Figure 1: Hierarchy of Information Models in OPC UA
(OPC Foundation, 2019).
cation paradigms such as server-client and publish-
subscribe and means of secure communication like
encryption algorithms. On top of this technological
foundation of data transport, OPC UA defines rules
for data representation and collaborating parties use
these rules to define data representations for differ-
ent domains (OPC Foundation, 2022c). These data
representations are called information models and are
hierarchically structured as shown in figure 1. The
main goal of information models is to describe the
structure of data and its intended usage on an OPC
UA interface. The “Core Information Models” con-
tain the most general aspects, intended to be reused
in all subsequent information models. “Companion
Information Models” are often defined by collaborat-
ing parties and contain data models for a specific use-
case or domain. The models regarded in this work are
all companion information models, described in so-
called companion specifications (CS) (40501-1, 2020;
40083, 2021; 40077, 2020; 40301, 2022; 10030,
2013; 10031-4, 2021; 30260, 2020; 40100-1, 2019).
For individual information models, often defined by a
single company, there is the information model group
of “Vendor Specific Extensions”.
The CS are defined by a so-called joint working
group consisting of OPC Foundation members of the
respective domain. This working group defines the
applications and use cases for the CS, develops the
information model and edits the CS documentation.
Resulting CS do include concepts, that are similar in
principle, but handled differently in various CS. Such
a concept is the representation of production jobs.
Based on the description of all CS published by the
OPC Foundation (OPC Foundation, 2022a), the CS
for Machine Tools, Plastics and Rubber Machinery,
Flat Glass, OPEN-SCS, ISA-95 and Machine Vision
contain an information model describing jobs (40501-
1, 2020; 40083, 2021; 40077, 2020; 40301, 2022;
10030, 2013; 10031-4, 2021; 30260, 2020; 40100-1,
2019).
In OPC 40501, the CS for machine tools, the job
model focuses on times spent per program, part and
job for a communication for systems like MES (Man-
ufacturing Execution Systems). The individual enti-
ties, programs, parts and jobs, have key indicators like
a unique identifier. However, more complex proper-
ties like identification of material lots used in parts or
a detailed representation of subprogram structures is
not included. The machine tools model is represent-
ing the job without providing an interface to control
it. (40501-1, 2020)
Two of the specifications for plastics and rubber
machinery contain information about jobs, namely
OPC 40083 and OPC 40077. In combination, they
provide a communication interface between machines
and MES systems. The job description contains the
planned jobs and related information as well as a man-
agement interface for production data like programs.
Using this interface, some aspects of production like
enabling and disabling automatic runs, can be con-
trolled by an OPC UA client. (40083, 2021; 40077,
2020)
The model of OPC 40301 aims to provide a com-
munication interface between MES or ERP (Enter-
prise Resource Planning) and glass processing ma-
chines. It represents jobs, instructions used for pro-
duction and the material used in production. In addi-
tion to representing the state of jobs, the model also
allows to manage jobs by e.g. adding, deleting, sus-
pending and releasing jobs. (40301, 2022)
The specifications OPC 10030 and 10031-4 are
mappings of the ISA-95 standard defined by the ISA
(International Society of Automation) to communi-
cate between MES and diverse manufacturing soft-
ware systems. OPC 10030 contains models for man-
agement of material, personnel and components. In
OPC 10031-4, these models are extended by means
to control machine jobs. The jobs are connected to
the related material, equipment, physical assets and
personnel. In addition, the interface allows to control
jobs. (10030, 2013; 10031-4, 2021)
The specification of OPC 30260, representing the
Open Serialization Communication Standard (OPEN-
SCS) in OPC UA, utilizes the ISA-95 standard and is
thus implicitly represented in this work, but not ex-
plicitly analyzed (30260, 2020).
In OPC 40100-1, communication among machine
vision systems and between vision systems and con-
trollers or MES is specified. Machine vision systems
are used e.g. to gain information about production
quality and to identify products. In the OPC UA
model, jobs are displayed as “recipes”, and can be
modified over the interface.
Even though the different models exist and are
known to the specification groups, no comparison or
comprehensive overview has been developed so far.
With such a comparison, the individual concepts and
aspects of each model can be compared and be used
as groundwork for a harmonized model containing all
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