Functions & Layers of Manufacturing Execution Systems (MES)

Basic functions of MES:

The basic functions of an MES system are a collection of software functions that are available independently of a specific product and that allow products based on them to be developed as far as possible using the same modules and with a uniform structure.

Therefore, the basic functions will separate the MES applications from the technical components that form the basis of any IT system. In more detail, the most important functions and objective of the basic function are these:

  • Provision of a uniform interface to the underlying database with the aim of securing database independence

  • Provision of a uniform interface to the underlying operating system with the aim of securing operating system independence. The leading operating systems in which MES systems can be used are Microsoft Windows, Linux and also the Unix derivatives IBM AIX, HP UX and Sun Solaris.

  • Communication facilities delivery
    Examples:
    -Secure network communication on the basis of TCP / IP
    -Production of bus systems

  • Component supply for typical MES tasks
    Examples:
    -Components for displaying business diagrams
    -Components for the temporary storage of data
    -Components for the secure acquisition and checking of data

  • Provision of interfaces and functions to incorporate products with data layer components, application layer and mapping of processes

  • Facilities for technologies interfaces
    Examples:
    -Web services
    -OPC
    -Excel export or XML export
    -Various file formats

  • Product - independent alarm system with the corresponding communications terminal points, email, cell phone, pager and so on (so-called escalation management).

  • Logging, monitoring and tracking functions (for example, to detect and locate fault states quickly).

Different layers of MES:

The data layer is that part of the MES application which is responsible for defining the structures of the database as well as the data stored in them and is therefore responsible for the so-called persistence of the data.

In the overall view, the need to define a data layer shows how products are mapped in the architecture of a modern MES system.

The task of the data layer is to ensure that data for the MES product based on the underlying database system can not only be reliably and permanently written, but also re-read. The layer of data defines the tables and fields required in the database system.

Application layer: business objects and methods:

The application layer depends on the data layer and provides the process mapping with functionality. The application layer deals with the following important requirements.

  • The application layer provides the objects and methods in the process mapping layer to create the business logic.

  • Regardless of the data model, the application layer supplies its objects and methods. This procedure ensures that the application layer will take care of the necessary compatibility and the objects and methods will behave in their normal way if there are changes in the underlying data structures.

Process mapping:

The task of process mapping is to reproduce the actual business logic based on the application layer’s methods and objects. Enterprise logic is a synonym for the term business logic.

Process mapping receives messages including the corresponding data that are processed essentially via “if-then” conditions and the application layer’s objects and methods.

The process mapping thus contains the actual logic of an application or of a product and in addition, makes use of the underlying layers.

Process mapping therefore contains the actual logic of an application or product and also uses the underlying layers.

Interfaces with higher-level systems:

The following sections will provide an overview of the implementation of the “communication and transportation” task to be handled by interfaces to higher - level systems such as ERP / PPS, wage and wage systems.

Possible technical interfaces for this are not only the MES. The reasons why people wonder about this are obvious sincedefinitions of the database structures