A double-panel active segmented partition module using decoupled analog feedback controllers: Numerical model

Abstract

Low-frequency sound transmission has long plagued the sound isolation performance of lightweight partitions. Over the past 2 decades, researchers have investigated actively controlled structures to prevent sound transmission from a source space into a receiving space. An approach using active segmented partitions (ASPs) seeks to improve low-frequency sound isolation capabilities. An ASP is a partition which has been mechanically and acoustically segmented into a number of small individually controlled modules. This paper provides a theoretical and numerical development of a single ASP module configuration, wherein each panel of the double-panel structure is independently actuated and controlled by an analog feedback controller. A numerical model is developed to estimate frequency response functions for the purpose of controller design, to understand the effects of acoustic coupling between the panels, to predict the transmission loss of the module in both passive and active states, and to demonstrate that the proposed ASP module will produce bidirectional sound isolation.

Active sound transmission control of a double-panel module using decoupled analog feedback control: Experimental results

“…The filter response for this application was designed to be a low-pass filter with a slight notch near 3 kHz. 21 The predicted and measured controller responses are shown in Fig. 7.…”

“…The magnet and voice-coil assemblies provided the actuation of the panels. The measured Thiele-Small parameters and the extracted enhanced parameters 20,21 for this driver are shown in Table I.…”

“…20,21 The control scheme eliminates the need for time-advanced reference signals while minimizing the surface velocities of both panels ͑instead of just the transmitting panel͒, thus allowing bidirectional performance. The purpose of the paper is to present the experimental module configuration, the measurement system setup, and to report the experimental results for the new module.…”

An extended lumped-element model and parameter estimation technique to predict loudspeaker responses with possible surround-dip effects

“…The authors have previously investigated active sound transmission control modules with similar properties, 8,9 but only in the context of one-dimensional sound transmission for normally incident and transmitted plane waves. True employed destructive experimental techniques and basic calculations to isolate surround and spider compliances from their compound compliance, 10 but he did not incorporate them into a model or consider associated resistances and effective surround masses.…”