USA As Represented by Secretary of the Navy

John A Sterling

David M Pickett

Stephen Paul Ebner

Dana Colegrove

Joseph F Vignola

Daniel Richard Nashold

Michael George Hanback

Paul Michael Strano

An exemplary inventive subordinate oscillator array (SOA) includes two or more vibration attenuation devices (oscillators) that are sequentially arranged (e.g., via beams in the SOA) so that their respective anti-vibratory influences overlap. To design the SOA, an optimal number N of oscillators is calculated according to the equation N=&#x3b7;Q&#x394;, where &#x3b7; is the modal overlap, Q is the quality factor, and &#x394; is the desired fractional bandwidth. Each oscillator is akin to a conventional dynamic vibration absorber (DVA) and is characterized by its own mass, stiffness, damping, and geometry (e.g., length, width, and height). The respective characteristics of the oscillators are selected and the oscillators are distributed so that the SOA, when suitably attached to a vibrative structure, attenuates the vibrations of the structure so as to approximately flatten the structure's vibrations over a frequency band of interest.

Manufacture methods relating to a subordinate oscillator array

A typical inventive device is self-contained and is designed for adjunctive placement at the unconnected end of a towed body in order to test dynamic motions of the towed body. The inventive device includes an IMU, a computer, wired/wireless communication electronics, a fluid-dynamically shaped member, and a cylindrical housing (which encloses the IMU, the computer, and the communication electronics). The housing is connected to the towed body aft of the towed body, and the shaped member is connected to the housing aft of the housing. Data is acquired that is indicative of the inertial dynamics of the towed body while in motion through a fluidic medium. Differently shaped members can be independently connected to the housing at different times, each influencing in its own way the inertial dynamics of the towed body and yielding its own set of data. Comparisons can thus be drawn between/among differently shaped members.

Inertial dynamics measurement and structural configuration variation for hydrodynamic stability evaluation of a towed body

Growing community of inventors

McLean, VA, United States of America

John A Sterling