Research On Several Key Technologies In Manufacturing Execution System (MES)

The global economic development shows that a country's power mainly depends on its manufacturing's capacity to manufacture products and provide service. The workshop is the basic link of a manufacturing chain, the connection of management and manufacture and the joint of information streams and material streams. It is an urgent task for Chinese manufacturing to employ information technology and up-to-date management ideas in production organization so as to improve their competitive power.Manufacturing Execution System (MES) is the application of the up-to-date information technology in workshop management. It is the workshop-oriented production control information system between the plan system and the control system. Starting with the analysis of technology actualities and trend in the development of MES, this thesis is aimed at solving the bottle-neck problems in MES which block the development of workshop production control system and focuses on several key technologies in MES. The main contents are as follows:1) This thesis develops a new modeling method of material process state for enterprises to make the real-time rolling production plan. By defining material process state vector, the material process state is described accurately with the value corresponding to the vector. In this way, an unfinished process can be described precisely. This new method makes it possible that the unfinished procedure is rearranged into a new production plan. It ensures the real-time and accurate workshop production plan rearrangement;2) Considering the static BOM(Bill of material) can not be on the real-time and accurate track of the dynamic material machining process, a dynamic MBOM (Manufacturing bill of material)model is made, which links material, material procedure, material process state, processing time and manufacturing resources closely. This model makes the accurate location of the in-process material possible and provides an effective theoretical model for the real-time and accurate track of materials;3) In view of the manufacture of multi-model products, the randomicity of workshop environment and the fuzziness of the processing time and the due-time and based on product assembly kitting, this thesis develops an optimal scheme of job shop schedule, which is aimed at the highest satisfaction degree of all the customers. In addition, aimed at solving the problem of parallel machines and procedures in job shopschedule, schedule rules are set and thu.s ihe flexibility of job shop schedule isensured:4) To ensure the integrality, accuracy and consistency of the data in the information integration process of MES, the plan system and the control system, a skeletal model supporting information integration is made. By analyzing the features of BOM, a BOM transformation method based on feature identification and a data mapping model of BOM transformation are presented. Besides, considering the assembly attributes and natural attributes of EBOM (Engineering bill of materials) differ from those of MBOM, transformation rules are set and thus automatic transformation from EBOM into MBOM is achieved and the theoretical foundation of information integration is laid.