PCs come to numerical
CNC manufacturers around the world are turning to PCs to
offer customers flexibility and ease of use
Tokyo, Japan -- Several large Japanese, American,
and European manufacturers of CNC equipment have announced new products based on
the IBM PC. In an industry dominated by proprietary, incompatible control
systems, these introductions provide official (though perhaps belated)
recognition of a new age in numerical control: one in which the PC and the CNC
Once the domain of tiny start-ups such as Delta Tau Data Systems (Northridge, CA), PC-based NC has spread to such powerhouses as Fanuc (and US-based GE Fanuc), Mitsubishi Electric Industrial Controls, Cincinnati Milacron, Siemens, Fadal, NUM, Karatsu Iron Works, IBM Japan, and others. According to Mitsubishi, roughly 60 PC-based systems appeared at the IMTS show last fall in Chicago.
What's driving the trend? Flexibility, capability, cost, and customers. PCs allow users to develop custom front ends, run familiar CAM programs, and get away from cumbersome codes. "We recognize that PCs are the wave of the future," says Henry Glick, national sales manager at Mitsubishi.
Choosing a solution. Two distinct approaches have appeared: Plug a motion-control card into a PC slot to transform the computer into a CNC; or, use a PC as a front end to a conventional CNC. In the latter case, engineers either build the two into the same housing or join them with a network.
Each approach has its advantages. The first rides the wave of ever cheaper and more powerful PCs, making cost almost irrelevant.
The second solution separates the PC from the CNC. Proponents claim this insulates expensive CNC hardware from unnecessary changes provoked by the endless evolution of PC hardware and operating systems.
An example of the former is Mitsubishi's (Mt. Prospect, IL) MELDASMAGIC. Available in the first quarter, MELDASMAGIC is a full-function, four-axis CNC motion-control card that plugs into a standard PC ISA slot. The PC allows users to run familiar CAD/CAM software packages such as Virtual Gibbs from Gibbs & Associates (Moorpark, CA), SmartCAM from Point Control, (Eugene, OR), or SURFCAM from Surfware (San Fernando, CA). Background programming can occur while the card is running.
Most importantly, the card's performance isn't tied to the speed of the PC processor. But for proper screen updates, the company recommends at least a 486-class computer. "This PC/card combination has the same capabilities as our other CNC controls, and you can run any front-end program you want," says Glick.
Karatsu Iron Works (Tokyo, Japan) is also offering an add-in board and software for four-axis control. The board sells in Japan for the equivalent of $1,200 and the software for $330, and is being used by industrial and agricultural equipment makers. Currently, Karatsu's board and software run only on Japanese NEC PC 98 series computers. A DOS version is under development.
Other players include Delta Tau with its new PMAC (programmable multiaxis controller) board for Windows. It's essentially a PC equipped with control card, dual-port RAM board, and proprietary software. And, Cincinnati Milacron quietly unwrapped its Acramatic 2100, a Windows NT-based