Test Technique and Objective Rating Method To Quantify Automotive Brake Rattle

During vehicle development, NVH engineers often have a difficult time when faced with brake rattle issues. Resolving these issues becomes more challenging when vehicles are not available for evaluation, test schedules are short and subjective ratings are inconsistent. In part, the reason brake rattle issues are so difficult to resolve is the absence of a standard test and evaluation procedure. This paper will present an innovative technique to perform brake rattle screening on a laboratory shaker without the need of a vehicle corner or detailed road profile data. Additionally, an objective rating method will be discussed that will provide a more accurate and consistent method of grading results when comparing the rattle intensities of multiple test configurations and ultimately will allow the engineer to predict customer satisfaction levels. This objective rating technique is also applicable for identifying rattle patterns and quantifying intensity during vehicle evaluations.

In addition to introducing the test technique and a detailed procedure for the collection and processing of data, several applications cases will be discussed. These cases are described to provide the reader a better insight on the process that was used in developing this test methodology.