Riemann D.,HEAD Acoustics GmbH |
Haverkamp M.,Ford Motor Company
SAE Technical Papers | Year: 2011
Rust accumulated on disc rotor surfaces causes brake judder and excessive grind noise. This low frequency noise phenomenon is audible especially at low vehicle speed without masking from other noise sources like wind and road noise or power train sound. This often leads to customer complaints resulting in significant warranty costs. Alternative drive systems like hybrid or full electric power trains will emphasize this problem. Most studies concentrate on optimization of the brake system to reduce low frequency brake noise. In this work, the potential for optimization on vehicle level was investigated. The most effective NVH optimization can be achieved by improving and matching the acoustic properties of the vehicle and the brake system. In a first step, the main structure borne noise transfer paths have been identified by means of Transfer Path Analysis. A detailed analysis of the relevant transfer paths shows critical sound transmission of the suspension system and its attachments to the vehicle body. The potential of this approach for brake noise optimization is demonstrated by an example. As a second step, the radiating body surfaces contributing to the perceived brake noise have been identified using panel contribution analysis. This helps to optimize the vehicle body structure and trim package. The potential for improvements has been predicted using a modified interior noise synthesis model. The results have been verified experimentally by principal modifications to the vehicle. Copyright © 2011 SAE International.
Head Acoustics Gmbh | Date: 1994-10-05
apparatus and instruments for low-current engineering, namely for communications, high-frequency and control technology as well as the processing of acoustic signals, electrical measurement and acoustic devices, devices for analysis and diagnosis of sound and noise, devices for hearing-oriented sound field analysis, binaural analyzers, direction mixers, apparatus for the spatial mapping of complex sound fields using binaural recording Apparatus and instruments for weak-current engineering, namely for communications, high-frequency and control technology as well as the processing of acoustic signals, electrical measurement and Acoustic devices, devices for analysis and diagnosis of sound and noise, devices for hearing-oriented sound field analysis, binaural analyzers, direction mixers, apparatus for the spatial mapping of complex sound fields using binaural recording Apparatus and instruments for low-current engineering, namely for communications, high-frequency and control technology as well as the processing of acoustic signals; electrical measurement and acoustic devices; devices for analysis and diagnosis of sound and noise; devices for hearing-oriented sound field analysis; binaural analyzers; direction mixers; apparatus for the spatial mapping of complex sound fields using binaural recording.
Head Acoustics G.M.B.H. | Date: 1992-03-24
sound analyzer for analysis and diagnosis of noise and sound levels, head phones, electronic filters, audio recorders, audio playback units, signal processors for sound analysis and measurement, and binaural mixing consoles.
Agency: Cordis | Branch: FP7 | Program: CP-FP | Phase: SST.2008.1.1.3. | Award Amount: 5.11M | Year: 2010
The CITYHUSH project will support city administrations in the production and implementation of noise action plans according to the directive EC 2002/49. The identified hot spots and noise acting plans made with the existing technology suffer from major shortcomings: 1. poor correlation between hot spots with annoyance and complaints; 2. most measures lead to increased emissions; 3. only indoor noise comfort is addressed. Step change solutions are proposed to reduce noise in the city environment. The project deals with developing suitable problem identification and evaluation tools and with designing and developing solutions for hot spots, which show high correlation with annoyance and complaints. Following innovative solutions and tools will be developed: 1. Concept of Q zones (zones in inner where only quiet low emission vehicles are tolerated). 2. Concept of parks embedded in Q zones. 3. Improved noise score rating models for indoors by integrating low frequency noise and the occurrence of high noise single events. 4. Noise score rating models for the outdoors. 5. Objective and psychoacoustic evaluation tool for low noise low emission vehicles. 6. Mathematical synthesis tool for noise from low noise low emission vehicles. 7. General performance noise specifications for low noise low emission vehicles. 8. Novel concepts for low noise roads based upon dense elastic road surfaces. 9. Novel concepts for low noise roads based upon grinding of asphalt top layers. 10. Novel concepts for tyres for low noise vehicles, including heavy vehicles. 11. Criteria for use of low noise motorcycles. 12. Active and passive noise attenuation measures within the tyre hood. 13. Solutions for high low frequency absorption at facades of buildings. 14. Solutions for high low frequency isolation in the propagation pad. All the above solutions and tools will be designed, prototyped and validated. They will result in obtaining the anticipated noise impacts.
Kim S.,Hyundai Motor Company |
Park D.C.,Hyundai Motor Company |
Hong S.,Hyundai Motor Company |
Sellerbeck P.,HEAD Acoustics GmbH |
And 3 more authors.
SAE Technical Papers | Year: 2013
The sound sources of modern road vehicle can be classified into three components, driving sound (sound generated through normal driving patterns and events), operating sound (sound generated through actuated components not related to driving), and generated synthetic sound (electronic warning / interactive feedback). The characteristic features of these sounds are dependent upon customer expectation and usage requirements. Additional development complexities are introduced due to each market's cultural and regional differences. These differences in preference must be considered for the establishment of the target sound quality in the early vehicle development process. In this paper, a sound quality goal setting procedure based on user preference is introduced. The sound targets are created as a result of the user preference investigation and validated by intercultural comparison. Copyright © 2013 SAE International.