Coordinate Measuring Machines (CMM)

Coordinate Measuring Machines - CMM Inspection Systems

A coordinate measuring machine is a specialized device that measures the physical geometrical characteristics of an object by sensing discrete points on its surface with a probe. These systems provide a high accuracy class and traceable calibration, making them the standard for dimensional verification in precision manufacturing. Compared to other inspection methods, a coordinate measuring machine offers superior repeatability and automated data collection for complex components.

Key Features & Specifications

Volumetric accuracy (MPE): $0.9\mu m$ to $4\mu m$ depending on size class according to ISO 10360-2 standards.

Probing system: Touch-trigger probes with $\pm0.35\mu m$ repeatability or scanning probes for continuous measurement at $100 mm/s$.

Measuring volume: Available ranges from $500\times700\times500 mm$ for compact units to $4,000\times2,000\times2,000 mm$ for large-part CMMs.

Temperature operating range: Standard operation at $18-22^{\circ}C$, with thermally compensated models extending to $16-26^{\circ}C$.

Probe qualification: Automatic stylus change magazines supporting up to 21 styli for inspecting complex geometries.

Software integration: Direct interface to PC-DMIS, Zeiss Calypso, and the I++ DME protocol for brand-independent control.

How to Choose the Right CMM

Selecting a CMM involves matching the machine type—bridge, gantry, or portable arm—to the part size, required accuracy, and the operating environment. A shop-floor model like the Hexagon Global S is ideal for near-production inspection where thermal compensation is required, whereas lab-based bridge units are necessary for sub-micron tolerances. Integrating the machine with advanced metrology software is essential for efficient GD&T analysis and automated reporting.