The publishers are created in the main unitreevision class
exts/omni.isaac.quadruped/omni/isaac/quadruped/robots/unitree_vision.py
if you look at the og.Controller.edit section you can see how RGB publisher was created and configured.
(camera_graph, _, _, _) = og.Controller.edit(
{
"graph_path": "/ROS_" + camera[0].split("/")[-1],
"evaluator_name": "push",
"pipeline_stage": og.GraphPipelineStage.GRAPH_PIPELINE_STAGE_ONDEMAND,
},
{
keys.CREATE_NODES: [
("OnTick", "omni.graph.action.OnTick"),
("createViewport", "omni.isaac.core_nodes.IsaacCreateViewport"),
("setActiveCamera", "omni.graph.ui.SetActiveViewportCamera"),
("cameraHelperRgb", "omni.isaac." + ros_bridge_version + ros_version + "CameraHelper"),
("cameraHelperInfo", "omni.isaac." + ros_bridge_version + ros_version + "CameraHelper"),
],
keys.CONNECT: [
("OnTick.outputs:tick", "createViewport.inputs:execIn"),
("createViewport.outputs:execOut", "setActiveCamera.inputs:execIn"),
("createViewport.outputs:viewport", "setActiveCamera.inputs:viewport"),
("setActiveCamera.outputs:execOut", "cameraHelperRgb.inputs:execIn"),
("setActiveCamera.outputs:execOut", "cameraHelperInfo.inputs:execIn"),
("createViewport.outputs:viewport", "cameraHelperRgb.inputs:viewport"),
("createViewport.outputs:viewport", "cameraHelperInfo.inputs:viewport"),
],
keys.SET_VALUES: [
("createViewport.inputs:viewportId", i + self.ros_vp_offset),
("setActiveCamera.inputs:primPath", camera_path),
("cameraHelperRgb.inputs:frameId", camera[0]),
("cameraHelperRgb.inputs:nodeNamespace", "/isaac_a1"),
("cameraHelperRgb.inputs:topicName", "camera_forward" + camera[0] + "/rgb"),
("cameraHelperRgb.inputs:type", "rgb"),
("cameraHelperInfo.inputs:frameId", camera[0]),
("cameraHelperInfo.inputs:nodeNamespace", "/isaac_a1"),
("cameraHelperInfo.inputs:topicName", camera[0] + "/camera_info"),
("cameraHelperInfo.inputs:type", "camera_info"),
],
},
)