We have been studying intelligent motion control system for next industrial revolution. Standard conformance and integrated development are key features of modern automation systems which demand seamless integration of high-speed communication with conventional control logics. There is a compelling need for a self-contained, scalable, IDE to support industrial communication protocols.
We choose an open source IDE for IEC 61131-3 PLC application, called Beremiz, and integrated it with IgH EtherCAT master stack to support EtherCAT communication in an IDE. Since the whole procedures from the project setup to runtime monitoring are highly automated, our IDE provides effective ways to develop the PLC application with EtherCAT communication profile.
Our extension provides PLC program code generation based on EtherCAT Slave Information (ESI) XML file, and various EtherCAT device management features such as EEPROM download/upload, SDO/PDO management, network monitoring and so on. EtherCAT management functions are implemented with EtherCAT commandline tool. Our extension also can support almost EtherCAT devices which conforms the EtherCAT standard.
Another important component of motion control system is a motion controller. It should support real-time guaranteeing for control message transfer and rich development APIs, low cost….. Our lab have been developed Xenomai based motion controller based on Beaglebone black board with 4dsystem LCD 7″. We have tested a simple continuous position control (CSP) motion application with HMI. We have tested from 2 ms to 500 us with multiple motor drives (up to 16 drive). Since Beaglebone black has the less computing power, frame transmission interval is worse than Industrial PC based controller even running with a single motor drive.
To overcome this performance degradation, we propose a laze transmission heuristic. The result is awesome! We can achieve the 300 us minimum safe (jitter less than 1 % of control cycle) cycle time with single motor drive.
Using the PYRO (Python Remote Object) interface, IDE can be easily communicate with motion controller. After the application build phase, newly created PLC executable will be transferred by PYRO interface. In execution phase, PLC executable is remotely started, stopped, and monitored. (provided by IgH EtherCAT Master stack).