I. Introduction
The automation in manufacturing and supply chain management requires a large number of automated guided vehicles (AGVs) for handling the materials so that the smart warehouse or factories could be enabled [1], [2]. For example, many large companies like DHL, Walmart, and Amazon are using AGVs to facilitate their goods delivery and logistics operations [3]. However, most of the applications are used fixed lanes such as rail bound approach that is usually with high cost and low flexibility since the rails are based on steels and it is difficult to reconfigure when the warehouse layout is going to be changed [4], [5].