The Monitoring System Of Shaftless Gravure Press Based On CAN-Ethernet Gateway

Along with the rapid development of the computer technology, industrial Ethernet technology and fieldbus technology, the shaftless driving technology is introduced into color register industry, and is fast becoming the mainstream driving mode of modern printing machine.The color register monitoring system of shaftless gravure press is taken as the subject in this thesis, so we design a new-type of CAN-Ethernet gateway and propose the hardware design scheme of gateway which centres on the F28335 DSP chip and external extends the DM9000 A network chip and the CAN transceiver controller chip. By adopting the distributed control scheme on monitoring system, the parameters of each color register plant unit are transmitted to the communication gateway in real-time by using CAN bus.Then the gateway realizes the conversion between CANopen protocol frames and Modbus/TCP protocol frames, eventually the parameters are transmitted to the main monitoring human-machine interface through the Ethernet. So as to realize the communication between the control unit box of color register and HMI, it is convenient for users to do remote debugging and real-time monitoring of the printing field. In addition, comparing with the traditional scheme, this scheme improves the printing speed and alignment precision, and simplifies the system structure, facilitates the assembly and maintenance, greatly saves the cost of production.Firstly, the related technologies background of shaftless gravure press and the principles and characteristics of color register are briefly introduced in this thesis.Secondly, the overall design scheme of color register monitoring system is introduced, and the hardware design scheme of communication gateway is expounded in detail. Thirdly,on the basis of the analysis to the XINTF module and the CAN module in F28335 DSP chip, the underlying network chip drive and CAN drive are developed. Then, the uIP protocol which is chosen for network communication part is transplanted and optimized,and the Modbus frame is embedded in its application layer, so the Modbus/TCP protocol is implemented simply and reliably. Next, after the reference of CANopen protocol standard and the combination with the actual needs, a simple and efficient CANopenprotocol is developed and the real-time scheduling of master station is implemented for the CAN communication part. Finally, the various modules of gateway are integrated to realize the seamless connection between the CAN bus and Ethernet. Aslo, the communication gateway is tested and optimized in the platform of color register monitoring system.The test results shows that the various functions of communication gateway can run normally and meet the needs of reliability and real-time for color register system. It is aslo very well to replace the traditional implementation scheme of IPC.