I am trying to modify the VIO algorithm. I was going through the PX4 documentation: Using Vision or Motion Capture Systems for Position Estimation. They mentioned that in order to add the VIO data in the EKF2, it needs to be published either in "/mavros/vision_pose/pose" or "/mavros/odometry/out". I launched the voxl_mpa_to_ros and px4 launch files, here is the all available rostopics:

I set the QGC parameters as follows:

But there is nothing that's being published in both those topic. So I am wondering how is the VIO data being send to PX4 to get it fused with EKF2. I can see the ODOMETERY data through the MAVLink Inspector, but through mavros. I tried moving the UAV manually in the lab and plotted the position data from the "/qvio/pose" and "/mavros/local_position/pose". Here are the plots:

As per the mavros documentation "/mavros/local_position/pose" published fused pose which means the PX4 infact fusing the VIO pose estimates. So, can anyone explain how?

@張為超 It worked. I setup my Pc as the master this time, and it worked in that way.

@張為超 Yes it does. Voxl2 is the master. I am running the voxl mpa to ros node in voxl2 and then trying to echo the published topics in my PC.

I wrote a subscriber node to get the ‘data’ field of the ‘sensor_msgs/Img’ for rostopic ‘/tracking’. But not getting any output. I even tried echoing the topic, but still no output. Can someone explain the reason? The required services are already enabled and running.

I was trying to subscribe to the published topics voxl_mpa_to_ros node but not getting any data. I even tried echoing the topics, but no output. What am I missing here?