaluating Disruptive Tuned Mass Vibration Attenuators in Rotary Wing Applications

This paper examines the performance of passive structural vibration attenuating devices in rotary wing applications and introduces a new attenuating device to rotary wing applications, the NASA-developed Disruptive Tuned Mass (DTM) device. The testbed uses an OH-58D tailboom rigidly mounted to the floor as a cantilever beam with a first lateral mode resonant frequency of approximately 6.25 Hz as a representative rotary wing structure. The study characterizes the modal response of the tailboom without an attenuating device installed, with additional mass installed, a mass-spring attenuating device, a fixed orifice Tuned Mass Damper (TMD), and a device based on NASA DTM technology. TMD and DTM devices were tested with 6 lbs (2.72 kg) and 19 lbs (8.61 kg) mitigation masses. The DTM devices achieved greater modal attenuation than the TMD devices, 88% and 96% respectively, for devices with 6 lbs (2.72 kg) and 19 lbs (8.61 kg) active masses.