External real-time position and orientation control loop for increasing the path accuracy of industrial robots
EtherCAT® Bridge ECX-EC connects PC and robot controller
At the CFRP NORD Research Center, the Fraunhofer Institute for Manufacturing Technology and Advanced Materials (IFAM) is working on solutions to increase the accuracy of industrial robots so that they can be used in the future for machining large structures in aircraft construction.
Industrial robots with six axes offer advantages in this area of application compared to the large machine tools in gantry design used to date, because the machine tools are relatively expensive, heavy and in some cases inflexible. Although industrial robots equipped with a high-frequency milling spindle are suitable in principle for CFRP machining, they have not yet achieved the path accuracies required in aircraft construction.
Connecting two EtherCAT segments
The ECX-EC module connects two EtherCAT segments with each other. The EtherCAT bridges contain two EtherCAT slave interfaces. They are used to integrate the EtherCAT networks so that process data can be exchanged between two EtherCAT segments.
For synchronization (DC) of the EtherCAT masters the ECX-EC module uses the exact time difference between both slave timestamps as CoE object. This enables a master to adapt to the other master in terms of time. For time synchronization in the redundancy case, the ECX-EC bridge is used simultaneously as the first and last slave. This enables the master to keep the slaves in both networks synchronized.
The bridge has an Ethernet interface according to IEEE 802.3 and supports Ethernet over EtherCAT (EoE) "switch port". The firmware can be updated via FoE.
The ECX-EC module can be configured with common EtherCAT configuration tools (e.g. esd EtherCAT Workbench, Twin-CAT® and others). It is designed as a compact DIN rail module for DIN-EN mounting rail installation (TS 35).
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External control loop for increasing the path accuracy of industrial robots External control loop for increasing the path accuracy of industrial robots 1 MB