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Part Identification Pipeline

Part identification is the most difficult pipeline to tune because different parts will need special consideration. Even just for the normal components used in the FTP, you need to be sure that the picked components are distinguishable from the tip of your nozzle. Depending on how well you set your camera exposure and other settings, you may need to go back and adjust them, which would require that you re-tune your nozzle tip pipeline to account for the changes.

If you receive an error after picking a component about No Results Found, you need to tune your vision pipeline.

No Parts Found

Setup nozzle

  1. Install a nozzle tip on your first toolhead. In this example we'll work with the N045 nozzle tip. Install the N045 nozzle

  2. Click on the Machine Setup tab in the top right pane. Machine setup tab

  3. Click on the "Expand" checkbox to open all of the features about your machine. Expanding the Machine Config options

  4. Click on Heads > ReferenceHead H1 > Nozzles > ReferenceNozzle N1 Open the Nozzle N1 settings

  5. Click on the Nozzle Tips tab. Nozzle Tip Tab

  6. Click the Loaded? checkbox for the nozzle you're tuning. Loaded Checkbox

  7. Click on Nozzle Tips > ReferenceNozzleTip N045 (or whichever nozzle you're working with). Nozzle Tips Section

  8. Check that the correct toolhead is selected in the Machine Controls Tab. Activate Toolhead

Pick component

To tune a part identification pipeline, you'll need to pick up the component you want to tune. You can setup a feeder and use the "pick" button.

Pick Button For Feeder

Open the pipeline

  1. Go to the Packages tab. Packages Tab

  2. Select the package for the component you'll be tuning. For example, the R_0603_1608Metric package used in the Test Placement. Select Component Package

  3. Check that your nozzle tip is compatible with the package you'll be working with. Check your nozzle tip is compatible

  4. Click on the Bottom Vision Settings Tab. Bottom Vision Settings Tab

  5. Click on the Pipeline: Edit button. Pipeline Edit Button

Edit the pipeline

Reset pipeline to default

If you want to reset your part identification pipeline to the clean default configuration, you can easily update your vision pipeline as follows.

circular symmetry image pipeline

  1. Click the "Copy" button in the code block below to save the vision pipeline to your clipboard.

          <cv-stage class="" name="CaptureImage" enabled="true" default-light="true" settle-option="Settle" count="1"/>
          <cv-stage class="" name="SaveDebugImage" enabled="false" prefix="bv_source_" suffix=".png"/>
          <cv-stage class="" name="MaskCircle" enabled="true" diameter="250" property-name=""/>
          <cv-stage class="" name="ConvertToGray" enabled="true" conversion="Bgr2Gray"/>
          <cv-stage class="" name="InitialBlur" enabled="true" kernel-size="9" property-name="BlurGaussian"/>
          <cv-stage class="" name="Threshold" enabled="true" threshold="230" auto="false" invert="false"/>
          <cv-stage class="" name="SecondBlur" enabled="true" kernel-size="3" property-name="BlurGaussian"/>
          <cv-stage class="" name="results" enabled="true" threshold-min="149" threshold-max="256" expected-angle="0.0" search-angle="45.0" left-edge="true" right-edge="true" top-edge="true" bottom-edge="true" diagnostics="false" property-name="MinAreaRect"/>
          <cv-stage class="" name="RecallOriginal" enabled="true" image-stage-name="CaptureImage"/>
          <cv-stage class="" name="DrawRectangle" enabled="true" rotated-rects-stage-name="results" thickness="2" draw-rect-center="false" rect-center-radius="20" show-orientation="false"/>
          <cv-stage class="" name="SaveDebugWithCV" enabled="false" prefix="bv_result_" suffix=".png"/>
  2. Click the "Clipboard" icon in the vision pipeline window to insert the new pipeline into OpenPnP.

    pipeline clipboard button

  1. Click on the DrawRotatedRects stage. Click on the DrawRotatedRects stage

  2. The main view will show a rectangle around the silhouette of your component.

    1. If the rectangle is not precise around your component, then we need to more clearly distinguish the real component from the toolhead.
    2. If there is no rectangle, we need to loosen the threshold to make the component easier to identify.
    3. If the image looks like the good one above, your pipeline is properly tuned. If you've still been getting failures when homing, you may need to slightly loosen the filtering.

Threshold tuning

The Threshold stage is the most commonly edited stage. It turns the camera image into black and white, which starkly defines the tip of your nozzle. This is especially important for detecting parts, as they should catch all of the light from the upward facing camera LEDs and turn totally white in the image. We need to detect both the position and rotation of the picked component, so a tight, precise rectangle identifying its body is very important. Raise or lower the threshold parameter as necessary until the picked component is outlined precisely.

  • If the image is too dark, lower the threshold setting.
  • If the image is too bright, raise the threshold setting.

Exposure settings

If you're having trouble getting your image to look like the "Good Threshold" image below, it could be that your bottom camera exposure is too high, making it difficult for OpenPnP to distinguish between the part and the nozzle tip. Adjust your bottom camera's exposure, then retry tuning your threshold value.

Threshold Comparison

Test part identification

  1. Go to the Packages tab. Packages Tab

  2. Select the package for the component you'll be tuning. For example, the R_0603_1608Metric package used in the Test Placement. Select Component Package

  3. Click on the Bottom Vision Settings Tab. Bottom Vision Settings Tab

  4. Click on the Test Alignment button. Alt text


If you receive the Part height unknown and camera Bottom does not support part height sensing. error, you need to set your part's height. This lets OpenPnP position it appropriately above the bottom camera.

  1. Go to the Parts Tab
  2. Select your Component
  3. Double-click the Height Column to modify it.

Part Height Error Set Part Height