Simulation-based time-efficient and energy-efficient performance analysis of an overhead robotic compact storage and retrieval system

Abstract

This paper evaluates an overhead robotic compact storage and retrieval system (ORCSRS), which is a novel automated compact system where basic storage and handling containers are stacked on top of one another to form bin stacks on each plane. Bin-picking robots and track-changing robots are assigned to carry bins with the target stock keeping units (SKUs) to the picker to fulfill orders. We develop a discrete event simulation model to analyze the performance of an ORCSRS in terms of efficiency and energy consumption. Performance indicators such as throughput, robot utilization, and system energy consumption are obtained for both single-SKU and multi-SKUs cases and both dedicated and shared storage policies coupled with random and zoned stacks. Our results provide valuable suggestions for the optimal design of an ORCSRS, such as the best layout for optimizing throughput, number of robots required to achieve a given throughput in a limited warehouse area, and the maximum number of bins that should be stored in one stack.