How can simulations help us with the development of complex systems?

Digitization undoubtedly brings many advantages – but it also presents us with new challenges. Combined simulations at various levels, from the overall system to the component, are used to provide answers to what-if questions including many variables that influence each other. This type of question is, for example, common in the transportation sector. What happens if driving on public traffic routes suddenly costs money? Or what happens to traffic if downtown areas are closed to cars? How do assistive systems influence traffic flows? Co-simulations run through varying scenarios and evaluate them to facilitate improved system understanding. They are an important tool for the ensuring of system characteristics.

Such simulation systems are also helpful in the energy sector, where the so-called "energy revolution" is resulting new structures and requirements. Our energy is increasingly being provided by small, decentralized producers who are replacing large power plants as key energy suppliers. What was formerly an information-poor energy supply system is becoming a de-centralized, highly complex system, within the scope of which information is exchanged dynamically. The establishment and integration of the ICT infrastructure needed for this purpose requires the use of development methods that both meet requirements regarding the complexity and dynamics of the future energy supply system and are also faster and cheaper than conventional field tests.

This is made possible by complex simulation systems that run multiple simulations simultaneously at different levels. These co-simulations are used to carry out virtual analysis of the interaction between a larger number of  components and architectures within one dynamic overall system.

Multiple simulators that each observe the corresponding differing details of degree and highly diverse systems are linked together. A self-driving car is already a highly complex microsystem that becomes even more complex when competing interests and goals on the macro-level of the roadway system meet and must be weighed against each other. In such cases simulations must be carried out on multiple levels to identify how traffic flow can be optimized in such a way that objectives which, in some cases, are opposed can cooperate with each other. Individual interests such as faster transportation from A to B must be balanced against general rules and goals such as safety, environmental protection, and traffic flow. Parallel to this, systems should be designed in such a way that individual personal freedoms are preserved to the greatest extent possible.

Complex co-simulation models can signifi cantly shorten the product development process and identify problematic issues relating to the interaction of many functions and components at an early stage. The Multi-Scale Multi-Rate Simulation competence cluster carries out virtual testing of prototypes; optimizes and validates design processes; and examines model creation for descriptive research. Over and above this, co-simulation itself is a research focus.