## 5 Application of Sys-IMF for Decision Support in Modular Product Family Design
### Phase II: Evolution of Economical Impacts for Alternative Modular Concepts  
In the second phase, the alternative product architecture concepts are evaluated with respect to the filtered effects from the knowledge base and compared with each other. For this purpose, the calculation bases from Table 2 are used to determine the values for the respective concept alternatives. Since the effects of modularity exhibit a time-dependent behavior, the savings and expenditures in the example are laid out over a period of 3 years. This ensures that the long-term effects are also taken into account in the assessment [61; 62; 63; 64; 65]. The temporal determination is also of particular relevance for the determination of the saved process costs, since the numbers of repetitions are time-dependent. In addition, this also allows the timing of the ROI to be determined. The calculated results for the KPIs of the selected economic target values are shown in Table 3 for the three concepts. For confidentiality reasons, only the difference to the reference product architecture is shown, and the respective direction is color-coded. In the development phase (ID 1 xxx), significant savings can be achieved with all three concepts due to the reduced number of variants. For example, the development times for administration (1210) and variant generation (1160) are drastically reduced, especially in concepts 2 and 3, which in turn have a direct impact on the variety-induced complexity costs. The initial development costs (1230) for the conceptual design, engineering and implementation of the respective alternatives have a negative impact here, but must be taken into account for the overall calculation. Considering the benefits from the development alone would make this calculation a negative business case, but seen across the entire value chain, it is not. In the present use case, the main advantages arise in the procurement phase (ID 2 xxx). Here, procurement costs (2010) can be significantly reduced, which can be attributed to the economies of scale resulting from higher quantities due to standardization measures. As already shown in the filtered IMF in Figure 13, the proportionally largest savings for all concepts result here. Concept 3 in particular can generate the greatest cost benefits. However, the process flexibility (2050) additionally increases significantly due to the variant reduction. Here, the higher quantities enable a change in procurement strategy and an increase in make-or-buy flexibility. In the production phase (ID 3 xxx), significant advantages are also achieved through the modular concepts. In particular, the saving of development time means that planning can start earlier (3000), and thus the overall lead time becomes more predictable and shorter. Contrary to the knowledge-based prediction from the filtered IMF, the investment costs for the tools (3130) increase for all three concepts. This is due to the fact that the new components also require new tools (in this case, new casting tools), which must first be procured. In the long run, however, fewer tools are needed, so that in the overall picture this positively affects the ongoing production costs. In addition to the process costs saved, there are also other advantages in production that cannot be quantified directly but must nevertheless be taken into account. Thus, all three concepts enable increased automation of production processes (3120), which can lead to further follow-up effects during implementation. Modularization is hence an enabler in the sense of the domino effect for further savings. In Sales and Marketing (ID 4 xxx), process time savings result from faster quotation generation (4000)--especially due to the predefined configuration logic. Additional potential can be tapped here in the future with the help of a configurator. However, the design of the configurator requires additional initial efforts that are not included in the model. This calculation shall be supplemented as necessary.