## 3 Results and Discussion
### Proposition of a Method of Developing Immersive Metaverses for Industrial Training
#### 3.2.5 Immersive Metaverse  
The next section presents how to transform the project into an immersive metaverse, bringing a way to create a multiuser environment where it is possible to communicate through voice, interact, and create a virtual avatar. In terms of the connection system, it is necessary to choose a connection system for the environment to become multiuser, consequently transforming it into a metaverse. For the example to be developed, Epic Online Services (EOS) was chosen, free multiplatform services created to facilitate the launch, operation, and scalability of gamified applications in an easier and faster way [37]. The Advanced Framework development team also developed the EOSLink tool, which will be used as the basis and is demonstrated in Figure 11.  
EOSLink works in conjunction with the Advanced Framework to connect to EOS and enable solutions that require multiplayer in a simple way [38]. The tool connects to the Advanced Framework through the AFUEGNLink developed code. While Epic Online Services provides a wide variety of multiplayer features, the EOSLink tool does not implement these features to streamline the multiplayer experience in just two clicks, all from within virtual reality or on a desktop or mobile environment such as a cell phone. Since it will be necessary for users to log in and create their avatars in the metaverse, we created the entire interface of the project using Figma software. Screens were created so that the user can choose his or her name, host an online session, and connect to other online sessions, as shown in Figure 12.  
Figure 11: Presentation of the Advanced Framework [38]. Figure 12: User interface of the metaverse. It is necessary to export the interface screens created for the game engine. It is possible to export in common formats such as jpg and png. After importing, it is necessary to work with the image within the Unreal Motion Graphics (UMG) UI Designer, which is a visual UI tool that can create UI elements such as menus and other user interfaces [39] (Figure 13). The Blueprints visual scripting language is used to program all menu interactions after the appropriate interfaces have been developed, making it feasible to host or join an online session. The literature review indicated that is relevant to have a voice system in a multiuser application. Including this will add another layer of immersion, as well as facilitate communication between players [40]. The communication service provider for online games, Vivox platform, will be used for a multiuser voice system [41]. Vivox was chosen for its low cost, ease of applying the platform to UE4 software projects, spatial (3D) sound, and support for the Advanced Framework in conjunction with EOSLink [38]. Figure 14 shows that the entire Vivox connection was programmed through Blueprints. Concerning the interactivity and avatar system, for maximum immersion it is relevant to add interactions to the application. It is crucial to analyze the purpose of immersive metaverse development to develop the necessary interactions for its application, such as interactions with industrial equipment or virtual simulations. As the 3D modeling becomes ready, some components provided by the Advanced Framework will be used to add these interactions. The Drag component and the Select  
Figure 14: Programming the Vivox voice system. Figure 13: UE4 UI creation tool. component are two tools provided by the AF that facilitate the programming of object interaction. The Drag component allows the programming of a 3D model to have a movement relative to other 3D models through sliders, buttons, or other complex shapes [38], as Figure 15 illustrates. The Select component allows transfer of information to other objects in a quick and easy way, as explained in Figure 16.  
Combining these two elements allows simulation of an industrial training utilizing a hydraulic press that is modeled, such as two-hand control training.