<p>Recent scientific advances in the field of nonlinear periodic metastructures have shown significant potential for improved vibration attenuation in various types of structures. This work investigates the potential benefits of applying this concept to rotating structures. The results of a numerical analysis are presented showing the effects of applying an array of bi-stable disk oscillators on the mid-span of a rotating shaft. Each oscillator is modeled as a 1D Duffing oscillator, and a synchronous rotating force is applied to one of the shaft ends, while the vibration response is evaluated at the opposite shaft end. The attenuation performance is evaluated under forward, backward, and unbalanced excitation conditions, comparing the results with those obtained with linear resonators. A novel Modally Matched Distribution (MMD) approach for improved oscillator placement is proposed and shown to achieve significant improvements in attenuation performance, with an increase of over 100% in attenuation bandwidth. The forward and backward vibration components, which are usually decoupled in linear isotropic rotors, are coupled as an effect of the introduced nonlinearity. The findings revealed that non-linear oscillators consistently improve attenuation for frequencies immediately below the linear bandgap range, especially upon the occurrence of chaotic behavior. However, for frequencies above this range, the performance remained unchanged or, in some cases, deteriorated. A strategy for limiting these adverse effects is also proposed and investigated. With the aid of full-spectrum analysis of the rotor’s chaotic whirl response, the underlying phenomena involved in chaotic vibration attenuation are also discussed.</p>