Welcome to the PLCopen® electronic newsletter.
- PLCopen celebrates its 30th anniversary – new videos on our YouTube channel
- PLCopen Application Examples for Motion Control into OOP released
- PLCopen Motion Control – new certification
- PLCopen training certification
The PLC has changed. In its 50 years of existence, it changed from a big, clumsy heavy rack sized unit (however modular and rugged) to small flexible and low-cost devices, that despite their smaller format have of course a lot more performance. It has changed from strict logic to the combination of logic, motion, and safety, both in the development environment as in the controller. And, on top of that, the ever more important communication and exchange.
And the software has changed: from a couple of rungs of ladder diagram, to a massive number of different functionalities linked together with structuring tools, different programming languages and an ever-increasing libraries of function blocks.
The PLC has changed from a stand-alone unit to a key part of an automation solution. It has moved into the drives, in embedded controllers, in trucks, in farming equipment, and a lot of other places beyond the classical industrial automation. The PLC is more alive than ever, and it is here to stay!
It is very clear that in the future we will be even more dependent on software. And this software will be in more and more application areas, with possible new areas that we are not aware of now. Who would have imagined the impact of the smart phone in its 15 years of existence? Or of Google in its 20 years of existence? Or of Amazon or Facebook? Or even of a software driven car like Tesla makes them?
With the growth of the capabilities and functionalities in the IT domain at such a high pace, the impact on industrial automation is imminent. How will it look? Certain initiatives like Industry 4.0, Industrial IoT, and Made in China 2025 already show clearly that the role of software will become even more prominent, or even at the core of the new business models that will arise. Communication is key, but also a key target for sabotaging actions, so the security, and aligned safety gets to the forefront. New ways of communication make new architectures possible, creating new business opportunities that were not possible before. We have to think about new flexible solutions providing new business models, new ways of serving the market and new ways of production.
PLCopen will continue to support these trends with its focus on global harmonization. The PLCopen organization offers a solid base, now and in the future, for harmonizing principle technological challenges and a platform for members to work on these.
We hope you will enjoy watching the PLCopen’s anniversary videos on our YouTube channel.
With the PLCopen specification “Function blocks for Motion Control”, the PLCopen Task Force Motion Control provided a set of standardized Function Blocks to ease modularization and reuse of motion control software.
We now released the document “Application Examples for Motion Control – Porting Function blocks for motion control into OOP”, version 1.0.
This new document presents an object-oriented implementation of the motion control specification, which can be combined with the set of procedural standard Function Blocks (FBs). The general design of the proposed object-oriented (OO) implementation is a single Axis Class implementing different functions as Methods instead of formerly used multiple FBs. A benefit of the proposed software design is the compatibility with procedural motion control FBs: the standard FBs can call the Axis Class internally to combine both approaches in one application. Thus, the user of the OO implementation needs not to be familiar with the detailed OO principles or language elements for using it.
As common in object-oriented programming (OOP), an interface is used to define the motion standard since it describes how a class is presented to the outside (sometimes including the behavior). More precisely, an interface is the definition of the functionalities that a class may implement. The class is the actual implementation of the defined functionalities, including vendor-specific aspects.
Correspondingly, this document standardizes a motion interface. For using this standard, an axis class needs to be implemented, which follows (“implements”) this standardized motion interface. In short: the interface defines the functionalities, but not how they are implemented (their content), which is done vendor-specific in an axis class.
Utilizing three application examples, this document shows how the standardized FBs from the PLCopen motion control specification can be ported to OOP by using a standardized interface itfAxis. To apply the standard in a vendor-specific implementation, the programmer develops a class, which implements the interfaces itfAxis and, thus, has all the functions standardized in itfAxis without implementation. Then the actual, vendor-specific implementation of these functions is programmed.
The advantage of the proposed interface itfAxis is that one can decide how to program: on one hand, the standard FBs can be used, and they can internally call the itfAxis methods. On the other hand, it is possible to program in OOP by using the defined methods to start a new command, get the current status of an axis, and update or abort a command.
The details on the proposed interface and the contained methods as well as several user-defined data types are introduced in the document.
This document focuses on the motion control part of the axes only. In real projects, the axis class will have many other properties and methods for communication, hardware configuration, and additional aspects. For simplicity, these are not explained in this document.
The new document can be downloaded from the PLCopen website.
We are glad to announce that one of our members has been awarded the PLCopen Motion Control certificate:
Kingstar with their product KINGSTAR version 4.3 (for PLCopen Motion Control part 4)
This brings the total number of certified companies to 28 and of certified products to 69.
For more information, please check our website www.PLCopen.org.
The University of Poitiers in France renewed their training certifications for the courses
- "Systèmes automatisés" for IEC 6113103 programming, and
- "Motion Control" for PLCopen applications
For more information on the certified training centres please check our website www.PLCopen.org.
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