Vance VanDoren, Control Engineering -- 12/15/2001
Back before "control engineer" was ever used as a job title, process controls were
the purview of mechanical engineers, who installed pneumatic feedback devices to
regulate continuous variables such as temperatures, pressures, and flow rates.
There were often hundreds, if not thousands, of such "loops" in a large processing
facility, but each operated independently of the others and generally required more
effort to install than to configure. Electronic process controllers came on the
scene in the 1960s, but these too were more often a matter of pliers and screwdrivers
than software and algorithms.
Discrete controls also originated as a function of the traditional engineering disciplines.
Mechanical cams and gearboxes, followed later by ladder-like networks of electrical
relays, were the first devices used to automate a sequence of manufacturing operations.
Such controllers could only be "programmed" by reshaping or rewiring their mechanical
and electrical components.
The first computer-based controller, introduced in 1969, was much easier to configure,
but it added little to the techniques available for discrete control. It was programmable,
though not in a general-purpose computer language like Fortran or C. Instead, it
operated according to a set of graphical instructions that mimicked the appearance
and operation of old-fashioned relay ladders. Even that computer's name—the programmable
logic controller—was chosen to avoid the stigma of newfangled, unproven technology
that electricians often regarded with suspicion.
Hardware history
The hardware-oriented history of control engineering is even more evident in the
field of computer numerical controls (CNC). CNCs date back to December 1946 with
the invention of a machine that could automatically direct a machine tool to cut
helicopter rotor blades according to contours recorded digitally on a stack of punch
cards. However, even this control technology relied primarily on computing hardware
that simply translated digital contour data into the required path for one machine
tool.
In the next few decades, the major CNC engineering effort went into making machine-control
hardware more reliable and efficient. Today, the focus is on expanding the scope
of control projects from individual machines run by factory-floor personnel to enterprise-wide
applications that involve multiple machines and most departments in the organization,
even vendors and customers from outside of the company. In the early 1960s, about
75% of the workforce in a CNC company were on the manufacturing floor. By the mid
1990s, 75% were in the office.
Similarly, about 80% of research and development engineers in the CNC field of the
1960s were hardware oriented. They designed flip-flops, counters, I/O interfaces,
timers, and math units with transistors, rather than the vacuum tubes used in 1946.
For the large machine tools, the first beneficiaries of numerical control, a rule
of thumb stated that the control would cost about 15% of the total machine. Each
new design over the years showed much greater capability with lower-cost hardware,
but the 15% share for the controls remained constant because new features were always
being added. Many involved new I/O devices or peripherals, but most were improvements
in the sophistication of the controls and the software implementing them.
Paradigm shift
Similar trends have unfolded in the process and discrete control markets, especially
with the advent of PC-based or "embedded" controls. An off-the-shelf PC from a local
electronics store can run an entire factory, if equipped with the necessary I/O
equipment, software, and programming.
This shift in control engineering, from an exercise in assembling the controller
to designing and configuring the complete automation system, has resulted in the
hardware being viewed as more of a commodity and the software as the high-technology
element in the mix. It has also led to the proliferation of control system integrators
(CSIs), whose job it is to make all the components of a client's automated factory
work together.
Many end-users and OEMs now rely on CSIs for contract engineering services because
it can be more cost effective than maintaining a full-time control engineering staff
in house.
A survey of the integrators listed in this and previous edition of the Automation
Integrator Guide bears witness to this trend. Although hardware oriented skills,
such as implementing and maintaining process controllers, instrumentation, and programmable
controllers remain among the most widely reported engineering specialties, software
and design-oriented skills, such as factory-wide automation, human-machine interfaces,
and project management, are on the rise. "Computer software engineering" is now
reported as an engineering specialty more than twice as often as "computer hardware
engineering."
CSIs' views
A related study, "Industrial Automation and Control System Integrators" from Bull's
Eye Marketing (Fond du Lac, Wis.), also shows how control system integrators are
becoming involved in more facets of industrial automation than just the equipment
on the factory floor. The study was based on a survey of 227 CSI executives in the
factory automation arena, representing both discrete and process control (68.5%
and 31.5%, respectively). More than half the respondents were from integrators doing
more than $2.5 million per year, and 44% employed more than 25 individuals. There
were 14 industries in which at least 30% of the integrators had each done applications.
The top three were food and beverage, material handling, and chemical.
The study divided the work that CSIs do into 19 categories, and the respondents
were asked to rate for profitability with "0" being "low profitability," "1" being
"average profitability," and "2" being "high profitability." The mean ratings ranged
from 0.59 to 1.34, indicating that some tasks were considered more than twice as
profitable as others. The least profitable tasks included installation, start-up,
maintenance, panel assembly, PLC application, and CNC application. These are all
closely related to implementing one machine on the factory floor, and they're fairly
closely related to control hardware.
At the other extreme, the tasks of supervisory control and data acquisition (SCADA),
networking and communications, distributed control systems (DCSs), system design,
system consultation and custom programming were among the tasks reported as most
profitable.
These results show that system integrators profit most from tasks involving engineering
skills that are more sophisticated than turning a screwdriver.
High-tech projects, such as supervisory control, networking the enterprise, distributed
control, and providing an overall system for the facility, also tend to involve
upper layers of the factory's management personnel, and not only the factory-floor
supervisor.
The reasons behind this trend are driven by supply and demand. There is a direct
relationship between the level of skill or knowledge required to complete a task
and its profitability. There are many more engineers and technicians who know how
to build panels, install electronics, and perform start-ups than those who know
how to perform SCADA, networking or DCS work. The more highly skilled person is
generally responsible for new and unique jobs. Once new tools ease the complexity
of these tasks, these highly skilled professionals may then find new areas to conquer.
Looking to the future
Where might these new areas be in the years ahead? There is still much to be done
at the highest enterprise level (enterprise resource planning and manufacturing
execution systems, for example), but another fertile area is improving the way an
organization interacts with its customers and vendors to maximize information exchange
and minimize human error.
The study's respondents give a hint about future work they anticipate in their views
on specification authority. Respondents were asked to state the degree to which
their decision-making influence or specification authority will change relative
to the customer's influence over the next five to seven years in each of the nine
product categories shown in the accompanying chart.
In five product categories, CSIs expect to be much more influential in selecting
vendors and products in the future, and these all tend to be growth products. With
more traditional products, the study's respondents expect the power of the purchase
decision to remain similar, although those expecting an increase in influence far
outstrip those expecting a decrease, even with less sophisticated products.
It seems that the CSIs have been working their way into more sophisticated applications
over the last decade or so, and they see their influence increasing substantially
now that they have considerable experience with these products. As their influence
grows, CSIs are also expecting some very dramatic increases in the purchase volume
of the nine categories over the next five years.
Not surprisingly, their forecasts show much higher purchasing increases among more
profitable products, but they also project growth in all nine categories. It is
also interesting to note that the midsize CSIs (with annual revenues of $1 to $4.9
million) expect substantially greater increases than do the larger ones ($5 million
and up). Where exactly these trends will take the CSI industry in the future is
anybody's guess. Look for future editions of the Integrator Guide or search on-line
at www.controleng.com/integrators for clues.
For more information about "Industrial Automation and Control System Integrators,"
contact Bull's Eye Marketing at info@bullseyenet.com.
The catch in finding qualified integrators
The increasing emphasis on software over hardware among CSIs' clients has also had
a downside for end-users. Some integrators now do just the design, configuration,
and programming work, preferring to farm out panel construction and installation
chores to subcontractors.
However, that isn't the problem. In fact, subcontracting arrangements can be profitable
to CSIs, who need to focus their attention on the high-tech tasks that they do best.
End-users can benefit as well when specialists are brought into a project when they're
needed. The problem is that, without the need for equipment stocks or panel assembly
facilities, there is now a very low cost of entry into the CSI business. Virtually
anyone with a PC and a business card can theoretically start bidding on projects,
with or without the benefit of any previous experience, financial backing or business
sense.
The Control System Integrator Association (CSIA, Exton, Pa.) has recognized this
problem, and has taken measures to address it with its "Registered Member" program.
The idea is to provide an auditing service to provide differentiation in qualifications.
Integrators that pass the third-party examiner's rigorous review are entitled to
style themselves as "Registered Members" of the CSIA and display the CSIA's seal
of approval. The CSIA also offers educational materials that integrators can share
with their clients to explain the benefits of considering criteria, such as CSIA
registered membership, rather than only considering the low bid. For more details
see the following story, "The Control System Integrator Quest."
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