Joint project SNiMoRed

Multidisciplinary simulation, nonlinear model reduction and proactive control for vehicle dynamics

Within the publicly funded project SNiMoRed five mathematical institutes and two companies, set within the automotive industry, join their efforts to identify new and improved mathematical solution procedures for the effective inclusion of the key dynamic properties occurring through individual highly nonlinear components (such as elastomer and hydraulic bushings, vehicle tires) into:

  • overall vehicle simulation
  • fatigue analysis
  • controller designs
Vehicle front axle with detailed representation of hydromount
© Audi AG
Vehicle front axle with detailed representation of hydromount

Dynamic analyses of vehicles are utilized in developing complex nonlinear multi body systems with multi-disciplinary model components. The usual practice in the approximation of highly nonlinear model components such as vehicle tires, rubber and hydro bushings is insufficient for the simulation of high-frequency dynamic effects, which are essential for comfort and durability.

 

Simplified Models

A more detailed modeling leads to nonlinear partial differential equations, but because of their complexity they can't be incorporated directly into the vehicle simulation. In the project therefore nonlinear model reduction methods (such as proper orthogonal decomposition, POD) are investigated such that the vehicles main dynamic properties including the nonlinear system components are captured through simplified models with much less degrees of freedom.

For hydraulic bushings with electrorheological fluids that allow active control of its characteristics, the component models should also be refined itself. In the multidisciplinary model the interaction between elastomer and electrorheological fluid is taken into account and incorporated into the model reduction technique.

Such new and improved models in simulation open possibilities for active suspension controls, by using information about future road conditions via navigation systems or preview sensors.

Partner

  • Audi AG
  • Fraunhofer ITWM
  • John Deere Werke Mannheim
  • Julius-Maximilians-Universität Würzburg
  • Martin-Luther-Universität Halle-Wittenberg
  • TU Kaiserslautern
FE model of a tire with rim
© ITWM
FE model of a tire with rim