MATERIALS HANDLING SYSTEM DESIGN - Environmentally Conscious Materials Handling - page 28

to guarantee the performance to the customer by selecting the best equipment
and a global management of the entire project.
Savoye Logistics has introduced the AVS/RS shown in Figure 1.16. The system
has been successfully installed in 35 companies in Europe. Today, the installed
systems' capacities are around 1,000,000 pallets and 100,000 movements per
day, in eight countries.
Figures 1.17a to 1.17c illustrate the two components of the AVS/RS, one of
which is autonomous vehicle and the other is the lift. Although the autonomous
vehicle moves horizontally in the storage areas in a given tier, the lift moves
the vehicle between tiers. In other words, autonomous vehicles move on rails
in the aisles and interface with lifts for vertical movement of pallets between
storage tiers. Here, lifts are like conveyors, but they can travel only vertically.
Autonomous vehicles also transport pallets between lifts and shipping/receiving
areas at the ground level. They can transform the loads from their stored areas
to their respective storage addresses in the same tier because they can move
within tiers. If the load movement is not on the same tier, then lifts are used for
transferring the load to the related tier.
The different load movement patterns make AVS/RSs more flexible than AS/R
systems, although at slightly lower efficiency. In AS/RSs, aisle-captive cranes are
the main S/R devices to move unit loads simultaneously in the horizontal and
vertical dimensions. Unlike storage cranes in AS/RS, AVS/RS vehicles can access
any designated storage address but must move in a sequential, rectilinear pattern.
One of Savoye Logistics' AVS/RS applications completed in 1999 was for a
telecommunication company that faced rapid growth in one of its warehouses.
The logistical challenge in planning was to link the technological manufacturing
levels of two buildings with a production supply chain to sustain the material
flow from the assembly lines to dispatch. The AVS/RS designed by Savoye was
able to satisfy these constructional requirements with a supply and unloading
line offset at an angle of 90 degrees. The system has now been in operation and
fulfils the short lead times and safety requirements and can achieve fill rate of
95 percent.

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