Dag M. Brück

Realtime Simulation of Detailed Vehicle and Powertrain Dynamics

This paper describes typical modeling and real-time simulation issues that occur in automotive applications. Real-time simulations of detailed Modelica benchmark models for chassis and powertrain are presented. They demonstrate the powerful real-time capabilities of Dymola and the Modelica modeling language. One of the benchmark models for vehicle dynamics is a detailed model with 72 degrees-of-freedom with bushings in both the front and rear wheel suspensions. It was simulated in real-time with a sample rate of 1 kHz on the RT-LAB environment from OPAL-RT using a Pentium 4, 3066 MHz processor. This is made possible by Dymola’s unique and elaborate symbolic processing of the model equations.

Feasibility of Detailed Vehicle Modeling

A feasibility study is presented concerning detailed vehicle modeling, including submodels for engine, transmission mechanics and hydraulics, as well as three-dimensional chassis behavior. The study was conducted jointly by Ford Motor Company, Dynasim AB and DLR. The results demonstrate that complex behavioral models of each subsystem can be developed, used and validated independently from each other, and finally assembled together to an overall model. Therefore, this approach could be the basis to establish modeling standards that allow collaboration between model developers throughout the automotive industry.