order picking process: state-of-the-art on classification

An order-picking system (ops) is essential to meet customer needs and orders in inbound logistics. failure to perform the process properly results in high costs and customer dissatisfaction. to properly execute the ops and to be able to meet the needs of customers with maximum efficiency, different aspects of the order picking process should be carefully considered. research works have been conducted to improve ops. this article attempted to review study components, study methods, and results in internal logistics while focusing on ops. we also examined the composition of different aspects of ops, including cost, equipment, warehousing, assignment, routing, batching, sequencing, and tardiness in 157 articles performed from 1958 to 2020 and studies on the process of time (makespan). the reviewed studies were classified based on the simultaneous use of batching variables, assignment, routing, sequencing, and tardiness, the methods used in the research work, and finding research gaps for future investigations to clarify the relevance and application of routing, assignment, batching, sequencing, and tardiness aspects in the order picking process.