New Method Uses Single Accelerometer to Analyze Rolling Tire Vibrations
Researchers developed a novel technique using a single wireless accelerometer inside a tire cavity combined with optical sensors to characterize tire vibrations during rolling motion. The method creates a virtual sensor array by clustering vibration data from multiple tire revolutions based on the accelerometer's position, overcoming limitations of traditional laser-based approaches. This advancement could improve vehicle noise reduction and tire design while being more practical for testing treaded tires in realistic conditions.
A new operational modal analysis (OMA) technique addresses long-standing challenges in measuring rolling tire dynamics, which contribute significantly to low-frequency structure-borne noise in vehicles (0-500 Hz). Traditional methods using Laser Doppler Vibrometers are complex, time-consuming, and ineffective on treaded tires due to speckle formation issues. The proposed approach uses a single wireless Tire Cavity Accelerometer (TCA) paired with optical sensors that timestamp cleat impacts and accelerometer position. By exploiting the non-integer diameter ratio between the tire and drum in a test rig, the researchers synthesize responses from multiple virtual sensors distributed around the tire circumference using data from a single test run. After applying order tracking to remove periodic contact patch deformation signals, the team used Covariance-based Stochastic Subspace Identification (SSI-Cov) to identify 11 circumferential modes up to 240 Hz. The method is more efficient and cost-effective than existing approaches and is adaptable for on-road testing.
What's missing
The study does not discuss validation against independent measurement methods, comparison of results with previous tire modal analysis studies, or quantitative assessment of measurement uncertainty and repeatability across multiple test runs.
What different sources said
- arXiv physicsCenter
Virtual-Array Operational Modal Analysis of Rolling Tires Using a Single Tire Cavity Accelerometer
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