| Motion Control, a kind of Automatic Control technique, is an important component of Numerical Control (NC) technique. It's a precise method to control the position, velocity, acceleration and torque of the objects by digital signal. Because of the high calculation complexity of motion control, computers and control-cards have been used in most traditional motion control systems. In recent years, with the development of embedded system, more and more new micro controllers have appeared along with many advantages such as low cost, low power, high stability and real time characteristic, and they will take the place of computers to be the "heart" of NC systems gradually. A motion control system based on an embedded MCU is introduced in this thesis.This paper elaborates the principle of motion control systems. Based on analyzing of many software and hardware cases, a collective design of embedded pneumatic marker is given out as well as hardware configuration and way of realization. Besides, the paper describes the micro controller and peripheral circuits of the system, and discusses the algorithm of 3-axis motion control, then programs the algorithm and implements it on the hardware plat.The control system is uPSD3234A-40U6, which combines an 8032 micro-controller core, and expands some peripheral modules such as mass Flash memories and PLD (programmable logic device). This paper describes the memory organization, I/O ports, CPLD (complex PLD) module of the chip, then discusses the usage of the PSD soft Express software, which is used for set the chip.Data transmission between PC and this system is via USB interface. After the introduction of USB protocol, the paper discusses the usage of the general interface module USB20C, which used in the system. At last, give out a practicable communicate rule adapts to the requirement of this system, and then the high-speed and stabilized data transmission is realized.This system uses interpolation algorithm of comparison and integration to control the moving track of the cutter. After analysis of some common interpolation algorithm, principle of comparison and integration, and the programming flow of linear and circular interpolation, are expounded. Additionally, the disposal of some problem in practice, such as unified programming on four quadrants and error correction while interpolating, are also described.Besides, the thesis discusses some other issues, such as the power supply, some peripheral expander circuit, setting and connection of servo motor system. Finally, with the combination of all parts, an integrated project of pneumatic marker is constructed.Experiment proved that the collective design of the system is correct. According to the application requirements, many issues are considered in this project, such as performance figure, cost, anti-jamming capability, components layout, mechanical structure, electrical structure, and so on. While the system designing, the software and hardware have all been analyzed, demonstrated, tested, debugged and modified reiteratively, and pass the finial debug of the system, and achieve the anticipative design objective finally.This is a thesis for research and development, which serves for practical application. The design project not only adapts to a pneumatic marker, but also adapts to many other motion control systems, such as NC machine tools, robots, carving machines, plotters, and so on, and with high practical and generalized value. |
