The term “CMM” or “Coordinate Mesurement Machine” is a term used to describe many types of device used to measure points on physical objects. More generally, we use the term “Industrial Metrology” though of course, this covers a broader range of possible properties that could be measured, not just positions or points. So in this article, we’ll simply stick to the more popular term CMM.
But even here, there are many types of CMMs: Highly stable gantry devices for particularly accurate probing of the positions of points on parts to small articulated arms for the portable, manual measurement of parts. And on any of these mechanical devices, one could attach touch probes for measuring single points or a simple sequence of points, or even laser scanning heads acquiring many thousands of points.
A common feature of almost all CMMs is the fact that they require on-board software in order to visualize the reference model being measured and to perform modeling functions such as comparing the measured points to the nominal design accounting for permitted tolerances. More specifically, such software applications require the following functions:
- Model Import: CAD files can come from any number of sources. Accurate CAD translators speed the work flow by allowing you to import model files from third-parties without concern for file formats. The resulting B-Rep model yields the information necessary for efficiently creating a measurement plan and performing comparisons.
- Comparison:After executing the inspection program on a physical sample, the geometric modeler compares the manufactured specimen to the nominal design model. Other functions such as creating cross sections or performing clash analysis between the CMM and the part may also be used.
- Visualization:To display the part and interactively create inspection programs and data comparisons, a visualization tool is required.
Spatial’s portfolio delivers on these requirements with robust and proven components backed by a full-service organization.
Authored by Steve Hull
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