CANopen higher layer protocol for motion control

May 8, 2006
This paper provides an overview of the CANopen specification (DS-301, DSP-302) and explores in more detail the device profiles for generic I/O modules (DS-401), drives and motion control (DSP-402), and IEC 61131-3 programmable devices (DS-405).
By Wilfred Voss, President, esd electronics

THE ULTIMATE goal of CANopen is to provide OEMs and end users a certain level of manufacturer independence by providing standard device profiles for a continuously increasing number of controls. CANopen is an industrial networking technology based on the serial bus system Controller Area Network (CAN), which connects a master device with numerous slave devices such as digital I/O, analog I/O, motion controllers, encoders, sensors, and actuators.

Developed originally for passenger cars, the CAN two-wire bus system is already in use in millions of industrial devices all over the world. In contrast to other field-bus technologies, CAN/CANopen was specifically designed for real-time control and maximum reliability, which made it very suitable for time critical tasks, for instance, motion control.

Standardized device profiles are very effective supplements to a higher layer protocol such as CANopen. The standardization effort by CAN-in-Automation is one initiative to come closer the ultimate goal of providing OEMs and end users a high level of manufacturer independence when it comes to the implementation of off-the-shelf electronic devices into their design. Ultimately, CANopen helps to drastically simplify system integration.