A New SAE Recommended Practice for Brake Natural Frequency and Damping Measurements

As part of the development of a New SAE Recommended Practice for Brake Natural Frequency and Damping Measurements, the US Working Group on Brake NVH conducted a series of Round Robin tests and developed detailed recommendations for such measurements. The results of these tests are summarized in this paper. Initial results showed that there were difficulties with the identification of the types of modes being measured. However, when the results were carefully categorized, the measured natural frequencies agreed quite well. The measured damping coefficients showed much larger variations. In some instances, differences of more than 200% were found between testers. The steps taken to improve the consistency of results and subsequent Round Robin tests are described.