自动化立体车库管理系统的设计(英文文献+CAD图纸) 第12页

自动化立体车库管理系统的研究(英文文献+CAD图纸)
messages) means the operation for resetting the milling machine.
 5.3. Management of resource data
The management of resources in the FrMS is modeled by using a use-case diagram of UML as illustrated in Fig. 12. A use-case can be described as a specific way of using the system from a user’s perspective. A use-case diagram contains actors, use cases, and interactions or relationships between actors and use cases. Types of interactions include associations, dependencies, and generalizations.
The agent called FSM manages information about the resources. If a fractal becomes an equipment controller, the FSM manages equipment status while dealing with equipment commands or signals as well as fractal status. In addition to the FSM, the following agents are also related to the equipment: (1) FAM, (2) NTA, (3) STA, (4) EMA, and (5) ECA. The EMA receives signals from equipment through the RS-232/422 protocol or an equipment interface that connects directly to the equipment from the equipment controller. The ECA sends equipment commands to the equipment in the same way as the EMA. The FAM manages equipment addresses such as the numbers corresponding to serial ports which indicate speci?c equipment connected to the controller. The NTA manages the addresses of the unassigned controllers (fractals) that could be used as a controller in the system, and the STA manages the speci?cation of controllers that are currently working in the system.
The FSM manages the following information that constitutes a fractal’s status:
Hierarchical position of the fractal: Fractals are normally classified into hierarchical levels such as top, intermediate, and bottom. If a fractal belongs to the top-level, it naturally does not have any information about the fractal in the level above it; in other words, it has a null character in the address field for the upper-level fractal. A fractal belonging to an intermediate level has information about both its upper-level and sub-level fractals. A bottom-level fractal does not have any sub-fractals and is directly connectedtoequipment. It alsohasa null
   character in the address field for the sub-level fractals in FAM. Information about controlling equipment: In fact, a fractal in any level in the hierarchy can control equipment. If a fractal is directly connected to and controls equipment, it has to manage information about the equipment. In such cases, the FAM keeps and manages the equipment address, and the FSM monitors the equipment status (e.g. busy, idle, or non-operational).
  Information about currently processing jobs: The FSM manages information about the current work being processed according to job profiles or job schedules. It monitors and manages information about
 Fig. 12. Use-case diagram for managing resources in the FrMS.
all of the jobs that have been or are being processed in the fractal.
Product information: When a fractal controls machine equipment (e.g. machining center, lathe, and milling machine), it has to deal with a product. In that case, the FSM manages product information.
 5.4. Management of product data
The product class is created and managed by the FSM in the FrMS. The attributes of the product class include (1) product_id, (2) priority, (3) processing status, and (4) time information such as arrival time, desired release time, expected machining time, and due date. Normally, the fractals (bottom-level fractals) that control equipment have detailed information about products, while upper-level fractals manage abstracted information. For example, a bottom-level fractal manages all of the aforementioned information about the product in the course of processing jobs, whereas a top-level fractal keeps only abstract information about the product such as product_ids, the number of products, and references to product classes. Information in a product class is passed to another fractal along with the movement of a physical

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