| With the further development of China’s industrialization and the riseof labor costs, the demand of automation equipment which can completethe complex operation efficiently and accurately is rising, thereforedistributed control systems such as automation line, industrial robots andso on are developing rapidly. Traditional servo drivers which receiveposition commands by means of buttons, LED digital tube, digital pulsecannot meet requirements, the network interface of the servo driver arisesat the historic moment. Currently the research and develop of servo driverwith network interface is lagging behind, which become a bottleneck thatlimits the development and promotion of high-end automation equipment.Due to the low cost and good performance, CAN interface hasgradually become the standard interface technology of foreign low-endservo driver, CANopen which is the application layer protocol of theCAN bus, stipulates the rules of CAN communication, and formulates agroup of sub-protocol related to equipment and devices for specificapplications, which increase the efficiency of development and devicecompatibility.This paper firstly summarizes the history and current situation of thedevelopment and research of servo system, and the development trend ofthe AC servo system is discussed; Then several popular bus networktechnologies are compared, and the advantages of CAN bus in servodriver are analyzed. The CANopen protocol and its drive and motioncontrol sub-protocol DS402are analyzed, how servo driver uses CANbus in communication is researched. Finally the overall structure anddesign of software and hardware of servo driver are expounded, a methodwhich increases a CANopen slave station to the original driver isproposed, a software to implement the CANopen protocol is used, and thehardware and software implementation process of CANopen interface aregiven.Finally, an AC servo system experiment platform is set up, the servodriver with a CAN interface executes the command perfectly and returnsstatus information. The experimental results show that the hardware andsoftware design of CANopen interface is feasible. |
