Smart Manufacturing Connectivity for Brown-field Sensors Testbed
The additional path established by the Y-
Gateway uses OPC UA, meaning that the Y-
Gateway accommodates an OPC UA server
to provide the sensor data to an OPC UA
client integrated within an enterprise IT
system. In the Testbed, a consistent mapping
of IO-Link data to OPC UA was defined and
implemented which allows for the easy
integration with the IT system. This mapping
is currently being standardized in a joint
effort of the IO-Link Community and the OPC
Foundation. The Testbed provides essential
input here and delivers a reference
implementation at the same time.
(SAP PCo) that is a kind of hub capable of
connecting to either of the two systems.
T ECHNICAL C HALLENGES
Performance
The additional data processing required for
the IO-Link/OPC UA conversion on the Y-
Gateway shall have minimum impact on the
real-time operations, meaning that the
latency of the cyclic exchange of sensor data
with the PLC shall not significantly increase.
Testbed deliverables include a specification
on how to measure the additional delay that
occurs between a sensor and the governing
PLC. The specification considers all latency
contributions within the real-time control
system and determines how to measure the
effect of the additional data processing.
Measurements were carried out according
to this specification. Software and hardware
optimizations were performed to minimize
the impact.
The enterprise IT systems used in the
Testbed are:
1. SAP Manufacturing Integration &
Intelligence (MII) which is an SAP
application
for
synchronizing
manufacturing operations with back-
office business processes. In many use
cases it is configured as a data hub
between SAP ERP and operational
applications, such as a manufacturing
execution system (MES), and provides
analytics and workflow tools for
identifying problems in the production
process
and
improving
its
performance.
2. SAP Cloud Platform which is a platform
as a service developed by SAP for
creating new applications or extending
existing applications in a secure cloud
computing environment managed by
SAP. The SAP Cloud Platform integrates
data and business processes.
Security
The additional communication path is
established underneath the governing PLC
which normally implements security
mechanisms to protect the attached devices
from unauthorized access. So, a door is
opened to attacks through this additional
connection with the enterprise IT system,
which is normally blocked by the PLC. That is
why sufficient levels of endpoint protection
for the Y-Gateway and protection of the
communication via the additional path are
essential; similar to those implemented
within the PLC at the control level. Endpoint
security is achieved, for example, through
the implementation of a Trusted Platform
Both systems use the OPC UA server
integrated within SAP Plant Connectivity
- 81 -
IIC Journal of Innovation