It´s ironic that the world got wired together with personal computers and the Internet before we could get shop-floor molding machines wired to the front office — but that´s changing with the advent of PC-based controls on standard molding machines.
As PC controls continue their advance to the shop floor, communications with the front office, Internet access and e-mail will be as easy on a molding machine as they are on your office PC, along with all the other capabilities we take for granted on PCs: imaging, databases, spreadsheets, computer-aided design, audio and others.
While it´s exciting, it will also create some anxiety. What´s happening is the fall of the "Microchip Curtain."
On one hand, it´s great to see democracy come to the controls side of molding machinery to facilitate increased productivity. But new democracies can run haphazardly. Buyers find themselves overwhelmed with choices — they now need to make decisions and commitments that were made for them under the old regime.
The incredible evolution of the PC is driving the change. Traditionally, machine controllers with enough capacity to manage a molding process were built around specialized hardware and software. This was because injection molding process control requires a great deal of computing power that was unavailable through general-purpose electronics. Only the largest electronics firms could make the investment in time, equipment, and expertise to produce molding machine process controllers.
The advent of PC technology in the 1980s created an opportunity to have extremely high processing power available for a lower cost. The first and most obvious application was as a user interface — the screen information and displays — to the control system.
By 1994, it was common to see an industrial PC used as the operator interface of a control system, while a dedicated sequencer ran the molding machine in the background in real time. Real time means the sequencer could respond to events on the molding machine in less than 1 millisecond.
Encouraged by the successful combination of the PC and sequencer, development work continued to find a way to replace the sequencer with an industrial PC. The quiet evolution of PCs answered this need, with improvements in hardware and operating-system software leading to today´s revolution — a new generation of "totally PC" molding machine process controllers that deliver unprecedented power, flexibility, and openness, while decreasing manufacturing cost. An example is the patented Milacron Xtreem control introduced at NPE ´97.
How does a PC-equipped molding machine affect the business? Largely by facilitating the flow of information in a way that´s never before been possible. PC-based controls will enable a link in information systems, from the machine level to the enterprise level.
In the past, separate front-office and shop-floor information systems — which should be fully coordinated — could be bridged only with a paper system or an expensive MIS solution, such as a mainframe computer. With PC machine controls, shop and office information systems are one and the same. Now the front office can have real-time information down to the machine level, because molding machines will appear as PCs on the network.
All basic hardware and software are the same from office to shop, leveraging the cost for software purchases, start-up, training and support. Also, the same people who support the Windows office PCs can support the shop controls, streamlining costs.
When factory service is needed, over-the-counter, remote PC access software can allow a factory technician to check the control thoroughly via modem. At least one machine tool company already has the means for its factory technicians to videoconference with a machine user while trouble-shooting the PC-based control. If the problem requires a field service call, the factory technician is more likely now to have completely diagnosed the problem and have the correct parts on the first visit.
Among the potential drawbacks with PC controls are the issues of security and viruses. Both have been addressed in the office environment for years. Fortunately, Windows NT has many security provisions built-in to keep one operator from sabotaging the machine for others. Nevertheless, this needs to be looked at very carefully at the outset, with all necessary safeguards put in place before problems develop.
Configurability is also an issue, as it already is for the office PCs. You have to set up all the controls the same to allow operators or service technicians to move from machine to machine and find features in the same place, working the same way.
PC controls allow virtually unlimited choices, so management has to exercise discipline over the process. You don´t want operators or foremen adding their own software or screen savers, only to find out the molding machine won´t work anymore.
Rapid technological evolution and obsolescence may be issues for hardware, support, and spare parts, just as they already are for PCs. Could you still get support for a PC or software sold in 1984?
Fortunately, many traditional industrial controls suppliers have made the transition to PC-based hardware. Yes, their products cost more than the corner computer store´s, but you are paying for real added value: a hardened industrial product (and there is a difference) and a commitment from the manufacturer to provide decades of support.
Sparer is manager for controls and automation development at Milacron Inc. in Batavia, Ohio.