Skip to main content
Article thumbnail
Location of Repository

The introduction of a Sound Quality Engineering Process to Jaguar Cars : executive summary

By Gerard T. Dunne

Abstract

The control of the noise and vibration generated by an automobile is referred to as Noise, Vibration\ud and Harshness (NVH) engineering. It involves identifying the design detail required to reduce the\ud noise and vibration inside the passenger compartment of the vehicle to levels that are acceptable to\ud the customer. It also involves delivering an engine or a powertrain sound character that is both\ud pleasing to the customer and that suits the character of the vehicle. Tuning the sound generated by a\ud vehicle to deliver a particular character is referred to as Sound Quality Engineering. This document\ud summarizes the work of the EngD research programme that was aimed at developing a structured\ud process for engineering the Powertrain Sound Quality of an automobile.\ud The need for developing a Sound Quality Engineering Process at Jaguar Cars was identified\ud through a review of customer evaluations of the sound in Jaguar's vehicles and those of its\ud competitors. This review established that Jaguar's existing vehicles were trailing the leading\ud competition in terms of the delivery of Powertrain Sound Quality. The reason for this shortfall was\ud that the NVH Department at Jaguar did not have a focus on delivering the customer requirements.\ud Without this focus there was no means of using the customer level requirements,\ud for Sound Quality\ud to drive the vehicle design process. The EngD research programme resulted in the formulation and\ud implementation of a Sound Quality Engineering Process at Jaguar Cars that addressed this need.\ud The first part of the research programme involved developing a means of quantifying the\ud differences in the subjective Sound Quality character perceived by the customer. It was established\ud that the subjective nature of the Powertrain Sound Quality could be represented by two underlying\ud dimensions; a measure of the degree of Refinement and a measure of degree of Powerfulness. An\ud assessment technique was developed that enabled the subjective Sound Quality character for a\ud given vehicle to be quantified through its location within a 2-Dimensional Sound Quality Space,\ud the axes of which were defined by each of the two underlying dimensions of Sound Quality. This 2-\ud Dimensional Sound Quality Space provided the means of quantifying the differences in the Sound\ud Quality characters for all of the vehicles competing in the luxury vehicle sectors. It was applied to\ud define subjective Sound Quality targets for all of the new vehicle programmes at Jaguar Cars.\ud These targets identified the required improvements to each of the two underlying dimensions of\ud Sound Quality needed to address the shortfalls in Jaguar Cars' existing vehicles.\ud The second part of the research programme involved identifying the key acoustic features within\ud the sound signatures of Jaguar's vehicles that were responsible for determining the differences in\ud subjective perception between these vehicles and their competitors. The changes to these key\ud acoustic features were related to the required improvements to each of the two dimensions of\ud Sound Quality that were established from the subjective target setting process.\ud The final part of the research programme involved developing techniques that linked these key\ud acoustic features to the noise sources and paths that were responsible for generating them. Through\ud this link it was possible to establish the changes to these noise sources and paths that were\ud necessary to deliver the required changes to the key acoustic features. In this way the required\ud improvements to each of the two underlying dimensions of Sound Quality were used to define the\ud vehicle design specification at the concept stage of the vehicle development programme and\ud consequently drive the vehicle design process. The ability to link the subjective customer level\ud requirements for Sound Quality to the design detail specification has overcome the previously\ud identified shortfall within the NVH development process at Jaguar Cars.\ud The techniques developed during the EngD research programme were formulated into a Sound\ud Quality Engineering Process. Although the process was developed for Jaguar Cars the findings\ud from the research and the techniques developed have since been applied by the different brands\ud within the Ford Motor Company. Within Jaguar Cars the process has been implemented across all\ud of the new vehicle programmes. It has directly resulted in significantly improved Sound Quality\ud characters in the new vehicles that have been recently introduced to the luxury vehicle market

Topics: TL
OAI identifier: oai:wrap.warwick.ac.uk:3976

Suggested articles

Citations

  1. A Method for Evaluating Exhaust Sound Quality - Steady Speed Sound and Sound Varying with Acceleration',
  2. (1989). A Method for Evaluating the Interior Sound Quality of Automobiles, Unikeller Conference,
  3. A Method of Evaluating Exhaust Sound Quality',
  4. A New Approach to the Impulsiveness in the Noise of Motor Vehicles', Autotech'85, Paper C399/246,1985. Page 95 of 99 The Introduction of a Sound Quality Engineering Process to Jaguar Cars
  5. (1999). A New Tool for the Onboard Objective Assessment of Vehicle Interior Noise Quality, Society of Automotive Engineers, Paper 1999-01-1695, Traverse City, doi
  6. A Standardized Scale for the Assessment of Car Interior Sound Quality, ' Society of Automotive Engineers, doi
  7. A Study of Noise in Vehicle Passenger Compartment during Acceleration', Society of Automotive Engineers, doi
  8. (1998). Aurally Adequate Evaluation of Sounds',
  9. (2000). Combining Methods to Evaluate Sound Quality I,
  10. Development of Vehicle Sound Quality - Targets and Methods, Society of Automotive Engineers, doi
  11. Effects of Power Plant Vibration on Sound Quality in the Passenger Compartment During Acceleration', Society of Automotive Engineers, doi
  12. Emotional Effect of Car Interior Sounds: Pleasantness and Power and Their Relation to Acoustic Key Features', Society of Automotive Engineers, doi
  13. (2002). EngD Submission - Personal Profile', The University of Warwick,
  14. (2002). EngD Submission - Published Papers & Presentations',
  15. (2002). EngD Submission - Sound Quality Brand Engineering',
  16. (2002). EngD Submission - Sound Quality Engineering Process, Implementation & Measures of Success',
  17. (2002). EngD Submission - Understanding the Sounds & Objective Sound Quality Target Setting', The University of Warwick,
  18. (1999). EngD Subrnission - Sub ective Sound Quality Target Setting', The University Y of Warwick,
  19. Engine Sound Quality Evaluation Using Semantic Differential Method',
  20. (1999). Evaluating Vehicle Interior Noise Quality Under Transient Driving Conditions', Society of Automotive Engineers, Paper 1999-01-1683, Traverse City, doi
  21. Evaluation Method of Engine Sound Quality for Compact Sedan with 4 Cylinder Engine During Acceleration', doi
  22. Evaluation of Vehicle Sounds through Synthesized Sounds that Respond to Driving Operation',
  23. Examples of Successful Sound Designs for Sports Cars and SUV Applications',
  24. Facts and Models, doi
  25. Improving Interior Noise Produced During Acceleration', Society of Automotive Engineers, doi
  26. Inprovement of Sound Quality of Vehicle Noise',
  27. Introduction to Factor Analysis - What it is and how to do it, doi
  28. Noise, Vibration and Harshness for the Customer's Point of View',
  29. Practical Applications of Sound Quality Analysis Techniques',
  30. Quantification of Subjective Unpleasantness Using Roughness Level', Society of Automotive Engineers, doi
  31. Research on Sound Quality Evaluation Methods of Exhaust Noise',
  32. Sound Quality Estimation of Car Interior Engine Noise at Steady Revolution', doi
  33. Sound Quality Evaluation of Exhaust Note During Acceleration', doi
  34. Sound Quality Evaluation of Interior Noise -Objective Evaluation of Comfortableness and Powerfulness',
  35. Sound Quality Evaluation of Passenger Vehicle Interior Noise', Society of Automotive Engineers, doi
  36. Statistical Evaluation of an Annoyance Index for Engine Noise Recordings', Society of Automotive Engineers, doi
  37. Study on Exterior Idling Sound Quality Evaluation Method for Diesel Engine Trucks', doi
  38. (2000). The Development of a 'Sports' Tailpipe Noise with Predictions of its Effects on Interior Vehicle Sound Quality',
  39. The Effect of Powertrain Sound on Perceived Vehicle Performance', doi
  40. (1988). The Method of Paired Comparisons, doi
  41. (1989). The Oxford English Dictionary, 2d Edition, doi
  42. The Subjective Response of Occupants to the Noise Inside Vehicles',
  43. Towards and Objective Estiarnte of the Subjective Reaction to Diesel Noise',

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.