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An approach for model-based control strategy design for diesel hybrid drive-trains has been developed, permitting the reduction of fuel consumption as well as of exhaust gas emissions. The control strategy consists of four core-functions: the SOC-management, the operation mode determination, the gear selection, and the thermal monitoring. Based on those different interpretations, a control strategy can be designed that leads to great reductions in fuel consumption or alternatively to a mentionable decline of nitrous oxides. In this trade-off, both aims can not be optimized at a time. Though, the strategy to be used is a compromise, designs for control strategies are possible that reduce both for a significant amount. Extending this control strategy by adding functions for transient behavior at start-up and load changes; phlegmatization enables additional potentials for emission reduction.

The Stuttgart Driving Simulator currently under construction at the University of Stuttgart makes out the main component of the University's new automotive research platform. The facility will be one of the largest of its kind in Europe. The simulator is based on a powerful eight axes motion system to realistically recreate the linear and rotary motion as perceived by the driver during a real trip. To add further value to the driving simulator, it is designed to house a real vehicle which can be easily exchanged - from small passenger cars up to large luxury sedan vehicles as well as SUVs. To assure a sound testing environment, the driving simulator features a realistic graphical and acoustic representation of the vehicle environment such as roadway, environment, and traffic. This is achieved through a complex surround visualization system with very high level of detail as well as an advanced spatial acoustic noise generator.

In this paper it will be shown how a database containing information of the road characteristics of a frequently driven route can be automatically generated and continually updated in a vehicle during each drive. The contained information can be used as foresight information in predictive driving strategies. By using only drive train information, standard sensors (e.g. from ESC and ABS), and a GPS relevant road characteristics (curves, slopes, speed limits, etc) can be identified during the drive, stored in an on-board database, and used to optimize fuel consumption or driving comfort in subsequent trips along the route. The system is verified using a driving simulator with a 3D surround graphics system.

In this paper the situation concerning electric loads and the corresponding power electronics in passenger vehicles is described based on an analysis of an upper mid class vehicle. The large number of loads and semiconductor devices demand alternative structures to operate the loads. In this paper an alternative structure is presented, which can reduce the number of power semiconductors. This structure needs to be optimized. This paper describes the optimization methods used and presents some optimization results.

Electronic control units of engines have an ever-increasing complexity and more and more software functions need to get calibrated. Today it is possible to automate virtually every test procedure needed for these calibration tasks. But with currently available systems the effort required to set up automatic procedures often outweighs the advantages even if a commercial toolbox is readily available. The goal of this paper is to show a new concept for a calibration system that allows for creation and modification of test sequences with relatively little knowledge and reuse of test procedure components. Included is a language that features special commands and integrated knowledge for engine test bed applications. Flexible handling of exception situations, reusability of test procedure components and extensibility of the language will be discussed. The implementation of a typical test procedure will be shown.

The development of modern engine management systems makes ever-more stringent demands of the tools used. In future, the Hardware-in-the-Loop (HiL) simulation, used primarily for hardware and software tests to date, is also to be used for control function parameter adaptation tasks. This results in the need to provide highly precise, real-time-capable simulation models in all phases of the development process. This can be done by the use of modern methods for identification of non-linear, static and dynamic multi-variable systems, partly in conjunction with conventional physical model structures. In particular, artificial neural networks prove flexible in use in this case. This allows modelling dependent on the information available in the various phases of the engine development process. Thus, in the early phase, it is possible to develop engine models with computation results from complex engine simulation programs such as PROMO or GT Power.

Engine management systems in modern motor vehicles are becoming increasingly extensive and complex. The functionality of the control units which are the central components of such systems is determined by the hardware and software. They are the result of a lengthy development and production process. Road testing of control units, together with testing them on the engine test bench, is very time consuming and costly. An alternative is to test control units away from their actual environment, in a virtual context. This involves operating the control unit on a Hardware-in-the-Loop test bench. The control unit's large number of individual and interlinked functions necessitates a structured, reproducible test procedure. These tests can, however, only be conducted once an engine prototype has been completed, as the parameters for the existing conventional models are determined from the data measured on the test bench.