Browse Publications Technical Papers 2009-01-2091
2009-05-19

Noise Path Analysis Process Evaluation of Automotive Shock Absorber Transient Noise 2009-01-2091

Shock absorber transient noise, often referred to as “chuckle” or “loose lumber”, has been a vehicle level noise and vibration concern for many years. The noise often occurs with lightly damped shock tuning under small road inputs at low speed. This transient type noise is of particular concern to the operator because it can sound like mechanical looseness in the chassis.
This noise concern is generally addressed late in the design cycle and the options of a fix are limited to a change in damper tuning or added mass. A need for a wider design envelope exists to address this concern which must include noise paths into the structure and body sensitivity.
The study documented in this paper walks through the process of acquiring this noise on the road and reproducing it in the lab on a 4-post hydraulic test rig. The noise path analysis process is then evaluated in detail for this transient type of noise to compare the results of acquiring the NPA data as a fully disconnected suspension, fully connected suspension and a reduced 3-point shock attachment. The study then evaluates the fully disconnected suspension method for a square matrix compared to an over-defined matrix. Finally a comparison of frequency versus time domain noise path analysis is performed.

SAE MOBILUS

Subscribers can view annotate, and download all of SAE's content. Learn More »

Access SAE MOBILUS »

Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.
We also recommend:
TECHNICAL PAPER

Development of a Luxury Vehicle Acoustic Package using SEA Full Vehicle Model

2003-01-1554

View Details

TECHNICAL PAPER

A Novel Approach for Brake Squeal Control Using Shunted Piezoceramics

2006-01-3198

View Details

TECHNICAL PAPER

A Systematic Approach to Preparing Drive Files for Squeak and Rattle Evaluations of Subsystems or Components

2007-01-2269

View Details

X