Iscar Metals
Easier Measuring

"It's all about software," proclaims Keith Mills, president of International Metrology Systems (IMS; Livonia, MI).He's talking about metrology, not general-purpose computing.

"It's all about software," proclaims Keith Mills, president of International Metrology Systems (IMS; Livonia, MI).

He's talking about metrology, not general-purpose computing. So far as he's concerned, "The mechanical structures"—of coordinate measuring machines (CMMs)—"are mature." Not that IMS doesn't have some new gear, of course, which we'll get to in a few moments.

"People measure because they want information. They don't want a stand-alone CMM that doesn't integrate. Software is the tool for integration," Mills argues, sounding a bit like Bill Gates.

In fact, Mills goes on to say that he's borrowing a page from the Titan from Redmond. He notes that it is difficult nowadays to buy a computer that doesn't have Microsoft Office pre-installed. Chances are, a given person is unlikely to use all of the resources provided by that package, but when they need to, say, do a spreadsheet, even if they spend most of their time using Word, Excel is there.

Which brings us to the IMS flagship product, Virtual DMIS. The "DMIS" portion of this name references an ANSI standard, Dimensional Measurement Interface Standard. The purpose is to provide two-way CAD to CMM communications. The point is to provide the means by which users can work in a mode that doesn't require translations. The problem with translators is that things can sometimes be lost, which can be troublesome.

Virtual DMIS is based on DMIS 3.0. Mills admits that other CMM vendors offer DMIS capabilities; this is not unique to IMS. But the differences are, he points out, that they have developed their package with icons and that rather than making this a pricey option, it is the company's standard offering.

Visually, the Virtual DMIS screen appears familiar to anyone who has any familiarity with a Windows package, such as pull-down menus. The software is available for Windows 95 and Windows NT platforms. Second, since the concept is to import information from a CAD system into the CMM for programming, there is also a strong resemblance to a CAD screen, but one that is based on icons that are intuitively familiar to CMM operators rather than to product designers. There are two toolbars located near the top of the page that contain the measuring functionality: the Dynamic toolbar that guides which function to select and the Smart tool bar that has constant updates based on what the operator has done. Should there be any questions, there are animated video clips—160 of them—in the software that can show what the various icons do. This is a whole point-and-click approach. The objective is to provide an environment that is simple enough for a beginner to use, yet one that can also be setup to meet the needs of an experienced professional.

One interesting feature of the software is the 3D solid-model image of the workpiece, fixture and CMM that takes up the main part of the screen. This facilitates programming. So far as the range of IMS CMMs goes, there are full kinematics in the software. Mills says that they are working to get the kinematics for other machines so that a "virtual library" can be established; part of the collection is already established. Because DMIS is measuring machine independent, Mills points out that existing CMMs from other vendors can be retrofitted by IMS to use Virtual DMIS.

On the equipment front, IMS has developed what it is calling a "CMG"—Coordinate Measuring Gage. The machine is called the umpire. The machine, which utilizes a 32-bit PC for control, provides a 14 × 14 × 12 in. measuring volume. There is adjustability of the Z-axis so that the full Z-length can be obtained even with the addition of a probe. The volumetric measuring accuracy with an 8-in. ballbar is 0.00029 in. The resolution in all axes is 0.00004 in.

The umpire is built for use on the shop floor. Some small machines use air bearings. Mills says umpire employs machine tool-like linear guides. Servo-driven ballscrews provide a rapid traverse rate of 590 ipm. To help achieve reliability, the unit is built with fewer than 60 components. The moving elements are protected.

This machine is pretty much plug-and-play: it requires either 110- or 240-volt power, so it can even be used in an office area. In fact, the machine is not only on wheels, but it is less than 30-in. wide and 80-in. high (total footprint is less than 8 ft2), so it can be rolled right through a standard doorway.