Technical Library: Recent Project Summaries
Axle Noise Investigation
A Tier 1 supplier of rear axles was experiencing an axle whine issue that required potential hardware changes to improve performance. Sound Answers provided testing and analysis support including vehicle level data collection, dynamometer testing, operational deflection shape measurements and modal analysis to identify key contributors to the axle whine. A bending mode of the rear axle was identified as the key contributor and specific component level modifications were recommended to the manufacturer for problem resolution.
Automatic Shifter Noise Evaluation
Sound Answers provided support to a manufacturer of automotive automatic shifter assemblies to evaluate the NVH performance of design alternatives based on an OEM test specification. Acoustic data was collected in an anechoic chamber and analyzed using Bruel & Kjaer Sound Quality software and Excel statistical analysis tools. Objective data showed the design alternatives caused no degradation in NVH performance to the component specification and the manufacurer was able to adopt this cost reduction.
Axle Balance Machine Performance Investigation
An automotive OEM provider of rear axles utilized Sound Answers to determine if new axle balance machines compared to previously installed equipment. Vehicle-level data was collected and single plane balance algorithms were used to calculate residual imbalance from parts off both the original equipment and the new balancers. Based on the results, the OEM provider did not accept delivery of the new balancer machines until they could adequately meet the current standard.
Biopsy Device Sound Evaluation
A medical device manufacturer required improvement in the noise performance of biopsy devices. Sound Answers collected acoustic data in a quiet room for competitive devices and utilized sound quality metrics and jury evaluation to determine the noise characteristics that aligned with perceived quality. After a design review, the Customer was able to address the most critical design attributes and gained the ability to evaluate further design changes for optimal sound performance.
An RV industry suspension system provider was in need of technical NVH support to resolve an audible moan issue. Sound Answers performed vehicle testing using order analysis and sound quality tools to reveal a critical system resonance and clarification that the powertrain, not the suspension, was the source of the noise. Customer resources were then focused on the true source of the moan issue, and quarantined vehicles were improved and shipped.
Driveline Noise and Vibration Training
A Tier 1 automotive supplier required an intensive 2 week training course to improve their NVH capabilities. Sound Answers provided a tailored course including NVH fundamentals, instrumentation, spectral analysis, rotating machinery, modal analysis, and operational deflection shapes in a lecture and hands-on environment. Engineers left the course with an understanding of NVH principles for their application, resulting in improved testing and analysis techniques and stronger interpretation of internal data reports.
Corporate and Competitive Tractor Noise Evaluation
An agricultural tractor manufacturer requested a comparison of competitive tractors to determine their NVH performance relative to the current market. Sound Answers provided measurements utilizing sound quality metrics and ISO standards for whole-body and hand-arm vibration for each tractor over a range of operating conditions. The OEM received a knowledge of product performance in the current market, and recommendations to improve the NVH performance of their tractors.