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Higher demands on comfort and efficiency require a continuous improvement of the shift process. During the launch and shift process the clutch control is used to get a smooth and efficient behavior. In this short time of acting the shifting behavior can be rated. Many control concepts use a clutch characteristic to calculate the actuator signal based on the clutch torque. Therefore, a high quality of this characteristic is necessary. Because of the dynamic process during clutch engagement the clutch characteristic needs further information to reach a high accuracy for the control algorithm. In this paper an existing clutch torque characteristic is extended to a characteristic map where the clutch torque becomes a function of the current actuator signal of the clutch and the clutch slip. The extension of the torque characteristic describes the slip based dependencies, e.g. the friction coefficient.

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.

In this paper, a control approach for the active reduction of engine-induced vibrations in automotive vehicles is presented. As a controller, a discrete-time multiple input multiple output (MIMO) disturbance-observer-based state-feedback controller is designed using linear parameter-varying (LPV) gain-scheduling techniques. The use of LPV control design techniques has the advantage that the stability of the overall system is guaranteed even when the gain-scheduling parameters are changing. The control approach is validated experimentally with an active vibration control system installed in a Golf VI Variant. Two inertia-mass actuators (shakers) and two accelerometers are attached to the engine mounts. Nine frequency components are targeted in the reduction and excellent results are achieved in vehicle driving tests for constant and time-varying engine speeds.

The precision of direct fuel injection systems of combustion engines is crucial for the further reduction of emissions and fuel consumption. It is influenced by the dynamic behavior of the fuel system, in particular the injection valves and the common rail pressure. As model based control strategies for the fuel system could substantially improve the dynamic behavior, an accurate model of the common rail injection system for gasoline engines - consisting of the main components high-pressure pump, common rail and injection valves - that could be used for control design is highly desirable. Approaches for developing such a model are presented in this paper. For each key component, two models are derived, which differ in temporal resolution and number of degrees of freedom. Experimental data is used to validate and compare the models. The data was generated on a test bench specifically designed and built for this purpose.

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.