New Method Uses Single Accelerometer to Analyze Rolling Tire Vibrations
A study from Virginia Tech introduces a technique that uses a single wireless accelerometer inside a tire cavity, combined with two optical sensors, to perform Operational Modal Analysis of rolling tires. The method exploits the non-integer ratio between tire and drum diameters to synthesize a virtual array of sensors from a single test run, overcoming limitations of current laser-based approaches. The advance could make tire noise characterization significantly cheaper and more practical, including for treaded tires and real-road conditions.
Researchers have proposed a new Operational Modal Analysis (OMA) methodology for characterizing the dynamics of rolling tires, which are a major contributor to low-frequency structure-borne vehicle noise in the 0–500 Hz range. The current standard approach relies on Laser Doppler Vibrometers (LDV), which are expensive, time-consuming, and largely restricted to smooth tires in controlled laboratory settings due to optical speckle problems on treaded surfaces. The new method uses a single wireless Tire Cavity Accelerometer (TCA) and two optical sensors to timestamp both cleat impacts on a test drum and the accelerometer's circumferential position on the tire. By leveraging the non-integer diameter ratio between the tire and drum, vibration responses across multiple revolutions are clustered by sensor position, effectively creating a virtual sensor array around the tire circumference from a single test run. Signal conditioning via order tracking removes periodic noise from contact patch deformation, and two modal identification algorithms—Frequency Domain Decomposition (FDD) and Covariance-based Stochastic Subspace Identification (SSI-Cov)—were applied, with SSI-Cov successfully identifying 11 circumferential modes up to 240 Hz. The authors argue the approach is more cost-effective, efficient, and adaptable than LDV-based methods, with potential for on-road testing applications.
What's missing
The study is based on a 2020 master's thesis and has not yet undergone formal peer review. Key open questions include how the method performs across different tire types, speeds, and road surfaces beyond the controlled drum test rig, and whether the virtual array assumption holds under variable real-world operating conditions. Quantitative comparison of modal identification accuracy against LDV ground-truth measurements is not detailed in the abstract.
What different sources said
- arXiv physicsCenter
Virtual-Array Operational Modal Analysis of Rolling Tires Using a Single Tire Cavity Accelerometer
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