The Research Of Data Acquisition System For DNC Based On RS232

II Data acquisition is an important function of Distributed Numerical Control (DNC) systems. With the rapid development of manufacturing automation and enterprise information, it becomes more and more important that the data of manufacturing process is extracted, translated, processed, analyzed and applied. But most DNC systems in our country don't have the function of acquiring the status information of running machines automatically. It will be very meaningful to study and develop an advanced data acquisition system for DNC systems. An effective data acquisition system can help the enterprises exert the potential of their DNC systems, make the best use of the available resource, speed up automation and real time of the data acquisition.At first, this thesis has presented the current development and the trend of DNC data acquisition technology. Then researched on the analysis and comparison of the advantages and disadvantages as well as the application areas in the traditional DNC data acquisition methods. The data acquisition on FANUC, HAAS and SIEMENS NC systems using above methods also have been researched with macroinstruction and feedback of special NC programs methods. And successfully acquired NC status messages such as NC program number, federate, spindle speed, the processing start time of NC program, the processing end time of NC program, the item of processed parts and so on. The RS232 serial communication, the generation of acquisition programs, acquisition methods and the analysis of the data have also been discussed.In the thesis, the functions and databases of the DNC system are designed, and the DNC software system is developed. It has functions such as NC program transmission, drip feed, remote call, NC program management, data acquisition, log management and so on. The developed system has been tested in Engineering Training Center of NUAA. The essential functions of the DNC data acquisition have been realized.