From the principle to know VMM&CMM

The video measuring machine is mainly used to measure the plane size of the workpiece. It belongs to the measurement of two-dimensional space.

However, with the addition of a probe or laser module, simple three-dimensional sizes, like the height of the workpiece can be measured.

But for complex three-dimensional measurement, coordinate measurement machine is more suitable.

So what is the difference of measuring principle between the video measuring instrument and the coordinate measurement machine?

① Measuring principle of VMM:

VMM uses its optical magnification system (various lights and zoom lens etc.) to magnify the measured object. After the clear image features are collected by the CCD camera system and sent to the computer, the software algorithm is used to analyze various complex precision parts. The contour and surface shape, size, angle, and position are microscopically inspected.

Since the acquisition source is a non-contact optical system, the acquired image is two-dimensional.

But with the addition of laser modules or probes, simple three-dimensional dimensions such as the height of the hole can be measured.

② The measuring principle of CMM:

Different from the non-contact measurement VMM, the measurement form of the CMM is the contact measurement. The measurement of each measured geometric element is converted into the measurement of the coordinate positions of some point sets on these geometric elements. After the coordinate positions of these points are measured, the spatial coordinate values of these points are calculated through the mathematical operation of the software. Size and shape error.

In my eyes, no machine is perfect. Only the one which is suitable according to the actual measurement requirements.

So how to select the suitable VMM/CMM? Share your ideas below!

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By Polly Peng

TEL:0086-18820249872

UNIMETRO Website