Embedded Platforms Based On The Three-dimensional High-speed CNC Engraving Machine Control System Design And Implementation

With the improvement of science and technology, the technology of numerical control and mechatronics system had gotten rapid development. As the typical representative of mechatronics system, the numerical controller of engraving machine is one of the basic equipments based on modern science and manufacture system, whereas, the homemade numerical controller of engraving machine usually have bad cost performance, and it is becoming one of the disadvantages to decrease its competitiveness. So, one numerical control system of three-axis high speed engraving machine was proposed in this paper, ARM9 and FPGA was set as the core of the controller, and the requirements of industrial production were also considered in the design process, so that this controller could strengthen the competitiveness of homemade engraving machine by good cost performance.In this paper, the numerical control technology and embedded system were connected, 32 bit ARM9 micro processor and FPGA were combined to instead of the group of single chip microcontroller and industrial computer (IC) as the core of controller, Windows CE operation system was selected as the platform, the speed and trace of engrave was controlled by ARM while the drive pulse was sent by FPGA. The control system could get rid of the dependence on IC and complete the whole work which start from reading original data to the end in outputting control signal.Through the pretreatment of the processing track, the contradiction between over cuting engrave and frequent acceleration and declaration of the stepping motor was solved, which not only guaranteed the high speed and the continuance in the engraving process but also avoided the bump to the stepping motor and machine tool due to the change of trace direction and the jump of the speed.In the speed control, through the combination of the torque-frequency peculiarity of stepping motor and the calculation capacity of the microprocessor, using several lines to imitate the exponential curve for speed control was proposed, so that the resources of MCU was utilized reasonably and the speed of motor was smooth. In the track control, the high speed DDA interpolation algorithm was used as the improvement of the normal DDA, so that the operation efficiency of the interpolation was raised which reduced the operation pressure of the controller.This control system was put into practice to fulfill the engraving experiment. With friendly HCI and powerful awxiliary function, this system, which is also compatible with the common used G-code and HPGL-code, was able to fulfill those complex engraving such as for decorations, scutcheon and so on.The practical application results validates this numerical control system of three-axis high speed engraving machine based on embedded system is reliable and feasible, and also proved to have much value in application.