In today's fast-paced environment, manufacturers are implementing advanced technologies
to accomplish the objectives like delivering quality product on time or increasing
production capabilities and quickly introducing new products to the marketplace.
Smart operation is the top priority for manufacturers today. It is the one where
systems across the enterprise are digitally connected and huge volume of data is
shared to gain better visibility and quick decision-making.
For years, the automation industry has been centered on a five-layer hierarchical
architecture - Purdue model of Computer Integrated Manufacturing (CIM) which defines
manufacturing operation management. But today we see there are tremendous technological
innovations and refinements in the processor capability, power consumption, memory
availability and communications channel which bringing change when creating the
CIM reference model of hierarchical data flow in manufacturing operation. It is
a model that defines how information would flow from the shop floor into high-level
enterprise business systems. And, since it is always assumed, each layer would share
the upward flow of information.
With the IIoT (Industrial Internet of things), the model of a hierarchical data
flow is changing instead of point-to point data capturing and sharing it with the
next-level. Due to technological innovations, now the objects of everyday life will
be equipped with microcontrollers, transceivers for digital communication, and suitable
protocol stacks that will make them able to communicate with one another and with
the users, becoming an integral part of the Internet. This will change the whole
perceptive of assets/systems hierarchy in the enterprise. The sensors/actuators
will be embedded in physical objects and linked to wired/wireless network, leveraging
internet protocol for communication with centralized systems.
The industrial automation systems are modeled on 5-layer hierarchical architecture
based on the Purdue Reference Model (PRM). Typically, these layers are:
Level 5 - Business layers : ERP, Plant Performance
Level 4 - Operation Systems : Production planning, MES
Level 3 - Supervisory : Process Control, SCADA
Level 2 - Control Systems : PLC, DCS
Level 1 - Devices : Sensors, Actuators, Instruments
Level 0 - The physical process
However, with the advent of new technology, the difference between layers has started
diminishing. The layers have actually started merging.
Communication
Let us look at the communication between layers from Level 1 to Level 5. Most of
the prevalent deployments require the Level 1 to communicate with Level 2 only.
Controllers in Level 2 process the data and further pass it on towards Level 3.
With the implementation of IIoT and IPV6, Level 1 devices are becoming IP enabled
and hence able to directly communicate with systems residing in other layers.
Similarly, Industrial IP (IIP) allows all layers to communicate with each other
over IP network.
Processing Power
Now, let us look at the processing power at different levels. The earlier Level
1 devices were mostly designed to specific data gathering or actuating activities
and have little processing power. However, with the immense development in computing
& processing power, new CPU chips are available at much cheaper costs. So, in the
same size, power consumption and cost, the Level 1 devices have become more intelligent.
Similarly, Level 2 controllers, which used to process controlling logic & algorithm
and pass on the information to Level 3 for supervisory control, have graduated to
faster, powerful and leaner processors. The processing that is done on Layer 3 computers
is now possible and manufacturers have started embedding them in Level 2 controllers.
Data Gathering
In the traditional model, the Layer 0 devices gather only necessary signals and
each upper layer processes it further, extracting meaningful information from it.
The higher the layer the more meaningful is the information for overall business
context. However, the source data itself was of less quantity and size. Nowadays,
devices have become more intelligent and powerful, hence they not only gathers information
required for control and automation purpose, they also gather and process additional
information that can be directly processed by systems at higher level as well as
can take actions based on instructions received from higher level of systems.
Apps in place of Applications
Intelligence in traditional automation systems are based on large application running
on servers and workstations. Applications can execute multiple functions, are bloated
in terms of computing power required and have slow release cycle for new functionalities.
With the introduction of mobile devices like Smartphone, Tablet or Laptop, 'Apps'
which can do small number of functions for specific activities in really small footprint
in terms of computing power required have become popular. The release cycle of 'Apps'
is also very fast.
This is changing the way automation of systems is handled. User can monitor the
automation systems operation and performance using an App, whereas the O&M team
uses another App for handling the work order and history of equipment maintenance.
The top management uses an analytics App for viewing the overall system's performance
with respect to business context.
As a result of these innovations, the difference between layers has started diminishing
and merging of layers is happening. From 5-layer architecture, it has started becoming
3-layer architecture -
Level 3 - Business layers & Operation Systems
Level 2 - Supervisory : Process Control, SCADA
Level 1 - Devices & Control Systems
Level 0 - The physical process
These have created a new way of solution realizations for both automation system
manufacturers and System Integrators. The solutions do not consist of Product, Software
and Integration, but a significant portion is continual Services - evolving system
configuration, discovery of meaningful information from multitude of data and new
way of decision support systems. New business models have started emerging and we
are going to see new competitive landscape in the market.