In robot vision calibration, what is the purpose of refining extrinsic alignment after initial calibration?

• A. To replace the need for intrinsics calibration
• B. To refine extrinsic alignment to the robot frame and validate accuracy
• C. To measure lighting intensity
• D. To adjust the robot speed

Answer: (B)

Refining extrinsic alignment after initial calibration focuses on the spatial relationship between the vision system and the robot. The camera’s intrinsics describe its internal optics, while extrinsics define the transform from the camera coordinate frame to the robot frame. After the first calibration, fine-tuning this extrinsic transform accounts for mounting shifts, mechanical flex, and setup drift, ensuring the vision measurements map accurately to the robot’s coordinates. It also serves to verify that the system’s pose estimates are truly accurate when used in real tasks. This is why refining extrinsic alignment to the robot frame and validating accuracy is the best choice. The other options don’t fit: extrinsics refinement doesn’t replace intrinsics, it doesn’t measure lighting intensity, and it doesn’t adjust robot speed.