The complex nature of tires requires very precise test data to model the structure accurately. The highly damped
characteristics, geometric features and operational conditions of tires cause various testing difficulties that affect the
reliability of the modal testing. One of the biggest challenges of tire testing is exciting the whole tire at once.
Conventionally, impact hammers, shakers, and cleats are used as an excitation input. The shortcomings of these
excitation methods are the directional and force inconsistency of hammer impacts, coupled dynamics of shakers and
speed limitations of cleat excitation. Other challenges of modal testing of tires are the effect of added mass due to sensor
placements and difficulty of vibration measurement of a rotating tire with accelerometers. In order to remedy these
problems, we conduct experimental modal analysis (EMA) using a non-contact measurement technique and piezoelectric
excitation. For non-contact measurement, a 3-D scanning laser doppler vibrometer (SLDV) is used. For the piezoelectric
excitation, Micro Fiber Composite (MFC) patches are used due to their flexible nature and power capacity. This
excitation method can also be crucial to the excitation of rotating tires since the cleat excitation is not adequate for low-speed
measurements. Furthermore, the piezoelectric actuation could be used as sensors as well as noise controllers in
operating conditions. For this work, we run experiments for a loaded tire in non-rotating condition. Experiments are
carried out for the frequency bandwidth up to 500Hz to capture the structural behavior under high-frequency excitations
and its potential coupled behavior to airborne noise.
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