Adaptive Intelligent Ventilation Noise Control

To address the NASA need for quiet on-orbit crew quarters (CQ), Physical Optics Corporation (POC) proposes to develop a new Adaptive Intelligent Ventilation Noise Control (AIVNC) system to reduce acoustic noise inside the CQ and work spaces. AIVNC is based on a new multimodal, skin-like active noise controller that will be easy to retrofit and will not interfere with air flow or generate secondary noise. AIVNC cancels ventilation noise by producing high fidelity, broadband counter-acoustic energy by means of very thin, flat multifrequency active patches under the control of an intelligent adapting module (IAM) based on a spontaneous adapting acoustic model. In Phase I POC demonstrated AIVNC with in-duct streamlined MAPs based on two piezoelectric materials, reproducing high-quality sound at up to 90 dB from 300 to 10000 Hz with very low distortion; a compact driving MAP amplifier; two IAM algorithms predicting ventilation noise one step ahead to cancel it, reducing noise by up to 27 dB rms with real ISS ventilation noise provided by NASA. In Phase II POC will advance/optimize AIVNC components to build a fully functional AIVNC prototype to reduce CQ noise by >30 dB, satisfying NC 40 requirements for NASA crew quarters.