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[isaacsim.ros2.tf_viewer] TF Viewer#

Version: 2.3.2

Overview#

The TF Viewer extension provides real-time visualization of ROS 2 transform (TF) data directly within the Isaac Sim viewport. It displays the coordinate frame hierarchy broadcast through the ROS 2 tf2 system, showing relationships between frames, their spatial positions, and orientations as they update dynamically.

Functionality#

The extension connects to a ROS 2 system to monitor transform broadcasts and renders them as visual elements in the viewport. Users can observe how coordinate frames relate to each other through parent-child relationships, track frame positions and orientations in 3D space, and understand the complete transform tree structure emanating from a chosen root frame.

Transform Listening#

The extension uses a dedicated transform listener that operates independently from the main application thread. For ROS 2, it initializes a node with a transform buffer and listener that subscribes to /tf and /tf_static topics. The listener continuously processes incoming transform messages and maintains an up-to-date view of all available frames and their relationships.

Transform queries retrieve both individual frame-to-frame transformations and complete transform trees relative to a specified root frame. The system returns frame names, their transforms as translation and rotation tuples, and the parent-child relationships that define the frame hierarchy.

Visual Representation#

The viewport manipulator renders multiple visual components to represent the transform data:

  • Frame markers: Visual indicators at each frame’s origin

  • Frame names: Text labels identifying each coordinate frame

  • Coordinate axes: RGB-colored axes showing frame orientation (X-red, Y-green, Z-blue)

  • Relationship arrows: Lines connecting parent and child frames

Each visual element can be independently configured for visibility, color, size, and other display properties. The visualization updates automatically when new transform data arrives or when configuration settings change.

Configuration Options#

Users can customize the visualization through several parameters:

  • Root frame selection: Choose which frame serves as the reference for the transform tree

  • Component visibility: Toggle display of frames, names, axes, and arrows independently

  • Visual styling: Adjust colors (RGBA), sizes, lengths, and thickness values for each component

  • Implementation mode: Switch between C++ and Python transform listener implementations via settings

The exts."isaacsim.ros2.tf_viewer".cpp setting controls whether to use the C++ implementation for transform listening. When set to true, it provides better performance for processing high-frequency transform updates. Setting exts."isaacsim.ros2.tf_viewer".include_root_frame to true ensures the root frame appears in the visualization even when it’s not explicitly published in the transform tree.

UI Components#

TF Viewer Window#

The window presents controls organized into collapsible sections for managing different aspects of the visualization. An update frequency indicator shows the rate at which transform data refreshes. Controls for the root frame allow users to specify which coordinate frame serves as the reference point for displaying the entire transform tree.

Separate sections provide toggles and sliders for each visual component type. Frame marker controls adjust visibility, color channels, and size. Name label controls manage text display properties. Axis controls configure the length and thickness of coordinate axes. Arrow controls modify the appearance of lines connecting related frames.

A reset button clears the transform buffer to remove stale data and resolve timing-related warnings. The window integrates with the application’s menu system, appearing under a configurable menu path for easy access.

Integration#

The extension depends on isaacsim.ros2.bridge to establish ROS 2 connectivity and handle the underlying communication with the ROS 2 system. It uses **omni.ui.scene** to create the viewport manipulator that renders transform visualizations as scene overlays. The **omni.kit.viewport.utility** dependency provides viewport context and window management capabilities needed to properly attach the visualization to the active viewport.

Enable Extension#

The extension can be enabled (if not already) in one of the following ways:

Define the next entry as an application argument from a terminal.

APP_SCRIPT.(sh|bat) --enable isaacsim.ros2.tf_viewer

Define the next entry under [dependencies] in an experience (.kit) file or an extension configuration (extension.toml) file.

[dependencies]
"isaacsim.ros2.tf_viewer" = {}

Open the Window > Extensions menu in a running application instance and search for isaacsim.ros2.tf_viewer. Then, toggle the enable control button if it is not already active.

Extension: {{ extension_version }}

Documentation Generated: Jun 05, 2026

Settings#

exts.”isaacsim.ros2.tf_viewer”.cpp#

  • Default Value: true

  • Description: Whether to use the C++ implementation to listen to the tf and process the incoming data; if false, the Python implementation will be used (may degrade performance considerably).

exts.”isaacsim.ros2.tf_viewer”.include_root_frame#

  • Default Value: true

  • Description: Whether to include the pose of the root frame when drawing the TF in the viewport if not listed; root frame’s pose is defined with position (0,0,0) and orientation (0,0,0,1) as xyzw quaternion.

Python API#

ROS 2 Transform Listener module for Isaac Sim.

This module provides an interface to ROS 2 transform (tf) functionality, allowing Isaac Sim to listen to and process transform messages from ROS 2. It enables visualization and utilization of coordinate frames broadcast through the ROS 2 tf2 system.

The module allows applications to: - Connect to a ROS 2 system - Subscribe to transform messages - Process and retrieve transformation data - Visualize transform hierarchies within Isaac Sim

class ITransformListener
finalize(
self: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
) → None

Finalize and clean up the transform listener.

Unsubscribes from tf topics and cleans up ROS 2 resources.

get_transforms(
self: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
root_frame: str,
) → Tuple[List[str], Dict[str, Tuple[Tuple[float, float, float], Tuple[float, float, float, float]]], List[Tuple[str, str]]]

Get all transforms relative to the specified root frame.

This method computes transforms for all frames relative to the specified root frame and returns the frame data, transform data, and frame relationships.

Parameters:

root_frame (str) – The reference frame ID to compute transforms against.

Returns:

A tuple containing three elements:

  • list of str: Available frame IDs

  • dict: Map of frame IDs to transforms (translation: xyz, rotation: xyzw)

  • list of tuple: Parent-child relationships between frames

Return type:

tuple

initialize(
self: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
ros_distro: str,
) → bool

Initialize the transform listener with the specified ROS 2 distribution.

Parameters:

ros_distro (str) – The ROS 2 distribution name to use (e.g., “humble”, “foxy”).

Returns:

True if initialization was successful, False otherwise.

Return type:

bool

reset(
self: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
) → None

Reset the transform buffer.

Clears all stored transform data.

spin(
self: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
) → bool

Process incoming transform messages.

This method should be called regularly to process new transform data from ROS 2.

Returns:

True if transforms were processed successfully, False otherwise.

Return type:

bool

acquire_transform_listener_interface(
plugin_name: str = None,
library_path: str = None,
) → isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener
release_transform_listener_interface(
arg0: isaacsim.ros2.tf_viewer.bindings._transform_listener.ITransformListener,
) → None