Vehicle interference effects in warehousing systems with autonomous vehicles

Autonomous vehicle based storage and retrieval (AVS/R) systems offer greater flexibility to improve cycle time and throughout capacity in the transfer of unit loads in high density storage areas. AVS/R systems rely on autonomous vehicles to provide horizontal the movement within a tier and use lifts to provide vertical movement between tiers. In these systems, vehicle interference in the aisles and cross aisles could significantly decrease system throughput and increase cycle times. In this research, protocols are developed to address vehicle interference and a queuing model is proposed to analyze system performance. A decomposition-based method is used to solve the model and quantify the effect of interference. The interference effects are studied for systems with varying tier configuration parameters such as depth/width ratio and number of vehicles. These insights are validated against detailed simulations.