Accessing ARI sensors

Section

ARI hardware - reference

In this tutorials we’ll learn how to access to the different sensors in ARI.

Accessing the cameras

Most of the sensor readings of ARI can be visualized in rviz. Though you can also use image_view or rqt_gui. Let’s have a look at both procedures.

1. rviz visualization

In order to start the rviz GUI with a predefined configuration you need the ari_bringup package, which is accessible from the PAL docker image (see Developing with docker and ROS).

To install ari_bringup, execute

apt install pal-gallium-ari-bringup-dev

Then start rviz:

export ROS_MASTER_URI=http://ari-0c:11311
rosrun rviz rviz -d `rospack find ari_bringup\`/config/ari.rviz

The image below shows how the torso front and back cameras are visualized in rviz.

2. image_view visualization

Run image_view tool to visualize the desired camera as follows:

export ROS_MASTER_URI=http://ari-0c:11311
rosrun image_view image_view image:=/torso_back_camera/fisheye2/image_raw _image_transport:=compressed

When visualizing images from an external computer through WiFi, it is recommended to use the compressed topic to reduce bandwidth and latency.

3. rqt_gui visualisation

You can also use rqt_gui, a tool that allows incorporate multiple plugins and thus, have a better understanding of the system. One such example is rqt_human_radar (see 🚧 Tutorial: Tooling and debugging of human-robot interactions), a plugin for rqt_gui, where additional visualization tools for ROS4HRI can be combined.

To use rqt_gui, follow the next steps:

1. Run rqt_gui:

   export ROS_MASTER_URI=http://ari-0c:11311
   rosrun rqt_gui rqt_gui
   

2. In the top menu, select: Plugins ‣ Visualization ‣ Image View

3. Select the topic of the camera you want to visualize. In the image below we are visualizing the /torso_back_camera/fisheye1/image_raw/*.

Accessing the microphones

Please refer to ARI microphone array and audio recording to learn how to access the audio data.