Research on a Noise Control Device : 3rd Report, The Fundamental Design of the Device (2)

An active noise control device called active noise absorber or ANA, which is based upon damped, resonant filters is developed and demonstrated. It is similar to structural positive position feedback (PPF) control, with two exceptions: (1) Acoustic transducers (microphone and speaker) cannot be truly collocated, and (2) the acoustic actuator (loudspeaker) has significant dynamics. The speaker dynamics can affect performance and stability and must be compensated. While acoustic modal control approaches are typically not sought, there are a number of applications where controlling a few room modes is adequate. A model of a duct with speakers at each end is developed and used to demonstrate the control method, including the impact of the speaker dynamics. An all-pass filter is used to provide phase compensation and improve controller performance and permits the control of nonminimum phase plants. A companion experimental study validated the simulation results and demonstrated nearly 8 dB of control in the first duct mode. A multi-modal control example was also demonstrated producing an average of 3 dB of control in the first four duct modes.

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Active Helmholtz Resonator With Positive Real Impedance

Journal of Vibration and Acoustics ◽

10.1115/1.2345678 ◽

2006 ◽

Vol 129 (1) ◽

pp. 94-100 ◽

Cited By ~ 5

Author(s):

Jing Yuan

Keyword(s):

Noise Control ◽

Helmholtz Resonator ◽

Control Device ◽

Positive Real ◽

Noise Field ◽

Strictly Positive Real ◽

Control Devices ◽

Passive Noise ◽

Active Resonator ◽

Electronic Resonance

The impedance of a passive noise control device is strictly positive real, if the device is installed in noise fields with weak mean flows. Passive noise control devices are, therefore, more reliable than active ones. Active control may be applied to a Helmholtz resonator to introduce electronic resonance. It will affect the impedance Zact of the resonator. A controller may be designed such that (a) Zact is small and resistive at some tunable frequencies; and (b) Re{Zact}⩾0 in the entire frequency range of interest. If criterion (a) is satisfied, the active resonator can suppress duct noise at tunable frequencies. It is difficult to design a controller to satisfy criterion (b) because parameters of the controller depend on acoustic parameters of the noise field. A new method is proposed here to design an active controller to meet both criteria simultaneously. The satisfaction of criterion (b) implies a positive real Zact and a robust active resonator with respect to parameter variation in the noise field. Experimental results are presented to verify the performance of the active resonator.

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S&N-S Light: An anthropic noise control device to reduce the noise level in densely occupied spaces encouraging personal control of voice

The Journal of the Acoustical Society of America ◽

10.1121/1.4987934 ◽

2017 ◽

Vol 141 (5) ◽

pp. 3663-3663 ◽

Cited By ~ 1

Author(s):

Sonja Di Blasio ◽

Giulia Calosso ◽

Giuseppina E. Puglisi ◽

Giuseppe Vannelli ◽

Simone Corbellini ◽

...

Keyword(s):

Noise Level ◽

Noise Control ◽

Personal Control ◽

Control Device

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Active Noise Control Using Phase-Compensated, Damped Resonant Filters

Noise Control and Acoustics ◽

10.1115/imece2003-41831 ◽

2003 ◽

Cited By ~ 1

Author(s):

Jesse B. Bisnette ◽

Jeffrey S. Vipperman ◽

Daniel D. Budny

Keyword(s):

Noise Control ◽

Control Method ◽

Active Noise Control ◽

Control Device ◽

Pass Filter ◽

Acoustic Transducers ◽

Active Noise ◽

Controller Performance ◽

The Impact ◽

Resonant Filters

An active noise control device called active noise absorber (ANA), which is based upon damped, resonant filters is developed and demonstrated. It is similar to structural positive position feedback (PPF) control, with two exceptions: 1) acoustic transducers (microphone and speaker) can not be truly colocated, and 2) the acoustic actuator (loudspeaker) has significant dynamics. The speaker dynamics can affect performance and stability and must be compensated. While acoustic modal control approaches are typically not sought, there are a number of applications where controlling a few room modes is adequate. A model of a duct with speakers at each end is developed and used to demonstrate the control method, including the impact of the speaker dynamics. An all-pass filter is used to provide phase compensation and improve controller performance. A companion experimental study validated the simulation result and demonstrated nearly 10 dB of control in the first duct mode.

Download Full-text