Step-Related FAQs

Related Step: Fit Circle to Surface Edge

The caliper length is limited by the feature region’s side length, namely that it cannot exceed 90% of the feature region’s side length. When its value exceeds this limit, the effective value is automatically adjusted to 90% of the feature region’s side length.

The same holds if the feature region is not used. When the caliper length exceeds 90% of the shorter side of the image’s bounding box, the effective value is automatically adjusted to 90% of the shorter side of the image’s bounding box.

Related Step: Transform Surface

If the original surface data are close in position but the transformed results differ significantly, it is important to check whether the directions of the input lines vary greatly. In the Surface Transformation Step, the direction of the input line usually determines the positive direction of the X-axis in the new reference frame. If the input lines differ greatly in direction, the transformed surface data will also vary considerably.

The following example uses fitted lines output by the Fit Line to Surface Edge Step to show the effect of line direction:

As shown in the figure below, in scenarios ① and ② (or ① and ③), the original surface data are very close, and thus the transformed results are expected to remain close as well. If the “Fitted Line Direction” parameter is set to Positive X, the directions of the fitted lines in the two scenarios differ greatly (see the red arrows in ① and ②). As a result, the positions of the transformed surface data show a noticeable difference. To make the transformed surface data closer so that the subsequent processing Steps are not affected, you can change the “Fitted Line Direction” parameter to Positive Y. In this case, the directions of the fitted lines in the two scenarios are close (see the red arrows in ① and ③), leading to closer transformation results.

Related Step: Transform Surface

Yes, it is normal.

Surface transformation is the process of converting the surface data into triangular mesh first, performing transformation according to the settings, and then resampling the data back into surface data. During resampling, a small part of the data may encounter a decrease or increase in data points, which is normal and generally has little influence on the measurement results.

If the decrease or increase in data points is severe and is likely to have a large impact on the measurement results, please contact Technical Support.

Related Step: Alignment

Yes, it is normal.

The model image offset is automatically set to 0 for the generated matching model, serving as the reference position for alignment. If the image input to the Alignment Step has an offset in the X or Y direction, it will be moved to the reference position after alignment to match the model. As a result, you may notice a positional misalignment between the input and output surface data of the Alignment Step when viewing both at the same time in the data visualization area.

Such positional misalignment does not affect the alignment result. The positional changes after image alignment are stored in the Alignment Parameter Group output of the Alignment Step, allowing subsequent Steps to use this information and ensuring consistency throughout the measurement process.