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Autonomous driving was and is one of the most important research and innovation drivers in the automotive and supplier industry. In addition to the predicted energy savings, a reduction in the number of accidents and their level of damage is also expected. In particular, the functional testing and legislation of highly automated driving functions play a decisive key role here. This results in a justified need for innovation and research and means major challenges for the entire technology sector. Traditional methods such as real-world tests and X-in-the-loop tests for proving functional safety still have their justification, but cannot answer all the questions posed by the diverse requirements in daily use. In particular, urban environments with highly complex traffic scenarios and diverse groups of actors can only be mapped to a limited extent using existing methods.

In this work, a novel approach for testing automated vehicle systems in urban environments is presented. The goal is to create a safe and valid environment in which the vehicle under test can interact with real road users under realistic conditions. The basis is a highly realistic virtual model of a German city center. The physical behavior of the vehicle and the pedestrian is measured and transferred to the virtual city model in real time. Sensor models enable the interaction of the vehicle with the virtual environment and the pedestrian. With the help of different studies with different focuses, both individual functionalities as well as the overall functionality are finally evaluated.

Driven by the need for automation and autonomy as well as the need to reduce resources and emissions, the automotive industry is currently undergoing a major transformation. Technologically, this transformation is addressing a wide range of challenges and opportunities. The optimal control of all components is significant for the sustainable development and eco-friendly operation of vehicles. Additionally, robust control of the actuators forms the basis for the development of driver assistance systems and functions for autonomous driving. The actuators of the steering system are particularly important, as they enable safe and comfortable lateral vehicle control. Therefore, the model-based development and virtual simulation of an innovative highly robust control approach for modern Steer-by-Wire systems were conducted in this thesis. The approaches and algorithms described in this thesis allow the design of robust Steer-by-Wire systems and offer the opportunity to conduct many investigations in a computer-aided virtual environment at an early stage in the development process. This reduces time- and cost-intensive testing on prototypes, avoids unnecessary iterations in the design and significantly increases the efficiency and quality of the development. The desired high degree of robustness of the steering control also ensures that the parameterization of the steering feel generator can be freely selected for the individual application. This enables safe and comfortable vehicle lateral control.In summary, the research results described in this thesis accelerate the development of new, modern Steer-by-Wire systems whose robust design forms the basis for the realization of functions for highly automated and autonomous driving.

The automotive industry is experiencing a significant transformation driven by the demand for automation, autonomy and resource reduction. A key factor in this transformation is the model-based design and validation of advanced vehicle systems, particularly Steer-by-Wire systems, which are essential for highly automated and autonomous vehicles. However, Steer-by-Wire systems, characterized by the absence of a mechanical connection between the steering wheel and the front wheels, present unique challenges for achieving robust control as well as ensuring driving comfort and safety. This dissertation addresses these challenges by exploring innovative approaches for the optimal control of Steer-by-Wire systems, highlighting the model-based design and the integration of simulation environments. For this, a detailed model is developed, considering all relevant degrees of freedom and nonlinear characteristics of a real Steer-by-Wire system. Based on this detailed model, the dissertation presents a novel multivariable control approach that enhances the robustness and performance of Steer-by-Wire systems compared to traditional designs. The derived control approach demonstrates improved system stability and performance, effectively addressing parameter uncertainties and varying driving conditions. These satisfactory characteristics are validated both in an augmented simulation environment and on a real prototype. By combining virtual testing within the augmented simulation environment with real-world prototyping, the need for labor-intensive physical testing is minimized, thus optimizing development resources and time. The presented methods are not only employed for the development of Steer-by-Wire systems, but also for further applications in automotive engineering, including driver assistance systems, sensor evaluations and perception systems. In conclusion, the research contributes to mechatronics and automotive engineering by advancing autonomous driving through robust control approaches, virtual testing and agile development strategies. The insights and methodologies proposed not only advance the development of novel Steer-by-Wire systems, but can also serve as a basis for future innovations in mechatronic systems that require precise control and reliability.