Analysis And Robust Optimization Of Automobile Powertrain Mounting System

Automotive vibration and noise level has always been an important index ofperformance, with the progress of the society and the increase of people life level, the ridecomfort of automobile more and more get the attention, the vibration of the automotive hasbecome the focus of attention. Automotive vibration noise sources are more extensive, andits main source is the vibration of the powertrain, and this noise is passed to the car bodyby the powertrain mount system, so matching the right powertrain mount system to theautomotive is helpful to reduce powertrain heritability of car body, to reduce the vibrationof the automotive, to improve the NVH of automotive.In the paper, the author focuses on a car’s powertrain mount system. First of all, amulti-body dynamics model is established according to the CAD model and the parametersof powertrain by the manufacturer. And through the experimental modal analysis in the realautomotive powertrain mount system the multi-body dynamics model is verified andcorrected, finally obtained the certain precision multi-body dynamic model of powertrainmount system. By using Vibration module of multi-body dynamics software ADAMSmulti-body dynamics analysis, and get to six order natural frequency and thecorresponding energy decoupling rate of powertrain mount system. The powertrain mountsystem energy decoupling rate is low according to the experience of the engineering, andneed to be optimized. And based on the analysis using ISIGHT software aiming at energydecoupling of powertrain mount parameters respectively to multi-objective and robustoptimization, and get the stiffness of mounting. Then respectively to stiffness valuesobtained by certainty optimization and robustness optimization monte carlo analysis, getthe probability distribution of energy decoupling rate of two optimization and contrast theenergy decoupling of two optimization and energy decoupling ratio compares theprobability distribution. Finally put the stiffness of mounting by robustness optimizationinto the mount bracket model, to check the strength of the mount bracket.