Rubber Bushing Model for Vehicle Dynamics Performance Development that Considers Amplitude and Frequency Dependency 2015-01-1579

In many cars, ride is less comfortable on smooth roads. This is because when the hysteresis in the suspension components rises steeply, the increase of the equivalent spring constant at small amplitude deteriorates the vibration isolation of the suspension. Therefore suspension components should be designed to prevent a steep rises in hysteresis. Investigating the influence of hysteresis, component models, which can reproduce such hysteresis characteristics, should be installed with model parameters in the vehicle model. Using conventional methods, these parameters can be accurately identified if measurement data is provided; however, it is difficult at the earlier phase of vehicle development. Then, if conflicting performances, such as ride and handling, are to be improved, both should be considered concurrently as early in a phase of vehicle development as possible and the design specifications for suspension components should be determined to satisfy both performances. The simulations including ‘Multi-Body Simulation’ (MBS) should be performed using the same model with the same parameters. Furthermore, they should be done even if measurement data is not available. However, there is no appropriate model for the rubber bushing meeting these demands. Therefore this paper proposes a rubber bushing model and the parameter calculation method that can be used for investigating the vehicle dynamics performances in the early phases of vehicle development accurately and efficiently and specifying the dynamic characteristics of the rubber bushing.