Abstract
This paper describes a reciprocal method that has been developed for
measuring the transfer characteristics of vehicle body vibration and noise induced by a forced
displacement input to the tires. This method uses the principle of structural or structural-acoustical
reciprocity to determine the transfer characteristics by measuring the constraint
force produced at the tire contact patch under a condition where the vehicle body is excited
from the conventional evaluation point. Experiments were conducted in which this method
was used to measure the vibration transfer characteristics when the vehicle body was excited
by a shaker from the evaluation point. Experiments were also conducted in which this method
was used to measure the noise transfer characteristics when the body was excited from a
speaker positioned at the evaluation point in the cabin. As a result of measuring the vibration
and noise transfer functions of test passenger cars with this method, it was shown that this
technique has advantages not afforded by the conventional experimental method using a large
shaker. One such advantage is that it facilitates efficient measurement of the distribution of
the transfer functions at the tire contact patch.
Keywords - Measurement, noise, vibration, transfer function, reciprocity