Squeak and Rattle Prediction for Robust Product Development in the automotive industry
Doctoral thesis, 2021

Squeak and rattle are nonstationary, irregular, and impulsive sounds that are audible inside the car cabin. For decades, customer complaints about squeak and rattle have been, and still are, among the top quality issues in the automotive industry. These annoying sounds are perceived as quality defect indications and burden warranty costs to the car manufacturers. Today, the quality improvements regarding the persistent type of sounds in the car, as well as the increasing popularity of electric engines, as green and quiet propulsion solutions, stress the necessity for attenuating annoying sounds like squeak and rattle more than in the past. The economical and robust solutions to this problem are to be sought in the pre-design-freeze phases of the product development and by employing design-concept-related practices. To achieve this goal, prediction and evaluation tools and methods are required to deal with the squeak and rattle quality issues upfront in the product development process.

The available tools and methods for the prediction of squeak and rattle sounds in the pre-design-freeze phases of a car development process are not yet sufficiently mature. The complexity of the squeak and rattle events, the existing knowledge gap about the mechanisms behind the squeak and rattle sounds, the lack of accurate simulation and post-processing methods, as well as the computational cost of complex simulations are some of the significant hurdles in this immaturity. This research addresses this problem by identifying a framework for the prediction of squeak and rattle sounds based on a cause-and-effect diagram. The main domains and the elements and the sub-contributors to the problem in each domain within this framework are determined through literature studies, field explorations and descriptive studies conducted on the subject. Further, improvement suggestions for the squeak and rattle evaluation and prediction methods are proposed through prescriptive studies. The applications of some of the proposed methods in the automotive industry are demonstrated and examined in industrial problems.

The outcome of this study enhances the understanding of some of the parameters engaged in the squeak and rattle generation. Simulation methods are proposed to actively involve the contributing factors studied in this work for squeak and rattle risk evaluation. To enhance the efficiency and accuracy of the risk evaluation process, methods were investigated and proposed for the system excitation efficiency, modelling accuracy and efficiency and quantification of the response in the time and frequency domains. The demonstrated simulation methods besides the improved understanding of the mechanisms behind the phenomenon can facilitate a more accurate and robust prediction of squeak and rattle risk during the pre-design-freeze stages of the car development.

structural dynamics

finite element analysis

product development

squeak and rattle

sound quality

simulation

Virtual Development Laboratory (VDL), Hörsalsvägen 7A, and online Via Zoom (for passcode to the link below or reserve a seat at VDL, contact mohsen.bayani@volvocars.com)
Opponent: Professor Mohamad Qatu, Eastern Michigan University, United States

Author

Mohsen Bayani

Chalmers, Industrial and Materials Science

Empirical characterisation of friction parameters for non-linear stick-slip simulation to predict the severity of squeak sounds

SAE International Journal of Vehicle Dynamics, Stability, and NVH,;Vol. 6(2021)

Journal article

Finite Element Model Reduction Applied to Nonlinear Impact Simulation for Squeak and Rattle Prediction

SAE International Journal of Advances and Current Practices in Mobility,;Vol. 3(2020)p. 1081-1091

Journal article

Resonance Risk and Mode Shape Management in the Frequency Domain to Prevent Squeak and Rattle

Journal of Vibration and Acoustics, Transactions of the ASME,;Vol. 144(2022)

Journal article

Squeak and rattle prevention by geometric variation management using a two-stage evolutionary optimization approach

Journal of Computing and Information Science in Engineering,;Vol. 22(2022)

Journal article

Analysis of sound characteristics to design an annoyance metric for rattle sounds in the automotive industry

International Journal of Vehicle Noise and Vibration,;Vol. 17(2021)p. 3-4

Journal article

The sound quality of a product conveys its operational quality. The customers - consciously or not - connect some quality attributes of a product to its sound quality, such as the powerfulness, robustness and durability. While some operational sounds in these products are designed to indicate their quality, the existence of unexpected irregular sounds in a product might be perceived as annoying if not a failure indicator. In passenger cars, squeak and rattle sounds are the most common annoying sounds of this type that are audible inside the car cabin.

For decades, customer complaints about squeak and rattle have been among the top sound quality issues in the automotive industry, burdening high warranty costs to the car manufacturers. Today, the quieter in-cabin environment due to improvements in the operational sound quality of the car subsystems, as well as the increasing popularity of electric engines, as green and quiet propulsion solutions, stress the necessity for attenuating annoying sounds like squeak and rattle more than in the past.

To rectify squeak and rattle problems in a robust, sustainable and economic way, it is needed to address the problems during the design stage of the car, where concept-related changes are economically justifiable.

This research investigates the development and application of methods and tools in different engaged fields to enable the detection and rectification of squeak and rattle risk during the car design stages.

Squeak and Rattle Prediction for Robust Product Development

Volvo Cars, 2016-08-01 -- .

Subject Categories

Production Engineering, Human Work Science and Ergonomics

Tribology

Applied Mechanics

Vehicle Engineering

Fluid Mechanics and Acoustics

Driving Forces

Sustainable development

Areas of Advance

Transport

Production

Materials Science

ISBN

978-91-7905-553-0

Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5020

Publisher

Chalmers

Virtual Development Laboratory (VDL), Hörsalsvägen 7A, and online Via Zoom (for passcode to the link below or reserve a seat at VDL, contact mohsen.bayani@volvocars.com)

Online

Opponent: Professor Mohamad Qatu, Eastern Michigan University, United States

More information

Latest update

11/18/2021