By Matthias Kohlbrand In
These Powerful Capabilities Are Inside a Manufacturing Execution Systems (MES)
An MES or production data acquisition (PDA) is much more than just a data acquisition dialog with a connected database. Logics are stored in the MES backend that define how recorded data is evaluated and processed. It is only a semantic data model that turns the recorded individual data into an overall picture of the current production process and its history.
This also applies to the management of resources in the MES or PDA: the aforementioned semantics and the entire history of a data record are required so that historical data is always correctly assigned, even if there are changes in the organizational structure.
Whenever key figures have to be calculated, completely different specifications from the back end will have an effect, without which, for example, an Overall Equipment Effectiveness (OEE) cannot be validly reported.
In addition, workflows are used to store the entire production process for each article and each variant, including switches, separations or batch formations. Based on this, the
MES can control processes - e.g. operating processes, logistics processes, entries into and from other systems, printing of tickets and labels...
In traceability, too, it is transparent at any time in which workflow step an individual item is located and which path through production it has taken so far. The level of detail at process step level is much more detailed than operating sequences or workflows can be mapped in the ERP.
The added value of MES and PDA is therefore not only in the data entry dialogs – these can even be omitted, as the following examples show.
In the Following Cases It Makes Sense to Trigger MES Functionality via REST Transactions from Other Systems instead of Manual MES Data Entry Dialogs
Cosmino MES Plus comes with its own REST Server, which basically allows to create or modify data in the MES backend via transactions. For example, a Work Item including ID and other relevant attributes can be created in the MES by triggering the corresponding transaction. This makes sense if this part is created at a Work Center where Cosmino MES Plus does not have its own data entry dialog, e.g. because the transaction is triggered directly by the piece counter of the machine PLC and an entry dialog would therefore be superfluous – at least for quantity entry. Or also because it is a production area in which a special system is active that cannot be dispensed with.
Yet another transaction controls the recording of the machine status and, if necessary, the reason for the failure.
There are also transactions that can be used to send orders to the MES or to query data about orders. That's why this method works so well with interfaces to ERP and similar systems, and the customer can add any additional information per transaction without really having to customize the interface.
Of course, transactions also steer processing units from one workflow to another. In most cases, material flow movements are posted at an entry dialog, either manually triggered or by completing a process or an inspection. However, it is not always possible to integrate such a dialog into the work process. In many places, only a hand-held scanner or a scanner built directly into the glove is used for posting. In these cases, there is no display at all. The scan directly triggers the transaction and thus the booking in the MES backend, without any data entry dialog as an intermediate step. Tools, machines or other software involved in the process can also trigger this booking in the MES via a transaction.
In theory, the complete data acquisition and control of the factory can be imagined without a single acquisition dialog. Although in most cases it makes sense not to do without any data entry dialog.
Maximum Transparency through Infinite Data Visualization Possibilities
Another example of the benefit of transactions are special and often individual visualizations which can pull data from the MES via such transactions and the REST Server. “Get commands" can be used to fetch data from the MES for visualizations that have been created by the user or prepared by the COSMINO team. A "post command" is when data is changed in the MES.
So far, our customers' experience with this REST server has exceeded all expectations, so that in the future the REST server can be used by you license-free as part of our software architecture until further notice. Only for interfaces to machine data and ERP will a small license fee be charged as before, even when using the REST server.
A Peek into the Near Future
At this point, a preview of the next evolutionary step of Cosmino MES fits very well: all functions that work today via said REST Server will in the future – also via
REST interface – be carried out via
Digital Twins. Digital Twins are a digital representation of a machine, a tool or a product. They include all data, logics and workflows that are required or generated for the current process. Thus, they are a decentralized copy of the MES backend content for exactly this machine, tool or product, but detached from the database.
In the future, Cosmino's own and external apps and dialogs will no longer have to communicate with the Server and the database, but will be able to exchange the same content directly via the Digital Twins. Since these are distributed and at the same time closer to the process, this architecture is both significantly more powerful and more fail-safe than the previous constellation.
The Digital Twins continue to unload into the database and maintain a connection to the MES backend, regardless of where it is hosted (in-house, but also via public clouds such as Amazon Web Services).
Currently, the Digital Twins are being further developed in various projects. They are already available for use in initial applications.
Based on the added values of this new MES architecture, a complete revision of the entry and visualization dialogs is also taking place. Here, too, the first results will not be long in coming.
