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Today diesel engines are controlled by electronic control units (ECU's), performing complex functions. New developed control algorithms should already be tested under real-time conditions in the laboratory before they are applied to the real engine. Hardware-in-the-loop simulation (HIL) is a powerful tool for development and test of the control algorithms implemented in the ECU's. Modern diesel ECU's are able to react to rotary oscillations of the crankshaft within a work cycle in order to control idling and running smoothness by a cylinder-individual variation of the start of delivery and the injection time. As a consequence also the simulator has to be able to generate torque oscillations with a resolution adapted to the sample rate of the ECU. The paper describes a high resolution real-time model which was designed by expanding a steady state model by a parallel thermodynamic model with a simplified structure.

Advanced automatic transmissions are controlled by electronic control units (ECUs) which perform the gear change and furthermore a lot of complex control and diagnostic functions. Hardware-in-the-loop simulation (HIL) is a powerful tool to develop and test the control algorithms implemented in the ECUs. The simulation is based upon mathematical models of the different power train components, adapted to the real-time requirements. In this paper an improved real-time model of an automatic transmission with a Ravigneaux planetary gear train is presented. This transmission contains among other components numerous clutches and brakes. The time-variant states of these nonlinear elements (sliding and static friction) lead to numerical problems with respect to real-time simulation. In the suggested model the transferred torques of the different clutches and brakes are calculated using the methods of multi-variable control.

Advanced passenger car control is based on multiple electronic control units (ECUs), performing complex control algorithms and diagnostic functions for the different power train components like combustion engine, automatic transmission, brakes or chassis. For research and development the engineers need tools to test and verify either the reliability of new control strategies implemented in the ECUs or the interaction of different ECUs in a car. These tests should be done to the highest extent in the laboratory to reduce costs and risks which are involved in test stands or experimental cars. Therefore the optimal solution is the operation of the ECUs in a real-time closed loop environment.