URDF Loading

Rewire automatically detects topics ending in /robot_description and loads the URDF for 3D visualization in the Rerun viewer.

How it works

When Rewire receives a message on a /robot_description topic (typically std_msgs/String):

1. Parses the URDF XML to extract the robot name
2. Loads the robot model geometry using Rerun's UrdfDataLoader
3. Logs the model as an Asset3D archetype
4. Logs the raw URDF text as a TextDocument for inspection

The robot model appears in the 3D viewport with all links and joints.

Mesh resolution

URDF files often reference meshes with package:// URLs. For these to resolve, Rewire needs the ROS 2 package paths:

export AMENT_PREFIX_PATH=/opt/ros/humble/share
rewire record

If AMENT_PREFIX_PATH is not set, Rewire will log a warning and skip mesh loading. The robot skeleton (links and joints) will still be visible.

Mesh resolution also applies to visualization_msgs/Marker messages that use the MESH_RESOURCE type. Supported mesh formats: GLB, glTF, OBJ, STL, and DAE/COLLADA. URI schemes package://, file://, and absolute paths are all supported.

Multi-robot support

Rewire derives a TF frame prefix from the topic namespace of each /robot_description topic. This lets multiple robots coexist in the same viewer without frame name collisions:

The prefix uses a leading / to match the ROS TF convention. Each robot appears as a separate entity tree in the Rerun viewer, with its own set of TF frames.

Custom message types

If your robot description is published on a non-standard topic or message type, you need to source your ROS 2 workspace so Rewire can deserialize the message:

source /opt/ros/humble/setup.bash
source ~/my_ws/install/setup.bash
rewire record

Workspace sourcing is also needed for custom type resolution on pre-Jazzy distributions.