An investigation of internal logistics within a lean production system via simulation: A case study

Global competition has been forcing American organizations to seek new ways to become or remain competitive. The American 'golden era' of manufacturing has long past and with it many of the operations management techniques of mass production. This is particularly true of the automobile industry. The Big Three (GM, Ford, and Chrysler) have seen declining market share in the U.S. for the past few decades. Toyota is expected to become the leading U.S. automobile market share holder by the end of this year, which will be the first time in history that a foreign auto producer will have that title. Now many American firms, as well as foreign firms, have or have begun to adopt lean production systems in an attempt to achieve the same rewards that Toyota has reaped from its Toyota Production System (TPS).;Once a firm realizes that a change towards lean production will be beneficial, which is a difficult task in itself, it then faces many challenges to convert its current operations to that of lean standards. It took Toyota nearly three decades to perfect (or continuously improve) its operations to its current status which is world class. Many difficult challenges are to be faced by the organization that has a new vision of becoming lean, but by following benchmarks set by organizations like Toyota, the metamorphosis can take place much quicker with benefits acquired much quicker.;This research studies the internal logistics of a city-transit bus assembly plant. The assembly plant had implemented a lean production system recently and was still improving its operations with the goal of eliminating all waste from its operations. The objective of this research is to report internal logistics resource (kit carts) requirements for increased production rates and new kitting methodologies. The increased production rates were a recent benefit of the change to a lean production system as capacity had been freed up and the new kitting methodologies would further enhance the assembly systems leanness.;Since the assembly system of study is a rather complex system, simulation was chosen as the tool to complete the objectives of the study. The bus assembly system is considered complex due to the number of operations and internal-logistics associated with the large number of operations required for bus assembly at this plant. The simulation model is used to report internal-logistics resource requirements and thus benefits of new kitting methods. Rockwell Software's Arena was used as the discrete event simulation tool for this study. The results of the simulation study were used to provide management at the bus assembly plant resource requirement figures for a combination of increased production rates and several kitting methodologies. These resource requirement (kit cart) figures can be referenced for different stages of improvement to overall internal-logistics.