From Off-Line to Real Time Simulations by Model Reduction and Modular Vehicle Modelling

Over the last couple of years there has been a growing tendency in the automotive industry to use more active control systems with mechatronic components, realized by electronic control units (ECU). As the ECU is a highly complex system and also for reasons of safety and costs the ECU-test is not carried out in road tests, but at a much earlier time, i.e. in the laboratory, using Hardware-in-the-Loop (HiL) simulation. This requires real-time environmental models. This paper shows how the transition from offline multi-body-system (MBS) models to real-time simulation can be achieved automatically by using a component oriented reduction procedure for vehicle suspensions, which keeps the full component parameterization. This necessitates a transformation of the equations of motion from differential algebraic equations (DAE) into ordinary differential equations (ODE). For use in HiL-simulators the equations of motion with open interfaces of the applied forces and torques are provided to be integrated in a modular dynamic ride model.Copyright © 2003 by ASME