This paper describes as an advanced technology on noise and vibration, the method of predicting vibrations in a complete motorcycle, and ananlyzing the acoustic radiation from the solid surface of the parts.
The vibrations of a complete motorcycle are predicted by using the Finite Element Method (FEM) and the Building Block Approach (BBA). Practically sufficiently accurate connector and damping characteristics necessary for the analysis have been obtained by using experimental data base. Moreover, it was possible to find out, from the distribution of strain energy, the locations for effective measures.
In the analysis of the sound radiation from the solid surface of the parts, acoustic analysis has been made by putting the measured data of the surface velocity of the parts into the Boundary Element Method (BEM). Acoustic power and the surface sound pressure distribution by parts can be obtained by quantitative evaluation and grasping the sound source in detail. Besides, effective guidelines are obtained for reducing noise through the analysis of amplitude acoustic sensitivity.
These analytical technologies are effective for shortening the development period, reducing the weight of the component parts and determining an optimum specification for reducing noise and vibration.