【正文】 part or product. Flexible manufacturing fills this longstanding void in manufacturing. Flexible manufacturing, with its ground capabilities, offers a number of advantages for manufacturers: 4 * Flexibility within a family of parts * Random feeding of parts * Simultaneous production of different parts * Decreased setup time and lead time * More efficient machine usage * Decreased direct and indirect labor costs * Ability to handle different materials * Ability to continue some production if one machine breaks down 3 Flexible Manufacturing System Components An FMS has four major ponents: * Machine tools * Control system * Materials handling system *Human operators (1) Machine Tools A flexible manufacturing system uses the same types of machine tools as any other manufacturing system, be it automated or manually operated. These include lathes, mills, drills, saws, and so on. The type of machine tools actually included in an FMS depends on the setting in which the machine will be used. Some FMS are designed to meet a specific, welldefined need. In these cases the machine tools included in the system will be only those necessary for the planned operations. Such a system would be known as a dedicated system. In a jobshop setting, or any other setting in which the actual application is not known ahead of time or must necessarily include a wide range of possibilities, machines capable of performing at least the standard manufacturing operations would be include. Such systems are known as general purpose systems. (2) Control System The control system for an FMS serves a number of different control functions for system: * Storage and distribution of parts programs * Work flow control and monitoring * Production control *System/tool control/monitoring The control area with the puter running the FMS control system is the center from which all activities in the FMS are controlled and monitored. The FMS control software is 5 rather plicated and sophisticated since it has to carry out many different tasks simultaneously. Despite the considerable research that has been carried out in this area, there is no general answer to designing the functions and architecture of FMS software. The scheduler function involves planning how to produce the current volume of orders in the FMS, considering the current status of machine tools, workinprocess, tooling, and so on. The scheduling can be done automatically or can be assisted by an operator. Most FMS control systems bine automatic and manual scheduling。 the system generates an initial schedule that can be changed manually by the operator. The dispatcher function involves carrying out the schedule and coordinating the activities on the shop floor, that is, deciding when and where to transport a pallet, when to start a process on a machining center, and so on. The monitor function is concerned with monitoring work progress, machine status, alarm messages, and so on , and providing input to the scheduler and dispatcher as well as generating various production reports and alarm messages. A transport control module manages the transportation of parts and palettes within the system. Having an AGV system