Why is this idea so seductive?
A couple of forces are driving the design of automation systems toward the simple. One is the topic I seem to cover every couple of months: the lack of trained and knowledgeable automation professionals now and for the next 10 years or so. Automation professionals who have just finished training simply don’t have the experiential knowledge base to understand why things are done just so.
For example, ask any random automation professional why the damping of every loop controller is the way it is. I’ll wager a significant amount that you’ll have trouble finding somebody who knows off the top of his or her head. There is a reason. The controller algorithms were written originally for pneumatic controllers—what we used to call “huff-and-puff” systems—and you had to allow dead time for the air surges to damp themselves. Even though very few pneumatic systems are left, the algorithms remain. And it’s important for new automation professionals to know why. This isn’t the only example of experiential knowledge value, just a prominent one.
The other force is McNealy’s Law. Scott McNealy, co-founder and chairman of Sun Microsystems, formulated the “other” Silicon Valley law: Never argue with market forces. Sometimes this is translated as, "COTS [commercial off-the-shelf software] always wins.”
The modern DCS architecture was born when the DeltaV development team made the calculated guess that somebody would develop a practical, managed Ethernet switch…and Cisco did. It’s no longer necessary to produce all of the proprietary widgets automation systems used to require. Look at the proliferation of USB devices!
What we have is younger and less experienced automation professionals or older, overworked ones. They no longer have time to “design from scratch.”
This happened as the software development industry matured too. Nobody writes much assembler code any more. People use building block libraries and connect code modules that are already tested, debugged, and known to be stable.
The same thing is happening in automation system design. We’re seeing the introduction of higher level development tools, both hardware and software, all the way down to kids’ toy level. Lego Mindstorms is a carefully hidden, fully operational control system design tool—Labview. If we can do this for toys, imagine what we’re about to see for design tools for professional automation applications.
Whether you pay a system integrator to connect the blocks, buy a ready-to-use system from a major DCS vendor, or assemble one yourself, you’re still going to be working with the same building blocks. We no longer have to know how to design a timepiece or build a watch to be able to use a clock to tell time, or use a clock function to do scheduling.
This puts the premium where it belongs—on applications knowledge and real-world expertise.
