In this article, we investigate a two-tier delivery network with robots operating on the second tier. We determine the optimal number of local robot hubs as well as the optimal number of robots to service all customers and compare the resulting operational cost to conventional truck-based deliveries. Based on the well-known p-median problem, we present mixed-integer programs that consider the limited range of robots due to battery size. Compared with conventional truck-based deliveries, robot-based deliveries can save about 70% of operational cost and even more, up to 90%, for instances with customer time windows.

中文翻译：

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基于机器人交付的两层城市交付网络

在本文中，我们研究了一个两层交付网络，机器人在第二层上运行。我们确定本地机器人中心的最佳数量以及为所有客户提供服务的最佳机器人数量，并将由此产生的运营成本与传统的基于卡车的交付进行比较。基于众所周知的p 中值问题，我们提出了混合整数程序，该程序考虑了由于电池尺寸而导致的机器人范围有限。与传统的基于卡车的交付相比，基于机器人的交付可以节省约 70% 的运营成本，甚至更多，高达 90%，例如有客户时间窗口。