A Practical Guide to Using the Industrial Internet Connectivity Framework
usually target users who are plant or
process
engineers,
rather
than
programmers. System integration in
manufacturing is usually done between
devices, not software modules. OPC UA
has very helpful device models that aid
interoperability
between
device
manufacturers.
4. OPC UA has a system discovery
mechanism called an “address space.”
This can be rolled up to a site-wide
server, for instance and the system
connected to a site HMI. This dynamic
system building is very useful for
providing similar functionality, such as
historian storage or HMI viewing, to very
different applications. It is appropriate
where your users control the system
design, not you.
5. Most OPC UA systems end up in
workcells or on process skids. These are
a stand-alone subsystems, usually
incorporating 20 devices or so. OPC UA,
and especially the industrial-integration
software that supports it, targets
workcell integration. The address model
and object-oriented nature directly
support a hierarchy of these workcells.
Users of the other standards rarely
characterize their use cases as
“workcells.”
Determine if you should use OPC UA by
answering the following questions:
1. Are you in discrete manufacturing?
2. Are you associated with the German
Plattform Industrie 4.0 program?
3. Are you building a device that will be
integrated by control or process
engineers or technicians, rather than
software engineers?
4. Will your product be used in different
applications in different systems, as
opposed to one (type of) system where
you control the architecture?
5. Are you building equipment for a
“workcell” or “skid?”
Three “yes” answers to these five questions
point strongly to OPC UA. Let’s look at how
the technology fits these use case indicators:
1. OPC UA is well-positioned for discrete
manufacturing. These applications are
characterized by integrations of devices
into sets of tightly coordinated
subsystems. Since users want to avoid
vendor lock-in, a ready supply of devices
with interchangeable device models is
important.
2. The German initiative Industrie 4.0
recommends OPC UA. Industrie 4.0 is
focused on manufacturing, in contrast to
the IIC that works on IIoT technical
system architectures across verticals. In
a sound bite, Industrie 4.0 is about
making things, while the IIC is about
making things work. They intersect only
in manufacturing systems.
3. OPC
UA
provides more
than
connectivity; it also has pre-defined
device models and a device integration
architecture. Those using and choosing it
OneM2M
OneM2M provides a common service layer
that sits between applications and
connectivity transport. Its emphasis is on
providing common services, on top of
different connectivity standards.
To determine if you should use oneM2M,
consider these questions:
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September 2017