TJ McDermott is senior project engineer at Systems Interface (www.systems-interface.com), a control systems integrator based in Bothell, Wash.
The industrial systems I've encountered are expected to last a long time. If I were an end user, I'd like to see 10 years or more. I know of packaging machinery operating in its fourth decade and still going strong. It takes proper maintenance to make machinery last, but the effort is worth it.
To perform that maintenance, end users need the proper tools. Replacing a worn wrench is easy and not very expensive. What happens, though, when the portable computer that supports the new machinery's PLC, HMI and safety systems gives up the ghost? Computers have a completely different lifecycle than industrial machinery, and the software on them has yet another cycle.
Computer companies would like you to follow a three-year cycle for computers. I think five to six is more reasonable. The Windows XP operating system lasted 10 years, but Microsoft warned us that the update cycle for new operating systems would be more like three years. Software development companies try hard to have an annual release cycle.
Ten years. Five years. Three years. One year. It's getting complicated to maintain that machinery. Let's follow a hypothetical maintenance problem. The shop laptop, when new, is loaded with the then-current OS and programming software, and an RS-232 port to communicate with the machine. Eight years go by, and the computer finally dies. The shop has to have one, and the supervisor has to jump through hoops but gets his crew a new, state-of-the-art replacement.
Then it's time to load the programming software so we can get working on the production machinery. Where's the floppy drive? Our new computer doesn't have one. How do we load the software? Even if the software were very modern for its time and came on a CD, it might not run at all on the new OS. The maintenance supervisor has to jump through more hoops, but gets authorization for a new version of the programming software. Wait. Where's the COMM port? Notebooks don't have RS-232 ports anymore. Have to get a USB adapter for that. Not a retail one either. It has to be a special adapter, at much higher cost. Back through the hoops goes the supervisor.
We are stuck with the update-cycle treadmill onto which the software companies coaxed us. And let's be honest, we like faster software, with new features. There must be a way to improve on this scenario, right? Don't count on longer-lived notebook computers, or software companies slowing down their update cycles. They want to make a profit just as the end user company does with its production machinery.
Fortunately, virtualization software companies might have the solution for us. We'll take a fresh, new and loaded computer with the programming software needed to maintain the production machinery, and we'll make a virtual image of it. That image can be stored on a company server, accessible whenever needed. It can be used on successive generations of notebooks and whatever operating system happens to be current at the time. The image gives us the OS and programming software that were current when our production machinery was new. It eliminates the need to keep the software current. The virtual hardware never gets old, never wears out. This is brilliant!
It also helps to eliminate the frustrations that result from conflicts between rival programming software companies. Create a new virtual computer for a different software package, and they'll never compete for OS resources again. Two virtual maintenance computers. That shop supervisor gets to feel like he's doubled his hardware for the same budget.
It's not all beer and skittles, though. Careful observers will note I've introduced yet another update cycle to our update cycle headache. The virtualization software has one, too. Time will tell if we can rely on virtual machine player software to permit us to run 10- or 20-year-old virtual machine images. I hope so.
