Surface Blob

When Enable Batching is checked, the tool takes an array as input and processes each surface in the array individually. There is no limit to the size of the array, other than processing limitations of the sensor.

This setting is hidden when the tool's Enable Array Output setting is checked.

For more information on arrays, batching, and aggregating, see Arrays, Batching, and Aggregation.

The data the tool applies measurements to or processes.

The X, Y, or Z measurement of another tool that this tool uses as a positional anchor. Positional anchors are optional.

The Z Angle measurement of another tool to use as a rotational anchor for this tool. Rotational anchors are optional.

If enabled, the tool uses intensity data instead of heightmap data. Only available if Acquire intensity is enabled on the Inspect > Scan page during scanning; for more information, see Scan Modes and Intensity.

When expanded, displays the region- and mask-related settings.

Enables regions and displays the region- and mask-related settings (see below).

When you enable regions (see above), the tool displays additional settings related to the region type. For details on the regions supported by this tool and their settings, see Flexible Regions.

For general information on regions and the difference between standard and "flexible" regions, see Regions.

Provides three options: None, Reference Region, and Reference Plane. If the reference type is set to None, the Height Threshold setting is absolute (relative to zero). For the Reference Region and Reference Plane options, see the descriptions of the Reference Region Type and Reference Plane parameters below.

If you set Reference Type (see above) to Reference Region, the tool displays a drop-down that lets you configure the reference region. (For details, see Flexible Regions.) The tool calculates an average height or intensity of the data in the reference region. Height Threshold is relative to this value.

For example, in the following, blobs are detected using a relative height threshold of -0.2 mm, relative to the average in the reference region:

For general information on regions and the difference between standard and "flexible" regions, see Regions.

If you set Reference Type (see above) to Reference Plane, the tool uses the specified plane geometric feature to correct for a tilt of the target. Note however that using a reference plane to correct the tilt distorts the scan data: it sheers the data by the same angle as the tilt. The maximum tilt angle with which you can use the tool therefore depends on how much sheer angle you can tolerate in your application (which can effect the tool's ability to detect blobs). Typically, you add and configure a Surface Plane tool to generate a plane (for more information, see Surface Plane). For information on geometric features, see Geometric Features.

For applications where sheer distortion can't be tolerated, use Surface Transform to correct the tilt (see Surface Transform), and use the latter tool's output as the input for Surface Blob.

For example, in the following, despite the overall tilt of the target, the tool detects the flaws on the surface. (Note the gradient of the heightmap colors, indicating a height difference of roughly 9 millimeters between the lower and higher areas near the dents on the target's surface.)

Indicates whether null points (points where no height or intensity value is available, due to dropouts or regions outside of the measurement range) are filled with the value in Null Fill Value as a general “background level” or to fill gaps to aid in isolating blobs.

If Use Intensity is enabled, the value in Null Fill Value is an intensity.

The threshold above or below which data is considered for being a blob. Use the Threshold Direction setting to determine whether data above or below the threshold is considered.

If Use Intensity is enabled, this setting is Intensity Threshold. Otherwise, it is named Height Threshold.

Determines whether data above or below the threshold is considered as being a blob.

Below: The Height Threshold value is the maximum that will be considered as part of a blob (for example, a dent below the surrounding surface).

Above: The Height Threshold value is the minimum that will be considered as part of a blob (so a raised feature).

The X and Y kernel size, respectively, for morphological opening to remove small areas of data. Use these settings, for example, to remove bridges between areas to properly isolate them or to remove small areas entirely (perhaps caused by noise). Use different values of X and Y to use a non-rectangular filter to adapt the kernel to the kinds of unwanted data you see in the scan data.

The X and Y kernel size, respectively, for morphological closing to fill in holes smaller than the specified kernel size. Use these settings, for example, to fill small areas within potential blobs that may be caused by drop-outs. Use different values of X and Y to use a non-rectangular filter to adapt the kernel to the kinds of holes you see in the scan data.

Provides options to let you find either external blobs only or both external and internal blobs.

External Blobs

Use this option to ignore smaller blobs in larger blobs: only the outermost blob is returned.

External and Internal Blobs

Use this option to include smaller blobs in larger blobs.

If Use Area Filter is enabled, the tool applies an area filter to potential blobs using the values in Max Area and Min Area.

If Use Aspect Filter is enabled, the tool applies an aspect filter (ratio of length and width) to the rotated bounding box that would encapsulate the area, using the values in Max Aspect and Min Aspect.

For example, the lowest dent in a surface is included as a blob if the aspect values are set to 1 and 0.350, respectively (the rotated bounding box encapsulating would be 13.461 mm x 4.782 mm).

In the following, the same dent is excluded if Min Aspect is set to a value greater than 0.354.

If Use Circularity Filter is enabled, the tool applies a circularity filter to potential blobs to measure how close to a circle the blob is, using the values in Max Circularity and Min Circularity . Circularity is determined from area within the contour of the blob and the perimeter of its contour. With increasing perimeter for the same area, circularity is reduced.

If Use Convexity Filter is enabled, the tool applies a convexity filter to potential blobs, using the values in Max Convexity and Min Convexity . Convexity is defined as the (Area of the Blob / Area of its convex hull), and "convex hull" of a shape is the tightest convex shape that completely encloses the shape.

Orders the measurements, features, and surface data of the individual blobs output by the tool. One of the following:

• Position - X increasing
• Position - X decreasing
• Position - Y increasing
• Position - Y decreasing
• Area - Large to small
• Area - Small to large

When Enable Array Output is unchecked, the tool outputs each blob as an individual Surface output.

When Enable Array Output is checked, the tool outputs the blobs in an array called Blob Surface. Be sure to enable Blob Surface in the Outputs section after enabling this parameter. For more information on arrays, batching, and aggregating, see Arrays, Batching, and Aggregation.

Determines the number of blobs the tool outputs as measurements, features (center points of blobs), and surface data. Currently limited to 200 blobs. If Enable Array Output is checked, this parameter is hidden.

Surface data you can use to evaluate the impact of the tool's parameters, after filters are applied, to properly separate the areas corresponding to the defects or targets you need to detect.