CMM Contact Measurement (Probing)

Our contract measurement services include a variety of short-range (< 20 feet) and long-range (20 to 900 feet) technologies, which use both contact and non-contact processes.

The Difference

Contact Measurement

A method of collecting single points relative to each other in small or large volumes. This information can then be used for evaluation, inspection, layout or basic geometric reverse engineering. For capturing localized or small volume information, digitizing or articulating arms are ideal. For larger volumetric projects, optical solutions like laser trackers and photogrammetry CMMs perform best.

Non-Contact Measurement

Three dimensional (3D) white light scanning or laser scanning, sometimes called "digitizing", is the process of capturing the geometry of existing physical objects through the use of laser-emitting camera-like devices. Exact Metrology's laser scanning technologies capture the 3D definition of both small and large objects.

For short-range, contact measurement, we offer our PCMM solutions. These include two styles of touch probing (digitizing) that provide high-accuracy measurements of objects that fit within an 24 foot envelope.

PCMM Highlights

Portable coordinate measurement machine (PCMM) is the perfect term for metrology equipment that uses the touch probe approach of a stationary CMM but offers the flexibility of portability and large measurement ranges. These metrology tools are ideal for applications that require:

• High accuracy
• Hundreds of measurements on geometric shapes
• Measurement of large objects (too big for a conventional CMM)
• Measurement of objects in-site

PCMM Technologies

ROMER arms

• Measurement ranges of up to 12 feet
• 6 DOF (degrees of freedom)
• Accuracy of 0.001 to 0.002 inch (part dependent)

NDI OPTOTRAK optical tracker

• Untethered, walkabout scanning solution
• Measurement range of 5 to 24 feet
• Accuracy of 0.001 to 0.002 inch (part dependent)

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Short-Range Scanning and Long-Range Metrology

For many projects, we will combine the short-range PCMM tools with our short-range, 3D scanning equipment. This delivers a perfect blend of high precision for feature locations and geometric measurements and high density for complex or organic shapes.

And when the parts are too big or too far away to be measured with the short-range tools, we apply our long-range technologies, which use both 3D scanning and PCMM approaches at distances of up to 900 feet.