To locate a 12 mm ring accurately from a close wrist-camera view, define the snapshot position at the required inspection distance, then calibrate from a separate camera pose where the entire calibration board is visible. The calibration pose does not need to match the saved snapshot pose.
Separate the Snapshot and Calibration Poses
The close snapshot pose establishes the inspection viewpoint. The calibration pose only needs to provide a complete view of the calibration board during the calibration step. Therefore, the board does not need to fit in the camera view at the close snapshot pose.
This separation resolves the apparent conflict between needing a close view of the ring and needing the full board visible for calibration.
Check the Ring Size in the Close View
| Condition | Required image coverage | Action |
|---|---|---|
| Ring too small | Less than 10% of the field of view | Move the wrist camera closer. |
| Usable close view | At least 10% and no more than 60% | Save this pose as the snapshot position. |
| Ring too large | More than 60% of the field of view | Move the wrist camera farther away. |
When the interface provides a Show grid function, one grid rectangle represents the stated 10% minimum. Use the grid to verify the ring scale before saving the close pose.
Define and Calibrate the Close Snapshot Position
- Move the wrist camera to the intended close inspection pose.
- Confirm that the ring occupies between 10% and 60% of the field of view.
- Select Save position during the Define Snapshot Position step.
- Place the calibration board on the same workspace.
- Use free-drive mode to move the wrist camera until the entire board is visible. Do not overwrite the saved close snapshot pose.
- Select Calibrate and complete the calibration wizard.
- Run a location operation from the close snapshot position and verify the measured ring position against the required placement accuracy.
If the far and close snapshot positions reference the same workspace, copy the calibration from the first position instead of repeating the full calibration process. Do not use that shortcut when the positions reference different workspaces.
Why Ignoring the Snapshot Position Is Insufficient
The reported Ignore_Snapposition attempt did not reliably handle the ring's scale change at the much closer distance. That observation does not establish a general limitation of the function, but it supports using a separately defined close snapshot position with valid calibration rather than depending on snapshot-position bypass behavior.
FAQ
Does the wrist-camera calibration pose have to match the snapshot pose?
No. Save the close inspection pose during Define Snapshot Position, then move the camera to a different pose where the entire calibration board is visible before selecting Calibrate.
How large should a 12 mm ring appear in the wrist-camera image?
At the saved close snapshot position, the ring must occupy at least 10% but no more than 60% of the field of view. Use Show grid when available; one grid rectangle represents the 10% minimum.
Can I copy wrist-camera calibration to a second snapshot position?
Yes, but only when the original and new snapshot positions are intended for the same workspace. Otherwise, perform the calibration process for the new position.
