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An improved model-based two-degree of freedom control system for the intake manifold pressure in passenger car diesel engines is described in this paper. The aim of this control system is to track the air charge setpoint rapidly and precisely. To achieve this, an inverse model of the intake manifold dynamics is included in the feedforward control path. The system parameters which are necessary to calculate the inverse model are setpoints from other control loops in the gas system. These generated setpoint values allow for decoupling of the individual control loops in the gas system as far as possible. The parallel linear feedback controller is designed to further improve the accuracy of the control system. The calculated feedforward control signal and the feedback control variable additively generate the effective opened area of the intake throttle valve.

For control of most automatic transmissions with wet clutches (e.g. dual clutch transmission), it is important to know the kiss point with high accuracy. The kiss point describes the value of the control variable for which the friction clutch begins to transmit torque. Another significant value during the filling process of a wet clutch is the takeoff point. This is the hydraulic pressure which causes the clutch piston to begin to move. This paper presents an innovative approach that enables the joint determination of the kiss point as well as the takeoff point in only one identification procedure. In contrast to existing methods, this method is able to identify both points without the necessity for undesired auxiliary system excitation. Therefore it is possible to reduce wear on system components such as synchronization rings. The method presented in this paper analyzes the measured filling pressure characteristic over time as the system response to a defined excitation.