Get Camera Extrinsic Parameters to set Custom Coordinate Space

[ravijo]

Hi,

I couldn't find much information about custom coordinate space. Basically, I want to set my coordinate space outside the checkerboard. I have the transformation information as shown below:

<node name="tf_box_to_marker" pkg="tf2_ros" type="static_transform_publisher" args="1 1 0 0 0 0 box marker" />

This is how my phoxi_camera.yaml file is looking right now:

frame_id: "marker"
coordinate_space: 3

I think the parent frame for custom coordinate space is located in the camera and the child is going to be the box. Therefore, if I can get the current camera extrinsic parameters, I can do a simple matrix calculation to get the overall transformation.

How to get camera extrinsic parameters to set a custom coordinate space?