Door Closure Sound Quality Engineering Process 2019-01-1523
An important factor contributing to a customer’s subjective perception of a vehicle, particularly at the point-of-purchase, is the sound created by the passenger doors during closure events. Although these sounds are very short in duration the key systems that control the sounds produced can be highly coupled. Similarly, the necessary efforts required to understand key design criteria affecting the sound can also be highly complex.
Within this paper sub-systems affecting the door closure sound are evaluated to understand key structural properties and behaviors toward the contribution to the overall sound produced. This begins with the subjective preferences of typical sounds and the difficulties with both measuring and reproducing these sounds appropriately and leads directly to the target setting and target cascading process. With targets in place, it becomes important to link them with physical measurements of the vehicle and door system to identify the key controlling mechanisms that can be affected through design.
The behavior of the door system during a closure event is key for the sound produced and can be studied to understand both the nearfield acoustic field generated as well as the structural vibration patterns. This can be accomplished during a closure event and linked to in-lab assessments that allow for greater repeatability and flexibility. Boundary conditions for the door structure are also relevant to the sound produced, including the transmission of forces into the seals, latch and striker, and bump-stops, as well as understanding the effects from the vehicle interior cavity.
Once the key controlling mechanisms affecting the door closure sound quality are understood, it allows for the sound produced to be shaped as desired. This can be accomplished by leveraging analytical modeling efforts, supplemented with necessary test data, to design key components and systems to achieve the desired sound.
Todd Freeman, Bret Engels
Bruel & Kjaer North America Inc., Brüel & Kjaer Sound And Vibration A/S
Noise and Vibration Conference & Exhibition