Interface standard will simplify digitalisation considerably

Global networking as envisaged by Industry 4.0 will only succeed if the data ex-change takes place via standardised interfaces over the entire process chain. In its new umati brand, the VDW (Verein Deutscher Werkzeugmaschinenfabriken - German Machine Tool Builders' Association) is developing such an open interface standard for connecting machine tools to higher-level IT systems.

This significantly simplifies digitalisation and allows medium-sized companies to tap into the poten-tial of modern production environments. This will be demonstrated in the form of a complex showcase at EMO Hannover 2019.

Visitors will be treated to a large-scale demonstration of how umati works on the umati stand in Hall 9 at EMO Hannover. It is planned to link up at least 100 ma-chines from national and international manufacturers, and to present the latest de-velopments and the internationally agreed draft of the Companion Specification.

The VDW's umati interface (universal machine tool interface) based on OPC UA aims to ensure that data from machines equipped with different control systems is routed through an open, standardised connection. It is comparable to a USB stick. "It's about creating something that the computer industry has long benefitted from," points out VDW Chairman Dr. Heinz-Jürgen Prokop.

umati meets a wide range of customer requirements

Digitalisation has long been part of the daily business of machine builders. The companies have had plenty of time to formulate their expectations and ideas for the practical application of umati. "At Profiroll, we're currently concentrating on ana-lysing machine data in order to achieve ever finer tolerances while ensuring pro-cess reliability. In recent years, for example, we've developed a hardness compen-sation system that irons out fluctuations in the infeed material on the process side – an intelligent machine, so to speak. We don't yet have large-scale processing of machine status data. We initially worked elsewhere within the VDW on developing the umati standard, since the in-house resources for software development are lim-ited," says Dr. Stephan Kohlsmann, Managing Director of Profiroll Technologies GmbH from Bad Düben.

"Our customers are increasingly demanding part-specific data and also information on the status of the machines and the quantities pro-duced. We machine tool manufacturers know which information operators are in-terested in and are therefore ideally positioned to define a standard and agree it with the control manufacturers. In the future, operators of a wide variety of machine tools can expect to receive the data they need in a uniform context, in a uniform cycle and in a uniform data format. This is a huge step forward because then they only have to take care of the specific, standardised storage and processing of da-ta," he continues.

Regarding the potential savings and improvements that can be achieved through a uniform interface standard, Kohlsmann points out: "Today, machine manufacturers receive a set of requirements from each individual customer regarding the provi-sion of key data in their own unique format. This is enough to justify time- and cost-intensive engineering processing and adaptation of software on a project-specific basis. The umati standard makes it possible to fulfil many different customer re-quirements. This is a revolutionary project in mechanical engineering and compa-rable to the new mobile transmission standard 5G which will enable developments such as autonomous driving, augmented and virtual reality or real-time applications to become part of everyday life."

Basis for dynamic, future business models

Digitalisation is also crucial at Samag Saalfelder Werkzeugmaschinen GmbH, both in automotive series production in its role as a plant operator, but also in the ma-chine tools segment. "IoT or Industry 4.0 are based on having knowledge of the da-ta produced and its significance during the lifetime of a system, and also on the use of a common language which enables all system elements to understand each other. Samag Machine Tools creates the conditions for this through close coopera-tion with the development departments of the premium suppliers," says Samag Managing Director Roland Emig.

"Optimised, secure and standardised data access to the planning and/or control systems allows efficient utilisation of machines and plants, avoidance of unplanned downtimes and optimised planning of availability and capacities," Emig continues. In addition, this common approach provides the basis for dynamic, future business models such as pay-per-use, predictive maintenance, smart monitoring, smart data services and capacity on demand.

"There is also considerable potential for easier exports through the immediate im-plementation of machinery and equipment in existing organisational structures  without national adjustments. In addition, there is the potential to reduce the num-ber of variants, the possibility to safeguard concentrated expert knowledge within the company, and improved release security and data security," emphasises Emig.

Technical basis for global networking standard

The specification being created is based on OPC UA (Open Platform Communica-tions Unified Architecture) – a data exchange standard for manufacturer- and plat-form-independent industrial communication. "The standard provides both a data model and a communication structure for implementing parameters and semantics in an open, standardised form. That's why it's spreading so rapidly, especially in mechanical and plant engineering," says Dr. Alexander Broos, Director of Re-search and Technology at VDW, explaining the technical basis. The implementa-tion is comparatively simple, since development packages can be used to config-ure and customise a so-called OPC UA server. (see also interview.)

Uniformly defined parameters, which are described and published in the form of an OPC UA Companion Specification, play an important role. The standards are fund-ed by the OPC Foundation, which supports the publication and dissemination of OPC UA standards. The OPC Foundation is an industry consortium that creates and maintains open connectivity standards for industrial automation devices and systems, and therefore represents a key partner. The VDW has been a member since June 2018.

The growing importance of digitalisation is a key topic at EMO Hannover 2019. The "IoT in Production" exhibition area offers a complete overview of key aspects of digitalisation, such as Industrial Security, Data Analytics, Industrial Cloud Services, Process Monitoring, Predictive Maintenance, Artificial Intelligence AI, Machine Learning and Big Data Management.

Interview

Flexibility is crucial for a marketable standard

Dr. Alexander Broos is Director of Research and Technology at VDW. He explains the global challenges that need to be overcome in implementing a uniform OPC standard.

Dr. Broos, what is the current status of umati?

We're basically working on umati 1.0 right now. This will then evolve, as software usually does in practical use cases. At some point there will be umati 1.1 or umati 2.0. Getting to that point is a complex process in terms of standardisation. Basically this means reacting to changes, if necessary by releasing an update. And we have to decide what backward compatibility to incorporate.

To what extent is umati a rival to the US standard MTConnect?

Both umati and MTConnect are open interfaces. Umati is based entirely on the freely configurable OPC UA communication platform. OPC UA provides a frame-work which regulates how the machines correspond with each other. The precise content of the communication can be regulated individually by describing parame-ters in an OPC UA Companion Specification, which is a kind of dictionary. Umati and MTConnect are also coordinating on developing this uniform dictionary. There are, however, some differences with regard to the implementation. Here, umati is striving to convert the special domain knowledge of the machine tool industry into semantics and an information model.

What role is the VDMA playing here?

The OPC Foundation has a cooperation agreement with the VDMA (German Engi-neering Federation). Under this, the VDMA acts as a German and European plat-form for all branches of mechanical and plant engineering and as a strategic part-ner of the OPC Foundation. Companies that want to implement OPC then use the sector-specific VDMA 'standard sheets'. The VDMA Robotics + Automation and Plastics + Rubber Machinery associations in particular have already developed their own standards. Others, such as packaging machine manufacturers, are also working on this. We in the VDW are therefore operating in an expert environment, are integrated into the processes of the VDMA and can benefit in the long term from the resulting synergies.

What does this diversification mean for the manufacturers in the individual industries?

Of course, industry-specific standards are important, even unavoidable, for OPC UA. The different industries are too different for it to be otherwise. And there will always be manufacturer- or customer-specific data requirements that are impossi-ble to standardise. Nevertheless, there is always a certain degree of overlap across all sectors. This should then be covered in a general section which is appli-cable to all industries. The VDMA takes care of the corresponding coordination. Of course, this process demands a degree of flexibility from the individual participants in reaching the common goal: a standard that can be applied as universally as possible. However, I'm optimistic that we'll move relatively quickly together towards achieving this.