Patent ID: 8882432

Claim:
A method comprising: moving a three-dimensional robotic automated storage and retrieval system in a vertical direction to a first position; loading items from a rack at the first position onto the three-dimensional robotic automated storage and retrieval system; moving the three-dimensional robotic automated storage and retrieval system in a horizontal direction to a second position; loading items from the rack at the second position onto the three-dimensional robotic automated storage and retrieval system; wherein the three-dimensional robotic automated storage and retrieval system includes a carriage, a robot arm, a vertical lift mechanism, and a horizontal propulsion system, wherein the carriage has a length that is shorter than the length of the rack, wherein said moving the three-dimensional robotic automated storage and retrieval system in the vertical direction includes moving the carriage vertically with the vertical lift mechanism; wherein said loading items from the rack at the first position includes palletizing the items with the robot arm; wherein said moving the three-dimensional robotic automated storage and retrieval system in the horizontal direction includes moving the carriage horizontally along a rack aisle with the horizontal propulsion system; and wherein the carriage is secured at a horizontally fixed position relative to the vertical lift mechanism so that the carriage is unable to move horizontally relative to the vertical lift mechanism.