Active Structural Acoustic Control of Clamped Flat Plates Using a Weighted Sum of Spatial Gradients

Abstract

The weighted sum of spatial gradients (WSSG) control minimization parameter is developed for use in active structural acoustic control (ASAC) on a clamped flat rectangular plate. The WSSG minimization parameter is measured using four accelerometers grouped closely together on the test structure. In previous work, WSSG was developed on a simply supported flat rectangular plate and showed promise as a control metric. The displacement on the clamped plate has been modeled using an approximate analytical solution assuming shape functions corresponding to clamped-clamped beams. From the analytical formulation, weights, which were found to be the reciprocal of the wave number squared, have been derived to produce a uniform WSSG field across the plate. In active control simulations, this quantity has been shown to provide better global control of acoustic radiation than volume velocity. Analysis is presented which shows that comparable control, regardless of the sensor location, can be achieved using WSSG. Experimental results are presented which demonstrate that WSSG works effectively in practice, with results similar to the simulations. The results show that minimization of WSSG can be used as an effective control objective on clamped rectangular plates to achieve attenuation of acoustic radiation.

Active control of cylindrical shells using the weighted sum of spatial gradients control metric

“…Gradients" (WSSG) in order to more accurately describe the quantity, since the velocity gradients were in fact based on the spatial derivatives of the vibration field. This method has also been investigated for the case of a clamped plate, as well as for a ribbed plate [55]. The experimental results suggest reasonable agreement between the modeled control and the experimental results.…”

“…Note the very small range on the color axis. metric was then developed for the case of flat panels or plates[53][54][55].…”

Active control of simply supported cylindrical shells using the weighted sum of spatial gradients control metric

“…In subsequent work, this method was implemented on planar structures, and the error metric was referred to as WSSG. [18][19][20][21] This paper presents the extension of the WSSG method to curved structures, and specifically applies the method to a simply supported cylindrical shell, with the objective of fulfilling the criteria mentioned above for practicality and convenience. For curved structures, the membrane and bending stresses are coupled, and this work investigated whether the WSSG method would still work effectively given this difference in the dynamic response.…”