ARUCO / VISP Hand-Eye Calibration

Use Cases

This package uses the ARUCO planar target tracker from aruco_ros and the VISP hand-eye calibration from visp_hand2eye_calibration to provide a simple camera pose estimation package. � If you're unfamiliar with Tsai's hand-eye calibration [1], it can be used in two ways:

• eye-in-hand -- To compute the static transform from a robot's end-effector to the optical frame of a camera. In this case, the camera is mounted on the end-effector, and you place the visual target so that it is fixed relative to the base of the rboot.
• eye-on-base -- To compute the static transform from a robot's base to the optical frame of a camera. In this case, the camera is mounted to the base of the robot (or kinematic chain), and you place the visual target so that it is fixed relative to the end-effector of the robot.

Usage

For both use cases, you can either launch the aruco_hand_eye.launch launchfile, or you can include it in another launchfile as shown below. Either way, the launchfile will bring up the aruco_ros tracker and the visp_hand2eye_calibration solver, along with an integration script. By default, the integration script will interactively ask you to accept or discard each sample.

eye-in-hand

<launch>
  <include file="$(find aruco_hand_eye)/launch/aruco_hand_eye.launch">
    <arg name="markerid"   value="582"/>
    <arg name="markersize" value="0.141"/>
    <arg name="publish_tf" value="true"/>

    <arg name="marker_parent_frame" value="/base_link"/>
    <arg name="camera_parent_frame" value="/ee_link"/>

    <arg name="camera" value="/camera/rgb"/>
    <arg name="camera_frame" value="/camera_rgb_optical_frame"/>
  </include>
</launch>

eye-on-base

<launch>
  <include file="$(find aruco_hand_eye)/launch/aruco_hand_eye.launch">
    <arg name="markerid"   value="582"/>
    <arg name="markersize" value="0.141"/>
    <arg name="publish_tf" value="true"/>

    <arg name="marker_parent_frame" value="/ee_link"/>
    <arg name="camera_parent_frame" value="/base_link"/>

    <arg name="camera" value="/camera/rgb"/>
    <arg name="camera_frame" value="/camera_rgb_optical_frame"/>
  </include>
</launch>

Examples

For calibrating a kinect mounted to the base of a manipulator that can grasp the target:

roslaunch aruco_hand_eye kinect.launch ee_frame:=/my/robot/ee_link

References

[1] Tsai, Roger Y., and Reimar K. Lenz. "A new technique for fully autonomous and efficient 3D robotics hand/eye calibration." Robotics and Automation, IEEE Transactions on 5.3 (1989): 345-358.