In the last issue, we introduced the necessity of setting up a new reference plane since CAE results are converted to point cloud format.
So how do you set up a reference plane?
Generally, a plane is calculated by the outer product of vectors passing through the three points to obtain the plane equation ax+by+cz+d=0.
However, in actual measurement, it is not often the case that a plane is created from three points.
This is because product drawings often indicate that a reference plane should be created from four or more multiple points.
When creating a plane from more than four points, the coefficients of the plane equation are determined by the least-squares method.
However, the measurement points do not have to be anywhere.
For example, if a plane is created from an uneven surface and the distance to point d is to be calculated
How much difference is there in the measurement results when the measurement point is wide or narrow?
~Calculation results
(1) 48.657mm (2) 48.034mm
It can be seen that there is a difference of 0.5mm or more in the measurement results depending on the way the reference plane is set up.
The above is an extreme example, but if the dimensional tolerances in the drawing are strictly set, OK/NG will be determined depending on how the measurement is made.
It can be said that the creation of a reference plane is an important process in determining whether a product is OK or NG in measurement.
We have many 3D measuring instruments and accumulated measurement know-how.
We also offer engineering services, so why not take a look?
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