Abstract
The transfer of vibration energy from the tire/road contact into a vehicle is done via air-borne and structure-bore noise. In this paper both paths are considered. The transfer of the tire/road noise into the vehicle through the air was discussed first. For that idea a special microphone arrangement was used to measure the noise in the near field of the tire (input) and the response with a microphone at the headrest of the front seat inside the vehicle. The resulting transfer functions for excitation at two temperatures are discussed.
Normally for estimating vibration transfer functions forces at an input point and vibration at a response point must be combined which is not possible when measuring at a rotating tire up to now. Using a laser vibrometer is also not successful, as the reflecting light from the tire requires very broadband signal analysis. So as a first estimate the vibration transfer function of a standing tire was extracted from measurements by eliminating all other influences (suspension, chassis, etc.). A new method for measuring the contact patch to spindle vibration transfer function of the loaded tire alone was applied, which consists of a combination of different approaches and the use of the electric circuit equality.