An Efficient Multi-AMR Control Framework for Parcel Sorting Centers

Abstract

With the growth of eCommerce activities, there is an urgent need for robust logistics solutions to ensure mass and speedy parcel delivery. Upon the parcels are collected, one of the main issues is how to sort a large number of parcels efficiently. One of the solutions is to automate the sorting process in sorting centers by using autonomous mobile robots (AMRs). This paper investigates this solution and studies the multi-AMR control framework for automated parcel sorting centers. In the literature, various frameworks have been proposed for controlling multiple mobile robots under different scenarios. However, most of these existing frameworks may not be well-suited to the automated sorting center environment because the automated sorting center might contain a considerable number of robots moving at high speed. Thus, the routing decision of each robot and the traffic control would need to be done in real-time in order to alleviate congestion to increase the throughput. In this paper, an efficient framework is proposed for automated sorting centers in order to support many high-speed robots. In particular, the proposed framework uses two-layer hierarchical architecture, where all AMRs are considered as the clients of a centralized server. However, unlike traditional server/client architecture, the decision modules in the proposed framework are distributed between the server and clients. Such a design can shift some computationally expensive algorithms from the server-side to the client-side, and thus it is more scalable. The simulation results show that the proposed framework can achieve excellent results. For example, in a sorting center with an area of 2025m2, 410 robots are deployed, and they can handle nearly 30,000 parcels in an hour with our proposed framework. Finally, this paper also explores the various possibilities to enhance the framework further.