I'm mapping with the SLAMTEC LIDAR :) Is there an urdf file for the Create3 with LIDAR and OAK-D Light ?

[jerrynsr]

Hi,
I was wondering if an urdf file exists for the iRobot Create3. The LIDAR example works great, now I would like to move on to NAV2. Should I search for the Turtlebot 4 examples and start from there ?

[shamlian]

There is a urdf file for Create 3, but we have not published one with arbitrary sensors. You don't need a urdf on a real robot; you can use the tf frames that Create 3 publishes in combination with extra publishers you write to reference your sensors' coordinate frames to the robot.

[jerrynsr]

Is there a good reference to use to convert a urdf defined for Gazebo for use with a physical robot ?

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[justinIRBT]

There is a robot_state_publisher described here:
https://docs.ros.org/en/foxy/Tutorials/URDF/Using-URDF-with-Robot-State-Publisher.html
but I think that might be overkill for what you are trying to accomplish.
The easiest path to get the camera into your TF tree would be to just use a static_transform_publisher similar to what was done for the laser here:
https://github.com/iRobotEducation/create3_examples/blob/galactic/create3_lidar/launch/sensors_launch.py#L11
I haven't used the OAK-D, but something to watch out for is which tf frames the OAK-D driver is publishing it's data with respect to (what is in the message header.frame_id), as the image frame might be rotated with respect to the robot. As an example, when working with the Intel Realsense, I had to use the following frames:

Node(package='tf2_ros', executable='static_transform_publisher',
            arguments=['-0.03', '0.0', '0.19', '0', '0.03', '0.0', 'base_link', 'camera_link']),
Node(package='tf2_ros', executable='static_transform_publisher',
            arguments=['0.0', '0.03', '0.0', str(-math.pi/2), '0', str(-math.pi/2), 'camera_link', 'camera_depth_optical_frame']),

Where the camera_depth_optical_frame was published by the realsense driver and had a 90 degree offset. Combining the base_link->camera_link modeling the camera's physical position on the robot with camera_link->camera_depth_optical_frame put the depth data at the correct position/orientation in base_link.

[alsora]

+1 on this.
You don't need urdf on real robots.

The create 3 is already publishing TF frames describing the robot, you only need to create extra publishers for the accessories/frame that you attached to it.

[jerrynsr]

I'm looking for how to add the Slamtec a-1 to the urdf

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