An Improved Ant Colony Algorithm for Order Picking Optimization Problem in Automated Warehouse

Automated storage and retrieval system (AS/RS) is being widely used in the logistics industry. The order picking problem is researched to improve the overall efficiency of the system. A mathematical model is constructed to obtain the minimal travel time during the retrieval and storage operation under the operating condition that each machine serves several aisles of the system. The aisles are assumed to exist in the same region of the AS/RS and thus form a valid order S/R zone. An improved ant colony algorithm with awaiting node set, dynamic change on algorithm parameters and selection operator is developed for searching the optimal solution. Simulation results demonstrate the approach has better search ability and quickly astringency, satisfying the demands of medium or large scale work in AS/RA. The approach is an effective solution to order picking problem in automated warehouse.