Calibration Tools - Sequential N Point

The Sequential N Point Calibration Tool is used to construct a calibration file, using an input feature and its associated real-world coordinates, over sequential image acquisitions.This calibration file can be exported and applied as a Calibration Type in the Set Up Image step and used in other jobs.

Tip: After constructing the calibration, it is recommended that you save the job file. For subsequent calibrations, you can simply load the calibration job, acquire the image and then auto export the updated calibration file to all of the jobs that reference this calibration file.

This tool is useful in situations where you are calibrating an In-Sight vision system and a robot's coordinate system. In this type of application, the robot controller presents an object to the vision system at different locations, one location and image acquisition at a time. With each acquisition, a point is added to the calibration table. Once the robot has visited each location and each point has been saved, the calibration file can be exported and the job file saved.

Note:

This tool requires other Location and/or Inspection Tools to be used as inputs to define the points for the calibration. Assemble the necessary Location and/or Inspection Tools that will be used as inputs before adding this tool.
When using an N Point or Sequential N Point Calibration Tool, the physical and optical set-up (the lens, vision system and the physical relationship between the vision system and the scene being acquired) must be the same for both the calibration and run-time operation. If any of these items is altered, the system must be re-calibrated. Therefore, it is recommended that the same vision system and lens be used to both calibrate and process the run-time images. The vision system and lens must also retain their original set-up and calibration settings. For example, changing the acquisition format (by altering the resolution) or moving the vision system will invalidate the computed 2D transformation that maps pixel to real-world coordinates.