Acoustic Imaging EndofLine Inspection for Annoying Noises Valerie

Acoustic Imaging End-of-Line Inspection for Annoying Noises Valerie Cook and Ahad Ali IEOM Dubai March 3 -5, 2015 Low Frequency, close to reflective surface, front of vehicle ABSTRACT: Control of annoying noises such as buzzes, squeak and rattles (BSRs) is important to the perception of quality in complex manufactured products such as automobiles. The objective of this research is to develop and validate a concept for objectively identifying annoying noises inside vehicle cabins using spherical beamforming technology. This study provides information the behavior of the concept system under ideal conditions. This data will serve as a baseline for the continuing research into the effects of the manufacturing environment on the system performance. The methodology resulting from this international collaborative project will provide a new means of inspecting acoustic characteristics of finished products with greater speed, precision and accuracy - resulting in higher quality manufactured products. APPROACH: • Design & build fixture for providing known sound source locations inside the vehicle cabin. Use CATIA to locate potential sources relative to beamformer. • Identify uncontrollable factors expected to affect localization accuracy under ideal conditions (DOE). • Test vehicle under ideal conditions (hemi-anechoic chamber, no vibration input, controlled environment) • Select method to identify main lobe vector output from beamformer. • Analyze localization error data. Modeling Theta Error Microphone Array of Beanformer in test vehicle Modeling Phi Error Sample Defect Report of BSR in Vehicle Cabin Research Findings • Patented unique manufacturing inspection methodology for annoying noises (May 2009 Patent Application filed; May 2008 Provisional Patent Application filed) • Extensive analysis of measurement uncertainty of spherical beamformers used as manufacturing inspection gauges, not currently available. Current Process for Control of Acoustic Quality in Automobiles Concept Process using a Beamformer with end-of-line shaker inspection