Automation is no longer restricted to the conventional ways of building machines using customized controllers or Programmable logic controllers (PLC). With the rise of Industrial Internet of Things and Industry 4.0, machine builders look at providing additional features to their customers with respect to connectivity and performance. Apart from performance and features they also look at reducing overall system costs. It is a challenge for machine builders to provide connectivity to the MES and ERP layers and at the same time provide a real time, deterministic connectivity to the field devices.
Conventional vs Innovative
In a conventional approach machine builders used a customized controller or a PLC for achieving performances on the field and solving the application needs of the machine and process. A PC based solution is used to acquire data from these controllers so as to send it to the process layers or the MES and ERP layers. These PCs most of the times also host other automation related acquisition software’s. Customers are thus continuously raising their demands for achieving higher productivity, accuracy, precision, productivity, throughput coupled with a cost effective solution. Thus the biggest dilemma for any machine builder is to achieve features and flexibility requested by the customer keeping the machine costs very low.
To overcome this many machine builders choose to use PC based automation with different proprietary software to achieve the performance needed on the field layer. As the software’s for data acquisition are based on Windows the machine builders have to run a dual operating system and install these software’s. Thus the machine builders address this issue by using PC based systems and reducing the number of components in their system but they do not achieve the flexibility and cost requirements.
Flexibility and cost the core
We all use mobile phones and we as users pick and choose the make of the handset, the operating system it works on, and eventually the software’s i.e. apps which we would like to install on it. Just imagine in the automation world if the machine builders had such flexibility, wouldn’t it provide him an extra degree of flexibility? It could help him to choose the real time operating system, the network, the software to use? This eventually will help him reduce his system costs and give him the technological edge over his competitors. This is not a concept but a practical approach being used by machine builders with a PC based automation and having in-house R&D for developing software’s for their machines. Android in the mobile market has gained momentum with its open source approach. Similarly in industrial automation open source systems are catching the eye of the OEMs as well as machine builders. The usage of open source systems in automation is creating a whole new dimension of flexibilities, features, and possibilities.
Myths and misconceptions of open source
There are many myths and misconceptions about open source. Vendors provide software’s and charge machine builders for licenses or provide object codes for their software or ask the machine builder to purchase custom made hardware like ASICs and justify they are still open source. What open source truly means is there are no charges; no copyrights and users have access to the complete source code. This is when the platform is truly recognized as open source.
Open source software and applications are definitely free of cost but are also governed by different licenses. Some licenses allow the modification of the code but ask the user to provide the modified or derived work back to the community for usage by others, while some licenses allow the user to modify or have derived works and the users do not need to provide their work back, in fact they can even copyright their modified work under their name and distribute it. The most common licenses are the GPL, BSD and MIT licenses. GPL is the most widely used free type of license and has a strong copyleft requirement. In any scenario of distributing the derived works, the source code of the work has to be made available under the same license. Linux is a major example of the GPL license. The MIT license is again a free permissive license which allows the users to do anything with the code with proper attribution. OPC UA is an example of a MIT license. BSD alike the MIT license also is a free permissive license which allows users to do anything with the code with proper attribution. Ethernet POWERLINK and openSAFETY are examples of a BSD license. Thus users can make use of these established global open source automation technologies in their systems in-order to meet their customer demands.
