Abstract: An independent tube position verification system includes a TV camera (16) mounted on an end effector (EE) of a robotic arm (20) mounted in a steam generator (10) beneath the tube sheet (12) to visually track changes in position as the end effector (EE) is moved across the tube sheet (12) by a robotic arm (20). The tube sheet (12) and the tube ends (14) thereof are illuminated by one or more light sources (18) at an oblique angle to cause the desirable presence of shadows in the field of view. The TV camera (16) outputs successive image frames so that displacement of a artifact in the image field in successive frames yields physical displacement information which is converted into velocity and direction information. Changes in position determined by the verification system are compared against position information maintained by the robotic arm (20); any mis-match indicates a loss of tracking integrity requiring a system re-calibration.