This article was written by Phil Couling, Director, Wonderware Software Product Marketing, Schneider Electric and it was featured in the Pulse Spring Edition 2015 of the Automation.com.
A
lot more than hairstyles have changed since the ‘80s, when I first started
working with SCADA and HMI systems. At that time there were no off-the-shelf SCADA
or HMI software products; every project required a big, complex and expensive
system based on a mini-computer, such as a DEC PDP or VAX; and each project
typically involved modifications and code extensions taken from the last
project. Additionally, requirements definition was an extensive, laborious and
expensive undertaking, and the results dictated the functionality that would be
hard-coded into the system, typically for life.
Most
of the technology we take for granted and consider indispensable today wasn’t
even being imagined by the majority of people 30 years ago. Smartphones, tablets,
the Internet, multi-terabyte hard drives and even full-color flat screen
monitors were barely dreams. Think about it: When Windows-based HMI (known as MMI
at that time) became a reality in 1987 or so, after PC’s had entered the
mainstream and Microsoft Windows had been launched, even a computer mouse was a
pretty cool piece of technology! But now HMI has become so indispensable to so
many industries that, much like it is tough to recall exactly how we got
anything done before the internet, it is tough to recall how manufacturing and
industrial companies operated effectively before PC-based HMI and SCADA
systems.
While
the entire universe of things we call technology is so radically different today
than it was in 1987, we still use the exact same labels—HMI and SCADA—to refer
to the core real-time systems that lie at the heart of so many industrial
businesses, and that is a shame. It’s a shame because those labels tend to
imply there is some kind of equivalence between what is possible with today’s
HMI technology and what was possible with the first generation of HMI
technology. It’s also very unusual. Most products and technology are usually given
or take on shiny new names as they evolve. For example, the telephone became a push-button
phone, then a mobile phone, then a flip-phone, and now a smartphone. And closer
to home, we have CIM, MRP, MRP II and now ERP. Yet the products we continue to label
HMI and SCADA today are as different from their predecessors as the hottest
smartphone is from that old rotary phone. While we can still make local calls
with a smartphone, and still draw graphics on a screen and associate them with
physical I/O using today’s HMI products, if that’s all we are doing with them,
we are really missing out.
While
modern SCADA and HMI systems can still perform the same basic functions they
performed in those early days, business demands, underlying technology and
dramatically changing operator roles continue to influence the rapid evolution
of these systems and deliver solutions for a range of contemporary business
challenges.
Marketers
often talk about “next generation” in the context of software systems, but HMI
and SCADA systems have been undergoing a
series of quiet revolutions for many years now. With all their new, stronger
and innovative capabilities, what is really needed to get the most out of next-gen
HMI is next-gen thinking about how to apply them.
Visualize
the Process and the Business, not just the Equipment
The
first part of next-gen thinking is to recognize that our operational focus has
shifted from being equipment-based to role-based. Operations personnel are now
responsible for ever-larger areas of the plant, if not even multiple plants. To
enable their success, it is necessary to augment or, in some cases, replace the
representation of physical equipment on an HMI screen, regardless of how elegant
and sophisticated that might be, with HMI screens and applications that will help
operators visualize logical portions or logical operations of the process.
Logical portions might now be an entire production line, an entire facility or
even a number of related plant locations across a wide area. A logical
operation might be a screen or screens specifically designed to optimize
process startup and/or shutdown. We refer to the latter as Goal-Oriented
Design, where the HMI/SCADA screens are planned and implemented to support
specific operational goals. This is very different from the majority of P&ID-derived
HMI screens, which are equipment-centric and comprise elaborate depictions of
pumps, vessels, valves and piping. When the principles of goal-oriented design within
the HMI are closely matched to the goals of the business, the benefits can be
very significant.
Present
Actionable Information, not Raw Data
Traditional
approaches to HMI are closely associated with the physical inputs and outputs
of the system under control, with graphical representations on an HMI screen.
In the early days of HMI, instrumentation was very expensive, few I/O data
points needed to be managed and it was quite logical to represent many of them as
values directly on an HMI screen. HMI and SCADA systems represented simple I/O values
in the form of “tags,” and the graphical animations and visualizations possible
with the early HMI systems lent themselves very well to that kind of
representation. The burden of understanding what each of those values meant,
and how to respond appropriately when those values changed, fell upon the
operator, and it frequently required years of experience to interpret that data
properly.
Fast
forward to today. Now there is an overwhelming volume of real-world data and
I/O coming into the system. Continued representation of all of the physical
data using those old-fashioned techniques would not only be an extraordinary
engineering challenge, but would also be completely overwhelming for operations.
The experience and expertise required to make sense of all the data would be extraordinarily
high, and the cognitive burden on the individual would be extreme.
With
next-gen thinking, modern HMI and SCADA systems represent information in the
form of “objects,” which provide a more logical view of all that data. But not
only that, next-gen HMI can add context for all that data, as well as make
standardization and engineering more productive. Using objects to represent equipment
in an automation system is not new, yet many HMI and SCADA implementations do not
fully exploit the benefits offered by the object capabilities the systems have.
Objects allow large collections of related I/O to be grouped together, along
with the limits, alarming information, graphical representation and equipment
connectivity information. When such information is organized and then presented
in an appropriate, understandable fashion, not only can it dramatically reduce
the cognitive burden for the operator, it can enable inexperienced operators to
behave more like experienced operators.
Pursue
Excellence through Situational Awareness
While
the phrase “situational awareness” has been in the industry vocabulary for some
time, most notably in refining and petrochemicals where safety is of utmost
importance, it is now something that benefits most industries.
Situational
awareness is not a feature of
an HMI or SCADA system. It is a valuable benefit
that operators and users derive from using specific best practices when they design
their displays and user interfaces. These best practices were developed in
safety-critical industries, to ensure maximum operator effectiveness and to
mitigate the risk of abnormal situations, which could result in a catastrophe. But
now these proven principles are being applied to help maximize productivity and
availability while minimizing costs, such as raw materials, energy consumption
and waste, and they are generally applicable to a majority of industries. This
is particularly important when we consider the quickly and ever-changing global
economy, competitive landscape, material science, costs and sources of energy,
and so much more.
While
it has been technically possible to apply these principles in an HMI deployment
for a long while, until recently the necessary expertise to do so has been
scarce and expensive, and the architectures of
most
HMI systems did not allow software vendors to offer robust support for these
principles within their products. The burden for developing HMI screens to
these standards was left to the implementation teams. What’s more, a majority
of HMI users, not being familiar with these techniques or recognizing how
beneficial they could be, have not specified the inclusion of situational
awareness in their HMI implementations. The most modern HMI and SCADA systems
now provide deep support for these principles and directly embed best-practice
principles into the product. This can dramatically change the design challenge:
Instead of concerning themselves with the mechanics of building elaborate
graphics, design teams can now focus on: what decisions the operators should be
making to optimize business value. Then they design the user interface from
standard components to facilitate those decisions. With the right HMI software
choice and next-gen thinking, implementing best-practice principles can be
simple, efficient, cost-effective and very valuable.
Evolve
from Perception to Projection to Improve Decision Making
Traditional
approaches of showing simple numerical data or representation of a simple value,
such as a level, pressure, temperature, flow, etc., only communicate simplistic
information to the operator. This is simple perception:
The operator can quickly determine what the value is, but not much else can be
gleaned. How that simple information is actually processed will vary greatly
depending on the experience of the operator. By adding contextual information
regarding the expected value, as well as the current value, the HMI can assist
the operator with comprehension of
the information. At this point, the HMI is actually augmenting the operator’s experience.
The operator is less dependent on his or her ability to remember lots of
process-specific values.
The
next opportunity is to have the system help determine if an action is required
and indicate the consequences of either taking or not taking that action. This
is called projection, where the
system has removed much of that cognitive burden from the operator. The
ultimate level of HMI and SCADA design, allows even inexperienced operators to
quickly grasp the behavior of an unfamiliar system and to anticipate the
consequences of their actions. Modern HMI and SCADA systems fully support this
level of operation through goal-oriented design, effective window structure,
effective color usage, actionable alarm management and effective design
elements.
The
Next Generation
Deep
support for situational awareness and goal-oriented design in HMI/SCADA
software are available today. The latest generation of HMIs don’t merely live
on a single PC screen. They are now part of the infrastructure, providing
critical, actionable information to key decision makers throughout the
organization on a wide and increasing variety of devices: notebooks, tablets, smartphones
and, recently, even smart watches. Contemporary HMI technology allows the
integration of information from a multitude of sources: cameras, maintenance systems,
Web services, inventory systems, planning systems and of course I/O from local
or remote equipment. Today’s HMI/SCADA software already provides incredible
capabilities to make users and operators far more productive, while dramatically
reducing training times for new operators.
Of
course the user isn’t the only stakeholder when it comes to these systems. Next-gen
HMI/SCADA systems make it easy for engineers and system builders to implement,
deliver and maintain these sophisticated features safely, efficiently and within
standards compliance. Next-gen systems also help engineering teams maximize
reuse of existing engineering work, with the ability to scale and support the
implementation remotely.
At
the end of the day, next-gen HMI is really the one you implement next. Compared
to what many companies are actually using now, next-gen HMI and SCADA is
already here, and the pace of evolution continues to accelerate. Ultimately, next-gen
HMI/SCADA is simply next-gen thinking: looking anew at how to use these
products, the problems a new approach might solve and the opportunities for
improvement you might uncover when you think outside the box. Chances are the
software that can help you realize your goals already exists.
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