The case in the gripperCases: 600 × 400 × 300 mm, six to a layerLaser line: the camera's height profile of the stackCases roll in at 0.5 m/s and stop against the plate; the photo-eye sees each arrive. The arm lifts it on six vacuum cups and swings it to the pallet while the camera on the mast sweeps a laser line across the stack. The height profile tells the controller which slot is free and how high to set the case down. Even layers lie long along one edge and odd layers turn 90°, so every seam is bridged by the case above it. Inside a layer the far slots are filled first, so the arm never reaches over a case it has already placed. One case every 5.8 s; 24 cases make a 1.34 m stack.