Codesys — Ros2 !!top!!

| Method | Mean latency (μs) | Max jitter (μs) | CPU load (one core) | |--------|------------------|----------------|---------------------| | Native DDS (C++) | 85 | 210 | 12% | | CODESYS→ROS2 (lock-free) | 220 | 380 | 18% | | CODESYS→OPC UA→ROS2 | 3850 | 1200 | 25% |

Map IEC 61131 types (e.g., REAL , BOOL ) correctly to ROS2 message types (e.g., float32 , bool ) to avoid serialization errors.

Traditional industrial robot arms programmed in CODESYS can handle fast, repeatable pick-and-place trajectories. By integrating ROS2, engineers can attach a 3D camera to the system, use ROS2 OpenCV or point-cloud processing nodes to identify randomly oriented items, and send the exact coordinates down to the CODESYS PLC for execution. 3. Digital Twins and Simulation

Executing highly repetitive, microsecond-level control loops. ROS 2: The Robotic Brain codesys ros2

It's helpful to visualize how these pieces typically fit together. The diagram below illustrates a high-performance integration pattern where CODESYS handles low-level hardware control on an edge computer, while ROS 2 runs on a separate computer for high-level processing.

// Control Flags bConnect : BOOL := TRUE; bConnected : BOOL; xPublishTrigger : BOOL;

: PLCs excel at real-time, deterministic control. They manage microsecond-level I/O loops, execute safety functions, and communicate via robust industrial protocols like EtherCAT, PROFINET, and EtherNet/IP. However, they lack the computational flexibility needed for complex tasks like autonomous navigation, dynamic path planning, or machine learning. | Method | Mean latency (μs) | Max

: Sub-millisecond communication; the PLC acts as a native ROS2 node.

This paper presented a practical, real-time capable bridge between CODESYS PLCs and ROS2. By embedding a ROS2 client library into the CODESYS runtime and using a lock-free FIFO between the real-time task and a lower-priority spin thread, we achieve mean latencies of 220μs—suitable for high-speed robotic control. The architecture preserves the determinism of IEC 61131-3 code while leveraging the full ROS2 ecosystem. Source code for the CODESYS ROS2 client library is available under Apache 2.0 license (anonymized for review).

– The authors thank the CODESYS community and ROS-Industrial consortium for feedback. dynamic path planning

Let’s look at a practical workflow for connecting a CODESYS-controlled robotic arm or AMR base to a ROS 2 navigation stack using an OPC UA bridge. Step 1: Configure the CODESYS OPC UA Server Open your CODESYS project. Add a object to your application tree.

Deploy a real-time capable operating system. Ubuntu LTS configured with the PREEMPT_RT patch is the industry standard. Install the ROS2 distribution (such as Jazzy Jalisco or Humble Hawksbill) alongside the CODESYS Control for Linux SL runtime. Step 2: Define the Interface Contract Determine exactly what data needs to cross the boundary.

OPC UA is the standard for secure, vendor-neutral industrial communication and is natively built into most CODESYS runtimes.

: PLCs like CODESYS are designed for 24/7 industrial reliability and handle low-level hardware communication (e.g., motor drives, sensors) more robustly than standard ROS 2 drivers. High-Level Intelligence