cu-ros2-bridge 1.0.0

Copper bridge for ROS 2 messaging over Zenoh transport.
Documentation

cu-ros2-bridge

Bidirectional Copper bridge for ROS 2 messaging over Zenoh transport.

Config

Bridge-level config:

  • domain_id: ROS 2 domain id (default 0).
  • namespace: ROS 2 namespace (default copper).
  • node: ROS 2 node name (default node).
  • zenoh_config_file: path to a Zenoh JSON5 config file (optional).
  • zenoh_config_json: inline Zenoh JSON5 config (optional).

Per-channel config (bridges[].channels):

  • route: ROS 2 topic path used by that channel.

Rx-only options:

  • queue_mode: "fifo" (default) First In First Out mode. Delivers samples in order, one per cycle. "ring" creates a buffer and drops oldest sample when full.
  • ring_size: depth of the ring buffer when queue_mode is "ring" (default 1).

Example:

bridges: [
  (
    id: "ros2",
    type: "bridges::DemoRos2Bridge",
    config: {
      "domain_id": 0,
      "namespace": "copper",
      "node": "bridge_node",
    },
    channels: [
      Tx(id: "outgoing", route: "/output"),
      // fifo: ordered delivery, one sample per cycle (default)
      Rx(id: "incoming", route: "/input"),
      // ring: always receive the freshest sample
      Rx(id: "sensor",   route: "/sensor", config: {"queue_mode": "ring"}),
    ],
  ),
],

Payload codec registry

The bridge uses a payload codec registry keyed by Copper payload type. It ships with:

  • bool, i8, i16, i32, i64, u8, u16, u32, u64, f32, f64, String

To add your own payloads, implement cu_ros2_payloads::RosBridgeAdapter for the payload type and register it once at startup:

cu_ros2_bridge::register_ros2_payload::<MyPayload>();

Wire encoding

Copper -> ROS 2 samples are serialized as OMG CDR little-endian (CdrLe). Inbound samples use cdr::deserialize, which reads the CDR encapsulation header and accepts either endianness.

ROS 2 interop test

The ros2_interop test auto-detects a sourced ROS 2 environment. If ros2, std_msgs, or rmw_zenoh_cpp are unavailable, the test prints a warning with the skip reason and returns success. The Linux CI image includes ROS 2 Lyrical and rmw_zenoh_cpp, so the same normal test flow exercises real ROS 2 bridge interoperability in CI.

When available, the test starts rmw_zenohd, runs a real ROS 2 subscriber with ros2 topic echo --once, publishes an std_msgs/msg/Int32 through Ros2Bridge, and requires the ROS 2 process to print data: 42.

cargo test -p cu-ros2-bridge --test ros2_interop -- --nocapture