Research Development Information Retrieval System Of STEP-NC Workpiece Programme Based On SDAI

As a new standard of CNC system, STEP-NC provides a neuter mechanism. Its universal data access standards eliminate the problems of NC enclosure and uninterchangeability, and wipe off the fussy aftertreatment system of CAM; It improves the transferability of NC and the flexibility of the whole system; It supplies the data bidirectional transmission, and makes the join monolithically between CAD/CAM/CNC come true, accordingly it's a great convenience to information communication and sharing between systems, and at the same time, lays the foundation of advanced production mode, such as concurrent engineerings agility manufacture and internet manufacture. Since having all of these traits, the NC technology based on STEP-NC can syncretize more computer technology, internet technology, information technology , artificial intelligence technology, and so on.. STEP-NC will smarten the space of NC's development to open type, latticing, intelligentize and high precision and speed. First laid in the project ESPRIT IV 29708 of EC in 1997, Europe , America, Switzerland and Korea start the research plans one after another, includes three aspects: developing the STEP-NC data modal and establishing the standards, developing the NC prototyping system based on STEP-NC and developing information compositive design manufacture organization based on STEP-NC. As a result, from the traits of STEP-NC, it has the important actual effecting and application value to study the pivotal technology of STEP-NC.The paper mostly includes the research development of STEP-NC information picking up system based on SDAI, the system is prepared for developing the STEP-NC system. This paper has six chapters. Chapter one introduce the state and trend of NC development at home and abroad, and then gave a summary of the STEP-NC development and virtues comparing with the traditional G, M code, giving the significance and contents of study at last. Chapter two introduce the pivotal support technology, includes STEP and STEP-NC, operating principle and structure of SDAI, EXPRESS language and OpenGL technology. Chapter three firstly analyze the frame traits of STEP-NC procedure and the meaning of character in the procedure, and then give some data structure defined in the lexical analysis and processing methods, finally present the implement process. Chapter four set up the data structure of module and access after interpreting the function module of SDAI, then bring the data management mode and mechanism, and establish the data stream modal, in the end of this chapter, give the process of distilling entity-instance. Chapter five is main about the realization of software system. First, introducing the whole structure of this system and key implement technology. Then, give a demonstration with example from STEP-NC criterion, and display the machining information, and display the three-dimension modal of the example using OpenGL technology. The last chapter summarizes the study process and expects the development of correlation technology.