Abstract: Generalized force transmissibility (GFT) and sum of GFT integrals of power-train mounts are defined, which are appropriate to be taken as vibration isolation index of power-train mounting system. A design optimization approach for power-train mounting system is proposed, with many design variables, several constraints of rigid-body modal frequencies and an objective of minimizing the sum of GFT integrals. As an example, a power-train mounting system of a coach is optimized with the approach, and important design parameters, such as coordinates, angles and spring rates of power-train mounts, are optimized. As a result, the GFTs, the frequency ratio and dynamic force transmissibility are improved, thus certifying feasibility and effectiveness of this optimizatioin approach.

Key words: Generalized force transmissibility, Mounting system, Optimal design, Power-train, Vibration isolation