Active Structural Acoustic Control (ASAC) is a subcategory of the more widely known field of Active Noise control (ANC). ASAC is different from traditional ANC methods because it seeks to attenuate noise by altering the noise producing structure instead of altering the acoustic waves traveling through the air. The greatest challenge currently facing ASAC researchers is that a suitable parameter has not yet been discovered which can be easily implemented as the minimization quantity in the control algorithms. Many parameters have been tried but none effectively attenuate the sound radiation in a way that can be easily implemented. A new parameter was recently developed which showed great potential for use as a minimization quantity. This parameter has been termed the "weighted sum of spatial gradients" (WSSG) and was shown by previous researchers to significantly reduce noise emissions from a vibrating simply supported plate in computer simulations. The computer simulations indicate that WSSG-based control provides as good or better control than volume velocity and does so with a single point measurement which is relatively insensitive to placement location. This thesis presents the experimental validation of the WSSG computer simulations. This validation consists of four major components. First, additional research was needed in to extend the use of WSSG from computer simulations to experimental setups. Second, the WSSG-based control method was performed on simply supported plates to validate the computer simulations. Third, the WSSG-based control method on was used on clamped plates to validate the computer simulations, and fourth, the WSSG-based control method was validated on plates with ribs. The important results are discussed and conclusions summarized for each of these sections. Recommendations are made for future work on the WSSG parameter.



College and Department

Ira A. Fulton College of Engineering and Technology; Mechanical Engineering



Date Submitted


Document Type





ASAC, ANC, vibration control, active control of structures, independent radiation modes, experimental WSSG, simply supported plate, clamped plate, ribbed plate, Daniel R. Hendricks