The Influence of Structural Mobility on Truck Interior Noise

A digital signal processing method is employed to generate mobility functions and acoustic transfer functions. The acoustic transfer function is defined as the sound pressure level per unit force at the cab mount. Peaks in the driving point mobility function) measured at the cab mount locations, correlate with peaks in the acoustic transfer function. These functions were evaluated in the frequency range 50–1000 Hz where truck interior noise is strongly influenced by structural vibration. Reducing the mobility leads to a reduction in the acoustic transfer function. A method for evaluating bracket structural changes was determined and some general design guidelines established for the reduction of truck interior noise.