Servo motor communication via CAN serial port
Optional to any SmartMotor, Animatic’s patent-pending Combitronic communication uses a CAN serial port to join up to 120 SmartMotor servos so that any SmartMotor may read, write, or control any other SmartMotor. The code to accomplish this task is to tag a local variable or command with a colon and the SmartMotor’s CAN address.
All machine designs start with the decision between centralized control and distributed control. Having one centralized master in the entire machine’s communication usually leaves the designer with an often overwhelmingly complex cabinet of controls, rails, mounts, cabling and wires looking similar to a science fiction nightmare, as well as an overworked master. As more engineers move towards distributed control with multiple machine parts controlling separate aspects of the whole machine, issues arise here as well. The problem now becomes communication, where the interaction and coordination needed from each node to achieve tasks by the machine as a whole fall by the wayside. It’s between the headaches of centralized and distributed control that Combitronic communication provides the solution: an invisible communication protocol that works between SmartMotor servos for data-sharing and coordination while not interfering with DeviceNet or CANopen communication coming from the PLC/HMI/master. With Combitronic and SmartMotor, there is no need for a PLC, Animatics noted.
With Combitronic, no new fieldbus network has to be learned, so the user doesn’t have to write a stitch of code for motor to motor specific communication. Simply by addressing the SmartMotor servos in the program, a group of SmartMotor products becomes one multi-tasking, data-sharing, multi-axes machine with access to all motion, program, I/O and data functions of every other SmartMotor. A group of only 10 SmartMotor integrated servos on a Combitronic network would have 20 communication ports and between 70 and 170 points of I/O communications.
Feedback: At the Animatics Institute in October 2010, programmers reportedly appreciate that each of their SmartMotor demos had already been addressed over CAN and with the proper code could control any other engineer’s SmartMotor movement with a few swipes at the keyboard.
– Edited by Gust Gianos, CFE Media, Control Engineering, www.controleng.com