Measure Surface Deviation

Description

This Step is used to calculate deviations between surface data and 3D model.

Before using the Step, ensure that a 3D model file (in STL or PLY format) and its corresponding pose file (in JSON format) are prepared. Otherwise, the Step cannot be executed.

Workflow

The process of configuring this Step is shown below:

measure surface deviation workflow
  1. Configure the input. Connect the ports manually in the graphical programming workspace or select the input under Input in the parameter configuration panel.

  2. Specify the model file format and model file path.

  3. Select the model surface type and model pose JSON file path.

  4. Select the deviation calculation result.

  5. Select the Output item under the Output tab.

  6. Run the Step and view output.

Parameters

Parameter Description

Model File Format

Select the format of the 3D model file to be loaded. Only supports STL and PLY formats.

Model File Path

The path to the 3D model file.

Model Surface Type

Select the reference surface (the model’s top or bottom surface) for deviation calculation.

Model Units

Units used by the model.

Value list: millimeters, meters

Model Pose JSON File Path

The JSON file stores the pose information of the model’s surface data.

Deviation Calculation Result

Select the deviation calculation and statistics result saved via Deviation Viewer to calculate the output items Feature Points and Deviation.

See Deviation Viewer to learn more about the tool.

Output Description

Select the output item(s) to add the output port(s) to the Step, and the corresponding data will be output after the Step is run. You can select the output according to the actual measurement requirements.

If you select an expandable output item (with a ▶ on the left), you should expand it by clicking ▶, and then set the Min and Max values to determine the acceptable range. If the output value falls within the acceptable range, the measurement item is judged as passing (OK), or else it is judged as failing (NG).

Output item Description

Surface data

The surface data obtained after comparing the surface data with the model, and the Z value represents the deviation.

Feature Points

The center of each circle ROI drawn in the “Deviation Viewer.”

Deviation

The mean deviation within each circle ROI drawn in the “Deviation Viewer.”

Troubleshooting

  • For common errors, see Error Code List.

  • If the error code is inconsistent with the error message, please contact Technical Support for help.

CV-W4101

Error: The number of points in the PLY file must be greater than or equal to 3.

Solution: Check the file and make sure the number of points in the PLY file is greater than or equal to 3.

CV-W4102

Error: The number of points must equal the number of normals in the PLY file.

Solution: Check the file and make sure the number of points is equal to the number of normals in the PLY file.

CV-W4103

Error: The magnitude of normals must be equal to 1 in the PLY file.

Solution: Check the file and make sure the magnitude of normals in the PLY file is equal to 1.

CV-W4104

Error: The PLY file contains invalid point(s) (NaN values).

Solution: Check the file and make sure the PLY file contains no invalid points.

CV-W4108

Error: Cannot find the STL file in the specified file path.

Solution: Select the correct file path.

CV-W4109

Error: Invalid STL file.

Solution: Check the file and make sure the file is valid.

Is this page helpful?

You can give a feedback in any of the following ways:

We Value Your Privacy

We use cookies to provide you with the best possible experience on our website. By continuing to use the site, you acknowledge that you agree to the use of cookies. If you decline, a single cookie will be used to ensure you're not tracked or remembered when you visit this website.