# PROSIM in the Cloud: Remote Automation Training Platform with Virtualized Infrastructure
## 2 State of the Art
Deployment is envisioned through a client-server architecture where the server runs the prespecified models and multiple clients can connect to it and visualize, operate and parametrize the simulation. The key role of OPC communication for linking up sensors, controllers and instrumentations is further emphasized by [9]. Several use cases with dual applicability in both R&D and educational activities are described for automation of energy systems, networked industrial laboratory and educational hardware-in-the-loop platforms. Standardized communication buses enable integration between various field equipment and controllers through software implementation of the OPC server agents using dedicated environments such as WinCC flexible or NI OPC. Wider availability of OPC clients is observed in both Matlab and LabVIEW Datalogging and Supervisory Control modules. A key idea of the study is the reusable nature of the laboratory architecture with various technologies and for various practical applications that replicate and extend existing hardware platforms for learning and experimentation. In [10], the PLC is defined as a key smart service provider for Industry 4.0 production systems for supporting smart industrial control services (SICS). New concepts that emphasize the importance for automation and PLC training in the context of capacity building for higher education are detailed in [11]. A conceptual benchmark system is presented which integrates Eaton-Moeller software and hardware with suitable input-output modules and devices on a single physical board. The goal is to facilitate teaching of ladder diagram, function block diagram and GRAFCET diagrams. In this case, the system requires extension modules in order to be able to realistically simulate industry processes beyond the learning of the PLC program development tasks. A semivirtual simulation training platform based on PLC hardware is presented by [12]. The authors describe the connection of a previous-generation Siemens S7-200 PLC system via a serial RS232 to a host system HMI for enabling intuitive training. Several simulation applications have been developed and documented, including the program design, i/o list and external wiring diagram for traffic light control, knowledge competition and a material car. It is concluded that such a solution increases the student interest in the content taught and mitigates the limitations due to available hardware stands for process models in the laboratory. An educational perspective of using such automation simulators in online teaching is discussed in [13]. The training set-up includes a virtual Siemens S7-1200 PLC and TIA Portal software which is connected to a Factory I/O virtual environment for modelling the industrial processes from a mechatronics perspective. The authors emphasize the importance of detailed study guides and step-by-step instructions to support the students and trainees during remote teaching. An important observation is to focus on building associations between the rich graphical simulations and the expected behavior of the real physical system with added complexity and uncertainty. As an alternative, a low-cost solution that enables remote access to existing laboratory systems is discussed along with practical insights in [14]. The key elements that assure continuity of PLC training include a scheduling system, remote desktop access, a graphical user interface and a microcontroller board. The PLC unit controls two physical experiments in this case, a conveyor system and a sorting machine. Visual feedback of the functionality and validation of correct operation and/or malfunctions is collected through a webcam. The developed Arduino-based interface conveys the GUI commands from the student to actions on the physical platforms, which are also interfaced to the PLC. In such way remote operation of the plant simulation is achieved.