Cycle time models for dual address storage and retrieval systems

Analytical models of order picking cycle times are proposed for storage and retrieval (S/R) systems using opportunistic and forced interleaving disciplines. For S/R systems using opportunistic interleaving, models are used to predict the distribution of single and dual command order picking cycles as a function of transaction demand and storage layout. For S/R systems using forced interleaving, models are proposed for estimation of expected system response times. In both cases, analytical methods are used to generate estimates of transaction service times, waiting times and order picker utilization