Research On MES Based Scheduling System For Cable Manufacturing Shop Floor

A great variety of product specifications, separate and discontinuous manufacturing procedures, long production cycle and uncertainty of semi-finished articles flow are the typical characteristics of cable manufacturer. As one of the most critical factors, the solution of job scheduling problem will affect the running efficiency of shop floor. With the rapid accumulation of production information and the increasing complexity and diversity of manufacturing system, the conventional way of information transfer, data acquisition and statistic can not fulfill the requirement of shop floor scheduling, therefore, it is essential to research into and practise the information management of cable manufacturing.Aiming at the characteristics of cable manufacturing, A three-hierarchy architecture information system composed of ERP(Enterprise Resource Planning),MES(Manufacturing Execution System) and PCS(Process Control System) is proposed, in which MES is responsible for the central manufacturing information management as the interface between ERP and PCS. This architecture provides solutions for the problems in production scheduling, process control and quality control in cable manufacturing and leads to the objectives of custom-oriented, length-determined and deadline-met manufacturing.In order to solve the problem of real-time and dynamic scheduling in MES, a heuristic algorithm, based on bottleneck analysis, is proposed. This algorithm derives from the idea of OPT(Optimized Production Technology) and SBH(Shifting Bottleneck Heuristic). In this algorithm, the methods of bottleneck definition are presented; the bottleneck analysis based scheduling mechanism is expounded with the serial line sub system and the assembly line sub system. And the scheduling algorithm is applied and evaluated in the cable manufacturing system. A real-time database and a statistic database are established on server; the communication mechanism of Thin Client/Server system architecture is analyzed systematically. A monitoring and scheduling system for cable manufacturing shop floor is designed and developed for the information integration of job scheduling, process monitoring and quality control. The main functions of the system include: acquisition of daily production plan, management of shop floor manufacturing resources; job scheduling; process monitoring; on-line statistic of production information; information transfer and database sharing among scheduling terminal and process terminals.A simulation model for the monitoring and scheduling system is established, in order to analyze the existing shop floor problems, validate and optimize the scheduling algorithm. An emulation environment for the monitoring and scheduling prototype system is established, in order to test the running performances of the monitoring and scheduling system and the database capabilities of mass storage and multi-route dynamic input and output. The simulating and the emulating results demonstrate that the scheduling algorithm can fulfill the requirements of the cable manufacturing job scheduling against feasibility, dynamics and real-time performance. It has considerable and promising future of social and economic benefit.