An optimisation Model for minimising Totes exchange in VLM and SBS/RS integrated System

Warehouses and distribution centres are based on integrated material handling solutions. Most of the research papers in intralogistics are only concerned with one system to analyse and optimise the addressed system's performance, such as maximum throughput performance, minimum total cost, maximum energy efficiency, etc. This paper presents a concept to justify the proposed VLM and SBS/RS integrated system and a binary integer programming (BIP) model that minimises totes exchange between the two storage systems. The results show that the minimal number of exchanges between VLM and SBS/RS was achieved in a case study with a longer order list (T = 1600) and a highly dependent SKU's Pareto relationship (20-50).