Why use a CAN-bus network and CANopen communication protocol for decentralized axes control?

Some of the most important reasons are transmission security, speed and reliability largely due to the uniqueness of the data transmission of the CAN network. In a CAN network there is no addressing of subscribers or stations in the conventional sense, but instead, prioritized messages are transmitted. A transmitter sends a message to all CAN nodes (broadcasting). Each node decides on the basis of the identifier received whether it should process the message or not. The identifier also determines the priority that the message enjoys in competition for bus access.

Another key reason is international standardization. Open fieldbus systems enable the construction of machines by connecting components from multiple vendors, while minimizing the effort required for interfacing. To achieve an open networking system, it is necessary to standardize the various layers of communication used.

A widely accepted standard for these layers of communication is provided with CANopen. CANopen is a standardized communication profile for simple networking of CANopen-compatible devices from many different manufacturers. The profile family, which is available and maintained by CAN in Automation (CiA), consists of the application layer and communication profile (DS301), various frameworks and recommendations (CiA DS-30x) and various device profiles (CiA DS-40x). The CANopen standard defines various device profiles to enable connection of different types of devices, including for example: electric servovalves, pumps, drives, controllers, position transducers, etc.

For more information, visit http://www.canopen.org/