## 2 State of the Art
### Siemens Simatic Robot Integrator  
Now, a variety of robots from several manufacturers (Figure 1) can be employed, and also various programming methods (Figure 2). Different ways to use the operating and learning interface for each of these robots can be employed in practice. Figure 2 illustrates two different types of programming languages specific to ABB and Fanuc that do the same thing. The comparison between the two programming languages proves that although they are totally different, interfaces like the SRI can read, process, and make them eligible for each other. As a consequence, virtual commissioning requires high levels of implementation functionalities. A manufacturer presented a software solution named the Simatic Robot Integrator (SRI), which allows the operation of several robots in terms of programming [11] and operating interfaces such as teach-in points and accessible jogging modes of industrial robots. To eliminate the problems induced by multiple programming languages, as well as various data management strategies and control modes, the proposed software solution provides a unified interface. Within this interface, users can choose from a range of industrial robot libraries for their programming needs. Kuka, Staubli, Universal Robots, Kawasaki, and Comau libraries can be employed in the software interface. The main options and menus of the graphical interface are Move, Position List, Power, Move Path,  
Figure 1: Application that contains robots from several suppliers. Figure 2: Robot program in different robot languages. Teach Path, Robot Messages (mainly alarms and warnings), and Configuration. Universal communication between the industrial robot and the PLC is allowed by unifying the interface (Figure 3) between the Simatic S7-1500 and the robot controller. Siemens is the world's largest producer of PLCs, with the largest number of PLC units sold [12]. For VC, Siemens has the complex PLM platform Process Simulate that can be integrated with the TIA Portal and even Mechatronics Concept Designer (MCD) with TIAP, for the development of VC applications. On the other hand, the TIA Portal is currently recognized by all robotics application integrators as the best-performing work environment for VC. However, there is no solution for the direct compatibility of the ABB RS platform with the Siemens TIA platform. To expand the use of the PLCs of its own production, Siemens has developed a new work environment, the SRI platform, for which it managed to ensure the compatibility of some PROPRIETARY software products of other robot manufacturing companies such as KUKA, Motoman, Staubli, and so on. While robots from manufacturers like KUKA and Kawasaki work in collaboration with Siemens, major producers such as ABB and Fanuc have not reached an agreement to standardize the interface within the Siemens SRI. In the following section, ABB's solution for virtual commissioning simulation, specifically RobotStudio will be discussed. [PERSON] et al. in 2022 [11] introduced tools enabling communication between two widely used software in the automation industry, RobotStudio (RS) and TwinCat (TC). These tools facilitate signal exchange between PLCs and other devices, emulating real-world system interactions. The tools have proven to be high-performance with a stable and dependable connection. A key benefit is that both PLC and robot programs can be simultaneously verified and optimized before being deployed in the physical system. Changes at the code level can be tested across the entire system in a unified environment, without the need to simplify or idealize component behavior. Based on these results, research attempts can be focused on improving the application's performance, aiming to develop a more efficient communication code to reduce latency. The authors conclude that since RS and TC are proprietary solutions limited to vendor-specific devices, the approach could be replicated using other commercial platforms or expanded to general-purpose platforms that simulate products from multiple vendors.