Focus is on novel system architecture generation of complex systems (e.g., powertrains, machinery equipment, high tech systems, etc.) using platform-based design ontology that allows reusability of components and facilitates co-design of active dynamical systems (e.g., powertrain and its control) is defined as a ‘top-down’ and ‘bottom-up’ design process, where new optimized system platforms are generated ‘in the middle’ of this process. The system functional and performance requirements in the specification space are mapped by (i) formalization to (e.g., architectural, spatial, etc.) constraints and objectives in the constraint space. Thereby, this process of ‘mapping’ from top-to-down can be interpreted as moving from a higher level of abstraction to a lower level. The building of system topologies satisfying the derived composition rules in the synthesis space as step (ii) and the modelling of the inherently static and dynamic properties of the corresponding system components at the constraint space as step (iii) is seen as the bottom-up process. The selected components incorporate specific physical properties and behavior that are modelled in an integrated manner, which enable co-design for active dynamic systems. Finally, new optimized system architectures (forming a system platform) are created in step (iv) and can be used for more detailed concept design evaluation in a next design phase, or are exported to following (higher or lower) system levels as ‘parametrized architectural components’ in a different platform space. Example (here): components forming an electric powertrain system layout towards electric vehicles connected to a grid (architecture) of energy users, producers.