How to include two or more models in sdf

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Hello everyone, I'm working with PX4 and I'm trying to add two realsense cameras to the iris drone in Gazebo, one pointing forward and one pointing down, but when I include the two models the second camera topics overwrite the first ones. I know this happens because they have the same namespaces but I can't figure out how to distinguish them inside the sdf file in order to have, for example:

• /camera_front/depth/image
• /camera_down/depth/image

The sdf I'm using for the drone is the following:

<sdf version='1.5'>
<model name='iris_realsense'>

<include>
<uri>model://iris</uri>
</include>

<include>
<uri>model://r200</uri>
<name>front_camera</name>
<pose>0.2 0 0 0 0 0</pose>
</include>

<include>
<uri>model://r200</uri>
<name>down_camera</name>
<pose>0 0 -0.05 0 1.57 0</pose>
</include>

<joint name="fpv_cam_joint" type="fixed">
<axis>
<xyz>0 0 1</xyz>
<limit>
<upper>0</upper>
<lower>0</lower>
</limit>
</axis>
</joint>

<joint name="fpv_cam_joint2" type="fixed">
<axis>
<xyz>0 0 1</xyz>
<limit>
<upper>0</upper>
<lower>0</lower>
</limit>
</axis>
</joint>

</model>
</sdf>


and the realsense sdf included is:

<plugin name="r200_controller" filename="libgazebo_ros_camera.so">
<ros>
<namespace>custom_ns</namespace>
<argument>custom_camera/image_raw:=custom_camera/custom_image</argument>
<argument>custom_camera/image_depth:=custom_camera/custom_image_depth</argument>
<argument>custom_camera/camera_info:=custom_camera/custom_info_raw</argument>
<argument>custom_camera/camera_info_depth:=custom_camera/custom_info_depth</argument>
<argument>custom_camera/points:=custom_camera/custom_points</argument>
</ros>
<frameName>r200</frameName>
</plugin>