A coordinate measuring machine without a computer would just be a simple measuring point collector, since meaningful measuring results cannot be obtained without extensive calculations. The main job of coordinate metrology is to analyze the measuring results obtained, in order to arrive at a comprehensive conclusion regarding the dimensional, form and position tolerances of the probed form elements. Other jobs of the computer include:
- Control of the coordinate measuring machine: Control of the measuring axis movement including point-to-point positioning control, linear path control and continuous path control, in the scanning mode or when probing surface grids.
- Correction: Elimination or reduction of all systematic effects on the measuring result, such as guideway deviations, rectangularity deviations, temperature effects or stylus bending.
- Transformation: Conversion of the measured values from the machine coordinate system to any desired part coordinate system, including a fourth machine axis (rotary table) or an articulating stylus system for the stylus.
| - Calculation of:
- Substitute elements: The recorded measuring values are used to determine substitute elements of geometrically ideal shape.
- Combinations and calculations: Further measuring results are obtained from the determined substitute elements by geometric combinations; the measuring results are converted to measuring results suitable for the drawing (e.g. polar coordinates).
- Functions and freeform surfaces: Form elements of irregular geometry on the parts are broken down into partial areas and represented by approximated polynoms.
- Evaluation of the measuring results: The measuring results obtained are compressed, filtered, compared with the default values for the part and documented in measurement logs containing graphics for representing the form and position deviations.
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