The production planning problems of flexible manufacturing systems with high tool variety
This research is concerned with certain production planning problems associated with flexible manufacturing systems (FMS) with high tool variety. In this environment of FMS, the tool requirements at workstations exceed the respective tool magazine capacities. During an extensive survey of related literature, it appeared that the problems associated with this type of FMS have been overlooked by the FMS research community. The operational problems of FMS are discussed with special reference to the constraints imposed by tooling. The characteristics of the selected FMS type are clearly defined. This discussion is supplemented with a detailed description of a real FMS which resembles the operations of the selected type of FMS. Having identified certain drawbacks of some existing simulation software, the development of a comprehensive FMS simulator which uses a novel hybrid modelling technique is discussed. The use of a graphical post-processor which can be used to enhance the system logic of the FMS is also described number of parameters associated with the tool management system are identified and the methods are described to evaluate these parameters. The importance of evaluating these parameters in design and operation of an FMS is stressed. The development of a tool post-processor which can assist in identifying the scale of the tooling problem and in evaluating tool management parameters is presented. A variety of tool availability strategies which reduce the tool exchange rates are suggested and evaluated. Finally, the part selection (for immediate processing) problem is solved using a novel technique which takes the advantage of the availability of real time data in FMS.