Universal Robots UR5 User Manual page 179

14.26 Command: Seek
Stacking
When stacking, the robot arm moves to the starting position, and then moves op-
posite the direction to search for the next stack position. When found, the robot
remembers the position and performs the special sequence. The next time round,
the robot starts the search from the remembered position incremented by the item
thickness along the direction. The stacking is finished when the stack hight is more
than some defined number, or when a sensor gives a signal.
Version 3.4.5 II-97 CB3