Automatic Storage/Retrieval Systems (AS/RS)

AS/RS consists of an integrated computer-controlled system that merges the storage medium, transport mechanism, and controls with various levels of automation for high-speed and precise random storage of products and materials. AS/RS minimizes required manpower and floor space while maximizing the cubic utilization of existing height of warehouse.

Storage/retrieval (S/R) machine in an AS/RS operates in narrow aisle, serving rack slots on both sides of the aisle. It can travel in horizontal (along the aisle) and vertical (up and down a rack) directions concurrently.

The benefits of AS/RS are manpower savings, better material control and security, and increased cubic utilization rate. On the other hand, the limitations of AS/RS are high capital and maintenance costs, as well as modifications are made difficult.

(a) Unit Load AS/RS

• Used to store/retrieve loads that are palletized or unitized and weigh over 500 lbs
• Loads can stack up to heights of 130 ft. high, with most ranging from 60 to 85 ft. high; 5 to 6 ft. wide aisles; single- or double-deep storage racks

(b) Mini Load AS/RS

• Used to store small parts and tools that can be stored in a storage bin or drawer
• End-of-aisle order picking and replenishment
• Stacking heights range from 12 to 20 ft.; bin capacities range from 200 to 750 lbs
• Termed a "microload AS/RS" in assembly, kitting, and testing operations to deliver small containers of parts to individual terminals, where terminals are typically located on the sides of a pair of racks and the S/R machine operates between the racks to move containers to openings in the racks (storage lanes) located next to each station

(c) Man-On-Board AS/RS

• Used for in-aisle picking; operator picks from shelves, bins, or drawers within the storage structure
• Manual or automatic control S/R machine is akin to an order picker or turret truck and can sometimes operate as an industrial truck when outside an aisle, except the S/R is guided along a rail when operating in an aisle

(d) Deep-Lane AS/RS

• Similar to unit load AS/RS, except that loads can be stored to greater depths
• A rack-entry vehicle is used to carry loads into the racks from the S/R machine, and is controlled by the S/R machine
• Known as an "automated item retrieval system" when automatically retrieve individual items or cases, with replenishment (storage) taking place manually from the rear of a flow-through storage lane and items are pushed forward with a rear-mounted pusher bar for automatic picking from the front of the storage lane

Material Handling Equipment
Storage Equipment