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Only released in EOL distros:   indigo kinetic

Documentation

Refer to the Tutorial for instructions on how to calibrate a Kinect to the turtlebot_arm. The tutorial is for the fuerte version of this package, so be careful and flexible when following it!. Trust this page (already updated for indigo) in case of contradiction.

Video

Files

calibrate.launch

• Starts all the necessary nodes to calibrate an external kinect. To calibrate an on-board camera, you will probably need to comment the openni.launch include.

Nodes

calibrate_kinect_checkerboard

Detects a checkerboard in an image, and then waits for the user to move the arm to specified points on the checkerboard to determine the transform between the kinect and the robot

Subscribed Topics

/camera/rgb/image_mono (sensor_msgs/image)

• Monochromatic image topic for the Kinect (this is used for detecting the checkerboard)

/camera/rgb/camera_info (sensor_msgs/CameraInfo)

• Camera info from Kinect.

Published Topics

~calibration_pattern_out (sensor_msgs/Image)

• A color image with the detected calibration pattern and points on the image overlaid

~detector_cloud (sensor_msgs/PointCloud2)

• (for debugging) A point cloud containing the corners of the checkerboard

~physical_points (sensor_msgs/PointCloud2)

• (for debugging) A point cloud containing the recorded positions of the gripper tip

Parameters

~fixed_frame (string, default: /base_link)

• Fixed frame to use in the calibration. The camera position will be calibrated to this frame.

~camera_frame (string, default: /camera_link)

• Camera frame to use in the calibration. The final calibration will link this frame to the fixed_frame above. Note that this must be the parent of the camera TF tree.

~target_frame (string, default: /calibration_pattern)

• Name of the TF frame to publish the position of the calibration pattern to

~tip_frame (string, default: /gripper_link)

• TF frame for the gripper link. The gripper tip offsets are based off this frame.

~checkerboard_width (int, default: 6)

• Width of the checkerboard. Note that this is the number of inside edges on the width, so this will generally be 1 less than the number of squares on the checkerboard.

~checkerboard_height (int, default: 7)

• Height of the checkerboard. Note that this is the number of inside edges on the height, so this will generally be 1 less than the number of squares on the checkerboard.

~checkerboard_grid (double, default: 0.027)

• Grid size of the checkerboard, in meters.

~gripper_tip_x (double, default: -0.002)

• x offset of the physical tip of the gripper from ~/tip_frame.

~gripper_tip_y (double, default: -0.020)

• y offset of the physical tip of the gripper from ~/tip_frame.

~gripper_tip_z (double, default: -0.0185)

• z offset of the physical tip of the gripper from ~/tip_frame.

Required tf Transforms

<fixed_frame> → <tip_frame>

• Transform from the fixed frame used to the gripper tip link

Provided tf Transforms

<camera_frame> → <target_frame>

• Transform from the camera frame to the calibration pattern