The Design And Research Of Motion Controller Based On DSP

In this thesis, the author firstly introduces the technology of gravure which is widely used at home and abroad. Gravure process printing control system is an important part of packing printing machine, which takes charge of exact positioning control of every color, and plays an important part in the printing quality. With the rapid development of packing printing technology, there are more and more high request to automation and position tracking accuracy of packing printing transmission system. Now the controller of high speed packing printing machine in the domestic market, which control precision and automation degree is high, mostly is overseas product. But the controller's price is also too expensive to afford for the common enterprise. It's very important and practically significant to develop high-powered and low-pricing automatic control system of the packing printing machine. The system has high performance and low price.Motion Controller (MC) is a control device that regards its central logic unit as the core, sensor as the sensitive component, and electromotor or executive unit as the controlled object. As the core of an automatic process printing control system, MC should not only have high-grade control precision and high computing speed, but also have generality, so as to expand, improve and maintain easily and hence to constitute an open control system. MC based on single chip microcomputer has not met the requirement of complex and advanced algorithms; the special motion control chip designs easily but expand hard and the computing speed is lower. During the research, through the overall survey of the open numerical control system and deep study of motion control technology, to meet the practical requirements of the gravure control system, adopting the solution based on DSP and FPGA, the author develops a MC to control the motor so as to improve the precision and the press speed of the printer, in which DSP is the core of dealing with advanced algorithms and FPGA is the coprocessor achieving modularity tasks. Thus, this system is more flexible, more efficiency and more useful. Furthermore, it costs less time to update and expand, maintain easily. The author firstly introduces the background and the significance of the research, current related technology status and main research contents. Then it introduces the composing and the work principle of the system, and carries on research on automatic process printing control system. A control and realization method of automatic register controller for gravure printing is presented. This control system uses two-photoelectric-sensor and the incremental optical-electrical encoder to capture the printing error. The author introduces in details the whole blue print of the system, discusses the design of the hardware and software system according to the blue print, then demonstrates and simulates the control algorithm. Finally, it gives discussion on the system debugging and gives the summing-up result report of the system, proves its feasibility, and comes out the content that needing mending.The system includes the user interface and the local control unit. As the core of the system, the user interface connects the control unit with the bus and monitors the whole operation of the system. It achieves initialization, proof before printing, parameter setting, waveform displaying, state displaying and so on. Control unit which is the basic unit of the system is a self-governed relatively module. In the control unit, local micro-controller controls color register procedure and transmits data with the user interface. Photoelectric detector and photoelectric encoder detect the error. The local color register unit is emphatically researched, which adopts servo system controlled by MC achieving its function.Based on the technology of DSP and FPGA, the paper has completely improved the bottom hardware structure of MC and realized the bottom motion control unit and the peripheral process unit. The paper has built a high-capability hardware platform for MC, which has expanded multi-function modules, such as DAC and external memorizer, and multi-communication interfaces, such as PCI, CAN, and RS232. The controller regards the special motor control chip, 16-bit fixed-point DSP TMS320LF2407A including the capacity of high-speed calculation and motor control which TI Company supplied as the key chip. The paper gives the design of peripheral circuit, including the interface circuit for serial communication between DSP and the upper PC, the circuit of DSP extended-memory and the voltage transforming circuit. And the paper summarizes some noticeable problems in the system design. According to the characteristic of position feedback signal processing, the FPGA chip instead of the isolated component is adopted to process the position feedback signal. And the performance in logic and electric has been greatly improved. The author do the simulation by the software of Max+plusⅡand do the emulation on the FPGA developmental board based on EP1K30QC208, and get the satisfied result.The hardware of the controller is divided into bus interface module, signal process module, D/A transform module, feedback input module and expand I/O module. The bus interface module is used to communicate with the host. The signal process module is employed to achieve the control arithmetic and to transform the motion control instruction into the digital signal of motor controlling. The D/A transform module is employed to transform the digital signal into the analog signal for achieving the better motor motion character. The feedback module receives the feedback signal from the encoder, and achieves position servo-control. The expand I/O module is used to send the enable signal to the driver or receive the false signal from the driver.The subject has finished the whole hardware design, and has finished the composition of the software system, including the initialization of DSP, setting up multitask, preliminary composition of each function module, has finished the hardware test job in Compile-language and C-language under Code Composer Studio (CCS) environment of TI. The software design method of DSP MC is investigated. Through the program used for the servo control, it analyzes the processing of feedback signal from the incremental encoder, the implementing of serial communication and position control. The real time requirement of motion control is realized by using time cycle and priority scheduling method. Simultaneously, the digital PID algorithms are used in the local color register control, the local color register control algorithms are brought forward and simulated by MATLAB. On the basis of the above-mentioned achievements and interrelated theory, the hardware and software debugging has been accomplished to validate the correctness of hardware circuit and software which have made the anticipated result.