Linux systems offer many advantages
Since the mid-1990s, PC systems have been increasingly used in the automation of production machines. In addition to networking and control, its usage particularly includes the operation of the machines via an HMI / SCADA system. The selection of the operating system such as Real-time RTOS (for controllers), Windows or Linux usually depends on the purpose.
One of the most serious disadvantages of the widespread Windows operating system is the consumption of resources and the so-called TCO (total cost of ownership), since Windows systems require a complex x86 architecture. Inspired by the development of smartphones with powerful, multi-core ARM processors, Linux operating systems are getting more and more into focus when the digitization of production processes and machines is sought and is definitely the best choice! The use of Linux can drastically reduce system costs compared to PC-based systems!
Linux is available in various distributions for both x86 and many ARM systems and covers a wide range of applications. Especially for visualization and HMI / SCADA solutions, Linux systems represent an ideal platform. The HMI / SCADA Toolbox WebIQ from Smart HMI, is i.g. predestined for the use under Linux. It consists of a server component (WebIQ Connect) and the HMI client running in an HTML5 browser.
The server is the backend of the HMI / SCADA system and provides, preferably via an OPC-UA connection, the data interface (process data gateway) to the controllers for continuous recording of process data (historical data), alarms and events. The data is stored in a local SQLite database and thanks to the open architecture can also be read and processed by other programs and databases via the SQLite driver.
The WebIQ Server (WebIQ Connect) can be operated on almost all Linux systems. Especially for small applications or embedded applications, it’s possible to base the installation on inexpensive ARM systems such as Raspberry Pi or Beaglebone Black. The compact structure of the C++ coded server in conjunction with the event-based architecture ensures sufficient performance and low resource consumption even on such micro-systems.
For demanding applications of e.g. tens of thousands of data points per second, WebIQ can also use Linux to run on a powerful x86 platform
The actual visualization of the data (HMI) takes place via an HTML5-compatible browser, which is part of the common Linux distributions. In this case, attention must be paid to integrated graphics acceleration in order to obtain a smooth operation even on smaller systems. Thanks to the rapid development in the smartphone market processors like SoC (ARM Cortex-A, Rockchip, etc.) are available as dual- or even quad-core processors at a low cost.
WebIQ and Linux together contain all components for a machine visualization and form a highly scalable solution for a wide range of applications of HMI / SCADA solutions. Another advantage: Non-HTML experts can also create easily Web HMIs and web apps by using WebIQ. This makes it easy to start web-based visualization under Linux.