Hi, I am working on a project on Delta robot too. How did you manage to write the xacro file correctly? I don't know how to connect the end-effector to the 3 forearms (since xacro/urdf do not support parallel linkages). Moreover, I don't know how to build the non actuated joints (ball joints) since these type of joints is not supported by xacro/urdf. Any help would be greatly appreciated!