isaac-sim-ros2-bridge

name

isaac-sim-ros2-bridge

description

Setting up and using the ROS 2 Bridge in Isaac Sim 6.0 (Kit 110) for publishing and subscribing to ROS 2 topics from simulation. Covers bridge architecture, OmniGraph node setup for sensors/commands, Nav2 integration, and multi-robot namespacing. Use when: connecting Isaac Sim to ROS 2, publishing sensor data (camera, LiDAR, odometry) from simulation to ROS 2, subscribing to robot commands from Nav2 or other ROS 2 nodes, or setting up multi-robot namespaced ROS 2 communication in simulation. Triggers on: ROS 2 bridge, OmniGraph ROS2, Nav2 Isaac Sim, isaacsim.ros2.bridge, ROS2PublishLaserScan, cmd_vel subscribe, multi-robot namespace ROS2.

Isaac Sim ROS 2 Bridge

Architecture

The ROS 2 Bridge in Isaac Sim 6.0 is extension-based (isaacsim.ros2.bridge) and built on OmniGraph action graphs. Publishers, subscribers, and services are only active when play is pressed.

Extension Stack

Extension	Purpose
isaacsim.ros2.core	Backend libraries, settings, lightweight ROS 2 libs
isaacsim.ros2.nodes	OmniGraph nodes for topics/services
isaacsim.ros2.bridge	Top-level bridge extension (enables all)
isaacsim.ros2.tf_viewer	TF tree visualization
isaacsim.ros2.urdf	URDF import with ROS 2 conventions
isaacsim.ros2.examples	Sample scenes (Nova Carter, iw_hub, hospital, office)
isaacsim.ros2.sim_control	Simulation control via ROS 2 services

Prerequisites

No manual setup is required for the default workflow. When isaacsim.ros2.core starts, it reads ROS_DISTRO; if unset, it falls back to the lightweight ROS 2 libs bundled inside the extension and sets internal_lib_fallback=True. The isaac-sim.sh / python.sh launchers auto-source setup_ros_env.sh, which exports ROS_DISTRO, RMW_IMPLEMENTATION, and LD_LIBRARY_PATH for the bundled libs before the process starts.

Source a system ROS 2 install (/opt/ros/<distro>/setup.bash) in the parent shell only when you need message types or RMW implementations not provided by the bundled libs. On Linux, LD_LIBRARY_PATH must be set in the parent shell (the dynamic linker reads it at process start), which is why this step is shell-sourced and not handled by the extension at runtime.

Pass --no-ros-env to bypass the auto-sourcing; in that case the parent shell must provide a working ROS 2 environment.

[Code: scripts/prerequisites.sh]

OmniGraph ROS 2 Nodes

All ROS 2 communication is configured through OmniGraph action graphs. Key node types:

Publishers

Node Type	Topic Type	Use Case
ROS2PublishClock	rosgraph_msgs/Clock	Sim time sync
ROS2PublishJointState	sensor_msgs/JointState	Joint positions/velocities
ROS2PublishOdometry	nav_msgs/Odometry	Robot odometry
ROS2PublishLaserScan	sensor_msgs/LaserScan	Lidar data
ROS2PublishImage	sensor_msgs/Image	Camera RGB/depth
ROS2PublishCameraInfo	sensor_msgs/CameraInfo	Camera intrinsics
ROS2PublishTransformTree	tf2_msgs/TFMessage	TF frames
ROS2PublishSemanticLabels	std_msgs/String	Semantic segmentation labels
ROS2PublishPointCloud	sensor_msgs/PointCloud2	Lidar/depth point clouds
ROS2PublishImu	sensor_msgs/Imu	IMU data

Subscribers

Node Type	Topic Type	Use Case
ROS2SubscribeJointState	sensor_msgs/JointState	Joint commands
ROS2SubscribeTwist	geometry_msgs/Twist	Velocity commands (cmd_vel)
ROS2SubscribeAckermannDrive	ackermann_msgs/AckermannDriveStamped	Ackermann steering commands

Generic / extra

Node Type	Use case
ROS2Publisher / ROS2Subscriber	generic publish/subscribe for arbitrary message types
ROS2PublishBoundingBox2D / ROS2PublishBoundingBox3D	annotator output to ROS 2
ROS2PublishRgbd	combined RGB+D publishing
ROS2PublishSemanticSegmentation / ROS2PublishInstanceSegmentation	segmentation outputs

Setting Up a ROS 2 Bridge Graph (Python)

The repo ships a canonical reference for building a ROS 2 publishing action graph with og.Controller.edit(...), including connecting OnPlaybackTick to publisher nodes, wiring IsaacReadSimulationTime into a ROS2PublishClock, and creating a matching rclpy subscriber inside the same script.

• Reference example: source/standalone_examples/api/isaacsim.ros2.bridge/clock.py

When extending this pattern, use the current isaacsim.ros2.bridge.ROS2Publish* / ROS2Subscribe* node names (the legacy omni.isaac.ros2_bridge.* namespace is deprecated and will not load on Kit 110).

Migration: see Migrating ROS 2 OmniGraph nodes for the node-by-node rename map, and Renaming Extensions for the broader omni.isaac.* → isaacsim.* mapping.

Multi-Robot Namespacing

For multi-robot scenes, each robot needs its own namespace for ROS 2 topics. The repo's multi-robot scenario (Carter on hospital/office) demonstrates the manual loading + per-robot setup pattern; scripts/multi_robot_namespacing.py in this skill provides the per-robot graph factory with namespaced odom / TF / cmd_vel.

• Scenario reference: source/standalone_examples/api/isaacsim.ros2.bridge/carter_multiple_robot_navigation.py
• Per-robot graph factory: scripts/multi_robot_namespacing.py

Nav2 Integration

To use Nav2 with Isaac Sim ROS 2 Bridge:

1. Publish required topics: /odom, /tf, /scan (or /pointcloud), /joint_states
2. Subscribe to: /cmd_vel
3. Publish sim clock on /clock and set use_sim_time: true in Nav2 params

Known Issues (Isaac Sim 6.0 rc.22)

• ROS 2 bridge only activates on timeline.play() — topics are not published in stopped state
• Camera publishers require camera prims to have render products attached
• TF tree can become inconsistent if robot prim paths change at runtime
• Bundled ROS 2 libs may lack message types needed for custom topics — source a system ROS 2 install in the parent shell before launching Isaac Sim

Sample Scenes

Pre-built example USD files (from isaacsim.ros2.examples):

Scene	Path	Description
Nova Carter Navigation	/Isaac/Samples/ROS2/Scenario/carter_warehouse_navigation.usd	Single robot Nav2
Nova Carter Joint States	/Isaac/Samples/ROS2/Scenario/carter_warehouse_navigation_joint_states.usd	With joint state publishing
iw_hub Navigation	/Isaac/Samples/ROS2/Scenario/iw_hub_warehouse_navigation.usd	iw_hub AMR
Multi-Robot Navigation	ROS2/Navigation/Multiple Robots category	Fleet Nav2
Hospital Scene	/Isaac/Samples/ROS2/Scenario/hospital_scene.usd	Perceptor + hospital
Office Scene	/Isaac/Samples/ROS2/Scenario/office_scene.usd	Office navigation