Application Research Of Devicenet Fieldbus On Servo Drive

Fieldbus technology is an emerging technology in the area of industrial control, which has been wildly used in industrial automation and building automation,and Fieldbus Control System will control the future of Automation Control System. Among the many fieldbus standards, with advantages of open, inexpensive, efficient, and reliable, DeviceNet has been used to control light, buttons, inverter, soft starter motors, and other equipments. Having excellent performances of high accuracy, short response time, servo motors are used in many automation control system as actuator, and to achieve the aim of control from network, more and more servo drives have developed the communication Interface, so it's very important to design DeviceNet network interface for servo drive.DeviceNet is an application layer protocol based on physical layer and data link layer of CAN protocol. This paper introduces part of CAN2.0A protocol, analyses OSI Reference Model of DeviceNet, studies DeviceNet connection technology, the use of the message identifier, I/O data triggered rules, the process of allocation and release the predefined master/slave connection set. Based on in-depth study of DeviceNet protocol, the paper gives a servo drive device profile and object model. According data requirements of servo drive, designs the I/O data formats and data mapping, defines Servo Control Object and Optical Encoder Data Object, gives the definitions of instance attributes, signal flow diagrams and state transition diagrams. At last, presents the hardware and software design of the node, Human-machine interface design and constructs DeviceNet network system using Rockwell Automation's master node and PLC, in this paper.Most of the domestic DeviceNet venders'products are I/O node, which function is simple. Research on servo drive node in this paper is an exploration on develop complex functions DeviceNet nodes, and this is of great significance in DeviceNet nodes development.