Army fielding is the process by
which new equipment is distributed to soldiers either at dispersed units at
homeland or at theatre of operations (J.D. Carter, SIEDS IEEE, 2007).
Minimization of personnel, space and time resources are of utmost importance
for improving the supply chain management system and the fielding of the
necessary equipment at the theatre of operations. The equipment is stored in
central warehouses where frequent and large orders of miscellaneous items are
received each day. The items have to be picked from specific location within
the warehoused then consolidated and finally dispatched. The most common type
of warehouse is divided into parallel aisles between multistore storage racks.
The order picking personnel walks or drives along the aisles to pick items from
storage. They can change aisles at a number of cross aisles, which are usually
located at the front and the back of the warehouse, but in some cases
additional cross aisles are located at positions in between. In this paper,
optimal routing of order pickers in parallel aisle warehouses is formulated as
a Travelling Salesman Problem (TSP). A Threshold Accepting meta-heuristic
algorithm is proposed next for the solution of the problem. The proposed method is tested on a large set
of randomly generated instances and is compared favourably to other methods
that can be found in the literature. Moreover, the proposed method is
implemented for the solution of a number of instances obtained during the
operation of a real warehouse. The method produces better results compared to
the method used in practice and it is shown that the warehouse operations can
be significantly benefited.