Technology that makes it possible to operate multiple virtual machines on a single hardware platform without impacting the controllers’ real-time core is the basis for new edge server systems. This article was originally published in the Automation 2021: Control Systems Ebook.
Most of us will have encountered a product that was processed using a ProCom cutting control system at least once in our lives. It controls the cutting of the majority of foams produced worldwide, which are used in mattresses and furniture or in airplane and car seats. It is also responsible for numerous fabric cutting applications—regardless of whether it is a high-quality branded suit, discount jeans or a massproduced T-shirt. This position has been achieved by the CNC control and software provider since 1983 by specializing in cutting processes. The company started with foam contour cutting. The clothing market with textile cutting followed. With additional control and software solutions for plasma jet, water jet, and laser beam cutting, the company has become an expert in industrial cutting.
The company serves different cutting technologies with the industrial PC-based CNC300. The ProCom customers are mainly machine builders. Intelligent algorithms that have been developed over decades ensure an efficient cutting process and provide optimal parts nesting on the cutting machine. This guarantees maximum material utilization and high-precision cutting results. It is a particularly complex challenge, especially when it comes to 3-D foam contour cutting.
When cutting foam contours, a wide variety of contours is cut from a large block of foam with a rotating band knife, without switching the knife off and on again between the individual cutting jobs or removing it from the block. All parts to be manufactured are cut in a single work step. When it comes to the paths between the parts, it must also be considered that the parts that have already been cut do not come into contact with the band knife again and are damaged as a result. The software that users can use to optimize these cutting processes runs on the machine control hardware and can also be configured there as required. In some cases, it is also run at a CAM workstation for work preparation and then transferred to the control system, including detailed production planning for the respective day.
Focus on plasma, water, and laser beam cutters ProCom supplies the motion control, including the graphical user interface (GUI) for machine operation with tool selection and all other machine-related functions. It is precisely this concept that has convinced machine builders in the foam and textile industries worldwide. ProCom also offers this approach to machine builders in the plasma, water, and laser cutting segments. The industrial end user is offered software that is tailored to the machine and achieves the best possible productivity. The efficient operation combined with a high level of flexibility thanks to a wide range of functions with adjustable parameters is particularly impressive.
The company has recently developed a new solution platform for laser cutting especially for the Asian and the Chinese market. Studies show that around 50% of the forecast growth in APAC will be achieved in laser cutting. Falling production costs make laser cutting the technology of the future in many areas. A not insignificant market for ProCom is the steel market. Numerous machines for sheet metal cutting from Europe are a successful example. Whether decorative object or industrial sheet metal, with the complete package from ProCom, the best possible material efficiency is achieved in all applications. The complete package just fits.
How the motion control system became an edge server
Since a complete package consists of more than just a CNC controller, today, ProCom’s control solutions are based on hypervisor technology to distribute the individual tasks among dedicated virtual machines (Figure 1). However, this was not the case in the past. In earlier projects, the company implemented a control system with a dedicated CNC and PLC core and an industrial PC-based hardware platform and software as a human-machine interface (HMI). At the time, a hardware-based three-processor solution served as platform and architecture. The HMI was initially based on DOS, then OS/2 for a while, before switching to Windows and the various Windows generations.
Today, it is based on Windows 10 IoT Enterprise. Then and now, the On Time RTOS-32 real-time operating system coordinates the cutting movement of the servo axes, the integrated programmable logic controller (PLC) functionality and all safety monitoring functions needed for CNC machine control. Communication between the two discrete processors was based on the multiprocessor message exchange (MMX) protocol.
Ongoing protocol changes
For many years, ProCom controllers were not fieldbus-based. Instead, the servo axes were connected via the common ±10 Volt setpoint interface, which also handled the evaluation of the encoder signals including zero-pulse processing, which ProCom controls enabled as standard. With the advent of fieldbuses, the company took advantage of the fiber-optic-based digital Sercos I and later Sercos II interfaces in the mid-1990s. In 2011, a further development step was taken with the design of Ethernet-based communications. ProCom chose EtherCAT for the real-time capable protocol, having purchased the master stack. It was during this development phase that the company decided to move from a multiprocessor system with a dedicated card for the real-time processor, to a multicore-based x86 solution with one to two cores dedicated to the Windows world plus one core each to the PLC and CNC motion control functions. To implement this step, the hardware-based multiprocessor solution, which at the time had been in use for almost 30 years, needed to be virtualized on a multicore processor.
At this point, ProCom was faced with the essential question: “Make or buy?” A virtualization solution was required that separates the Windows world for GUI and work preparation functions from the real-time functions without affecting them. As part of research, the company came across Real-Time Systems, analyzed and tested the product intensively, and ultimately decided not to get involved in developing a hypervisor itself. The real-time hypervisor was fully developed, covered all the required functions, and had already sufficiently proven itself on the market. Since then, it has been in use on the ProCom controls. The real-time hypervisor also copes with significantly more complex tasks that have been added due to the requirements of Industry 4.0 and digitalization.
Task complexity continues to rise
Today, the ProCom system, which is scalable in performance via Intel Core processors, has an OPC-UA interface for communication with higher-level control systems that control larger system networks, or to transfer operating and machine data to manufacturing execution system (MES) and enterprise resource planning (ERP) connections. In addition, the company also offers its own.
Industry 4.0 platform called Clouver, which offers numerous dashboards and tools for monitoring, management and maintenance of the machines and for which every ProCom controller on the market already has a suitable interface. For Clouver to receive all relevant data, it is necessary to be able to access the real-time platform (Figure 2). This is another point where the hypervisor plays an essential role as data must be collected in the real-time machine during the cutting process and then made available to the other stakeholders via the Windows world without interfering with the real-time processes. The need to handle all these tasks has turned the controller into a multifunctional system that resembles an edge computer as it is comprehensively networked both horizontally and vertically in all directions. As porting it toward a real-time-capable fog server would also be easy, the hardware could undergo further consolidation in the future.
The right virtualization decision ProCom is extremely happy with its decision to buy the real-time hypervisor from RTS. Tasks have not become any easier in the past decade, and the motto to stick to one’s core competencies has clearly worked for them. “We feel in good hands with Real-Time Systems,” said Harald Müller, head of consulting and production at ProCom (Figure 3). “Our collaboration is always constructive. RTS are true experts with deep know-how and great products. The support works, the solution works, and our team that integrates the bought-in modules into our software solution has had absolutely no problems. And everything to do with regular services and updates is well organized.”
Intuitive tool for workload consolidation
As a software solution that…
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