How to use a rviz2 visualization

Prerequisite

Having completed tutorial 2.

Overview

This tutorial shows how to set up an RViz2 visualization for HPP using the RVizVisualizer from pyhpp_rviz. Unlike the web-based viewer used in tutorials 2–5, this visualizer communicates over ROS 2 topics and displays the robot, paths, and landmarks directly inside RViz2.

Setting up the simulation

The base tutorial docker image does not include ROS 2 control packages. Build the extended image from the tutorial 6 directory on the host machine (not inside the container):

cd tutorial_6
docker build --build-arg DOCKER_USER=`id -u` --build-arg DOCKER_GROUP=`id -g` \
    -t hpp-ros2:tuto .

Then start the container from the root shared directory:

cd ../../..
./src/hpp_tutorial/tutorial_6/run_docker.sh

Compiling the HPP RViz2 plugins

On your first make all from tutorial 1, the RViz2 plugin sources were notcompiled. Build hpp-rviz:

cd src
make hpp-rviz.install

export the package path

export ROS_PACKAGE_PATH=/home/user/devel/src/:/opt/openrobots/share/:$ROS_PACKAGE_PATH

Initializing the viewer

In the docker container, cd into tutorial_6 directory and run:

python -i init.py

The script is identical to tutorial 2 up to the computation of path p The only difference is that it uses RVizVisualizer instead of viser Viewer.

from pyhpp_rviz import RVizVisualizer as Viewer

v = Viewer()
v.initViewer(robot=robot)

Configuring RViz2

Open a second terminal in the container:

docker exec -it hpp bash
rviz2

In RViz2, set the Fixed Frame to world (in the Global Options panel).

Set the Frame Rate to 300

For each model loaded with urdf.loadModel, add a RobotModel display and set its Description Topic to the topic published for that model (e.g. /panda/robot_description, /ground/robot_description, /box/robot_description). The prefix matches the name passed to urdf.loadModel.

Add a TF display to visualize all frame transforms published by the viewer.

Disable TF arrows and put Frame Time Out to 1e+07

There is a rviz config file on hpp_tutorial/launch/tuto6.rviz

rviz2 -d hpp_tutorial/launch/config.rviz

Call v(q_init) in the Python terminal to place all objects in their initial configuration. The scene should now appear in RViz2.

Visualizing a configuration

v(q_init)

Use v(config) to display a configuration on rviz2 like is done with viser.

Visualizing a path

Add the Trajectory plugin (from the HPP RViz2 plugins) to RViz2. A control panel will appear at the bottom of the screen.

Load a path from the Python terminal:

v.loadPath(path)

The panel lets you slide through the path parameter to inspect any intermediate configuration.

To display the spatial trace of a frame along the path, use:

v.displayPath(path, target_frame="panda/gripper")

You can also trigger this from RViz2 by entering the frame name directly in the DisplayTrajectory panel.

Adding landmarks

Add the Landmark tool from the RViz2 toolbar (installed with the HPP RViz2 plugins). Add the Landmark display to visualize the landmarks in the scene.

Landmarks can be placed in three ways:

• Interactively: select the Landmark tool in the toolbar, then click in the 3D view. Drag the landmark with the interact tool for moving it or Right-click a landmark marker and choose Edit position to adjust it numerically with the interact tool too

• From a named frame (Python):

  v.addLandmarkFromFrame("panda/gripper", "first landmark")
  

  This publishes the current pose of the given frame as a landmark.

• From explicit coordinates (Python):

  v.addLandmark(xyz=[0.8, 0.0, 1.0], quat_xyzw=[0.0, 0.0, 0.0, 1.0], "landmark")
  

Summary of viewer methods