The application of lognormal models of transient operations in the flexible manufacturing environment

Abstract Fundamental aspects of models that might be used to design and/or manage operations in the flexible manufacturing environment are presented in this paper and demonstrated in hypothetical, but typical, examples. Applications suggest use to coordinate production and assembly operations so that lots are completed as scheduled with minimal levels of in-process inventory. Specific examples include coordinating the delivery of components required to assemble a product, analyzing the throughput and productivity of a robotic cell, and managing the flow of materials amongst cells. Numerical tests in these contexts indicate that the modeling approach, which approximates transient (as well as steady state) operations, gives results that compare favorably with those derived from a simulation model at a substantial runtime advantage. The approach appears to offer a viable means of conceptualizing transient operations and is supported by empirical justification.