Improved tip tracking for an industrial robot using Iterative Learning Control

The laser welding process puts high demands on the manipulator that moves the laser beam with respect to the weld seam. Typically an accuracy of about 0.1 mm is required at speeds beyond 100 mm/s. From an industrial perspective the use of six-axes industrial robots is attractive as these can access complex three dimensional seam geometries. However, using standard industrial controllers the tracking accuracy of these robots is insufficient for laser welding