aruco_ros

Software package and ROS wrappers of the Aruco Augmented Reality marker detector library.

Features

• High-framerate tracking of AR markers

• Generate AR markers with given size and optimized for minimal perceptive ambiguity (when there are more markers to track)

• Enhanced precision tracking by using boards of markers

• ROS wrappers

Applications

• Object pose estimation
• Visual servoing: track object and hand at the same time

ROS API

Messages

• aruco_ros/Marker.msg

   Header header
   uint32 id
   geometry_msgs/PoseWithCovariance pose
   float64 confidence
  

• aruco_ros/MarkerArray.msg

   Header header
   aruco_ros/Marker[] markers
  

Kinetic changes

• Updated the Aruco library to version 3.0.4

• Changed the coordinate system to match the library’s, the convention is shown in the image below, following rviz conventions, X is red, Y is green and Z is blue.

Test it with REEM

• Open a REEM in simulation with a marker floating in front of the robot. This will start the stereo cameras of the robot too. Since this is only a vision test, there is nothing else in this world apart from the robot and a marker floating in front of it. An extra light source had to be added to compensate for the default darkness.

    roslaunch reem_gazebo reem_gazebo.launch world:=floating_marker
    

• Launch the image_proc node to get undistorted images from the cameras of the robot.

    ROS_NAMESPACE=/stereo/right rosrun image_proc image_proc image_raw:=image
    

• Start the single node which will start tracking the specified marker and will publish its pose in the camera frame

    roslaunch aruco_ros single.launch markerId:=26 markerSize:=0.08 eye:="right"
    

the frame in which the pose is refered to can be chosen with the 'ref_frame' argument. The next example forces the marker pose to
be published with respect to the robot base_link frame:

    roslaunch aruco_ros single.launch markerId:=26 markerSize:=0.08 eye:="right" ref_frame:=/base_link
    

• Visualize the result

    rosrun image_view image_view image:=/aruco_single/result