## 4 Implementation of the BBSM Concept in the Virtual Environment
### Design of the BBSM Virtual Environment
Due to the limitations of the experiment (i.e., the limited number of participants and limited duration), a closed system was observed; therefore, adding new manufacturing resources to the system (i.e., emergence of new manufacturing companies) was not possible. Instead, we focused on optimization in terms of upgrading the available manufacturing resources. Table 3 presents examples of how service exchange can upgrade the capabilities of the consuming companies in the case of 3D printing manufacturing. Companies specialized in mechanical engineering provide better equipment in terms of computer hardware (e.g., improved cooling and ergonomics results in faster program development) and hardware for manufacturing (e.g., lighter moving parts and more rigid structure result in faster manufacturing of PCB components). Companies specializing in electrical engineering provide upgrades in terms of electrical components that can enhance either manufacturing processes (e.g., better motion control that results in faster 3D printing) or computational hardware (e.g., improved electronic components that increase the speed of computing). Companies specializing in IT engineering provide upgrades in terms of software, which can either improve the manufacturing process (e.g., 3D printing tool path optimization that results in faster 3D printing), or engineering software (e.g., improved simulation software that results in faster PCB manufacturing). **Cooperation:** The complex necessities of manufacturing make it challenging for enterprises to execute all production processes independently in order to offer a product service system. Therefore, a substantial number of enterprises collaborate closely to augment manufacturing capabilities [55]. By purchasing the other two types of services, the players in the game upgrade their APU, thereby reducing the time required to perform a service (i.e., increased frequency). The APUs are codependent on each other to upgrade themselves, meaning that there is a closed system in the game in which funds and services are exchanged only between players. Upgrading the APU follows a predefined production function that determines how the time to perform a service changes with the number of upgrades. The production function defines the highest possible limit on output that a company can obtain with a certain combination of production factors (inputs) at a given state of technical knowledge during the production period [56]. In the game, the production function defines how the capacity of service provision changes when the state of the production system changes. The production factor is only the state of manufacturing equipment or the capital invested in equipment; no other factors are observed. Thus, when there is enough capital invested in the production system, the ability to offer a service (i.e., the frequency of service) changes. In the case of the presented implementation, the service provider of the mechanical engineering type (e.g., 3D printing) upgrades its manufacturing system in accordance with the production function by purchasing the services of the other two types. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{1}{c}{**ConsumerProvider Mechanical**} & **Electrical** & **IT** \\ \hline \multirow{4}{*}{**Mechanical**} & \multirow{4}{*}{\(\backslash\)} & Upgrade of & Upgrade of \\  & & 3D printer control & 3D printer \\  & & system capabilities & software and \\  & & & firmware \\ \hline \multirow{4}{*}{**Electrical**} & Upgrade of & & Upgrade of \\  & PCB manufacturing & \(\backslash\) & electrical design and \\  & capabilities & & simulation software \\ \hline \multirow{4}{*}{**IT**} & Upgrade of & Upgrade of & \\  & computational & computational & \\ \cline{1-1}  & hardware & hardware (electrical) & \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Examples of service exchange between three types of companies in the case of 3D printing.