Cnc Engraving Machine Controller Based On Embedded Technology Design And Development,

Industrial control computer and motion control card is usually used in numerical control engraving machine at present. This solution was caused high cost, large volume, low reliability and flexibility etc. As the fast development of embedded technology and application, it has also become a research focus in the NC engraving industry recently. A NC engraving machine controller was designed and developed based on embedded technology in this thesis. Its hardware and software architecture are concision and compact. At the same time, its cost is lower, volume is smaller, reliability and flexibility was promoted, easy to maintain and upgrade.Current situation of NC engraving machine and appropriate control technology at home and abroad were analyzed. The control methods of NC engraving machine was studied and improved. So, a digital differential analyzer linear interpolation and speed control method for small line blocks were obtained. According to the requirements of NC engraving controller, the overall design scheme of the controller was made based on embedded technology. In the hardware design, ARM9+FPGA architecture was used. ARM9 is the main processor which is used to run embedded operating systems and graphical interface, as well as large amounts of data processing algorithms. FPGA is as coprocessor which is mainly used to control pulse. The controller hardware schematic diagram was designed in detail. Then PCB layout was also completed.As the complexity of embedded system application increasing, software development of embedded system is also becoming more and more complex. Traditional process-oriented analysis and developing methods have been not suited. So an iterative incremental embedded software development process was used which combined object-oriented Unified Modeling Language and process-oriented DARTS method. It was started from the controller requirement description. Then use case model, problem domain static model and system context class diagram were established. After that, external class and interface class were determined by using object construction criterion. The data flow diagram in DARTS method was used to analyze system internal objects. Data processing in the DFD can often be seen as algorithm object and the storage of data can be seen as entity object. Collaboration diagram and state diagram were established through iterative analysis of the above two methods. Then, class design was made on the basis of these diagrams. Embedded Linux was transplanted and customized to the ARM9 as software development platform in the implementation stage. Qtopia was used as the controller graphic user interface based on embedded Linux. It is object-oriented language-C++ development tool. So the object model can be realized smoothly. Multi-thread was designed and real-time task was also analyzed in the application. It was obtained good results through practically engraving. The controller has been produced in a small batch by a company.