Thank you ycheng517 for all the effort you have placed in making the AR4 ROS 2 implementation. I have successfully used the packages you built for my AR4 arm. The only piece that is not working for me is the ar4_hand_eye_calibration package. When I run that package I can successfully gather the calibration data for the camera and I can run the validate script, but my robot will not yet track my arcu marker. The topic is publishing its location but something is wrong with my moveit_py package. I will figure it out, but thought you might like to know someone out there has successfully implemented your work. Thank you again for sharing it.