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The aim of the work presented in this paper consists of the development of a decision-making support system, based on discrete-event simulation models, of an automobile assembly line which was implemented within an Arena simulation environment and focused at a very specific class of production lines with a four closed-loop network configuration. This layout system reflects one of the most common configurations of automobile assembly and preassembly lines formed by conveyors. The sum of the number of pallets on the intermediate buffers, remains constant, except for the fourth closed-loop, which depends on the four-door car ratio (x) implemented between the door disassembly and assembly stations of the car body. Some governing equations of the four closed-loops are not compatible with the capacities of several intermediate buffers for certain values of variable x. This incompatibility shows how the assembly line cannot operate in practice for x< 0,37 and for x>0,97 in a stationary regime, due to the starvation phenomenon or the failure of supply to the machines on the production line. We have evaluated the impact of the pallet numbers circulating on the first closed-loop on the performance of the production line, translated into the number of cars produced/hour, in order to improve the availability of the entire manufacturing system for any value of x. Until the present date, these facts have not been presented in specialized literature. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology for the evaluation of the performance of multistage multiproduct production lines, based on discrete-event simulation models, and developed in an Arena simulation environment. Its purpose is that of analysing blockage and starvation phenomena on a complex production line so as to assist in the decision-making process, since it allows for a greater understanding of the functioning of the production line. This is undertaken through the variation of different parameters, thus contributing to a better specification, characterization and definition of the most efficient planning and control system to be implemented in multistage multiproduct manufacturing processes. The methodology was validated by performing different simulation experiments and will be applied to a multistage multiproduct production line, based on a real case, with a closed-loop network configuration of machines and intermediate buffers consisting of conveyors, which is very common in the automobile sector. There are, in fact, very few studies undertaken which use simulation as a support tool in the decision-making process in the context of networks of closed-loop production lines. [ABSTRACT FROM AUTHOR]

Simulation is a technique which allows for the transfer of reality into the computer, through the creation of a model that reliably mirrors the behavior of a process (already existent or in its project phase). The work presented in this paper consists of the development of a decision-making support system, based on a real problem, with the purpose of optimizing the operation of an automobile assembly line with a four closed-loop network configuration. This layout system reflects one of the most common configurations of automobile assembly and preassembly lines formed by conveyors. A simulation model in an Arena environment was developed, which allowed for an analysis of the important aspects not yet studied in specialized literature, namely the assessment of the impact of the production sequence on the automobile assembly line. Various sequence rules were analyzed and the performance of each of the corresponding simulation models was registered. An experiment technique design was used in order to obtain the functions that describe the assembly system's behavior. [ABSTRACT FROM AUTHOR]