[mavros_extras] Using image bridge when UDP link to GCS already active

[TSC21]

(suggested by @mhkabir)

If I have a proxy link from mavros to QGC using UDP (sending data from PX4), is it possible to send image data using the same link?

Also, please can you add launch files for image_bridge.

[vooon]

Please add chain what you want (don't understand what node provide UDP bridge).

[TSC21]

This is a @mhkabir issue so it's probably better that he answers. Don't know if I'll be using this plugin either (can use it to px4flow or to any other camera though).

[vooon]

Oh, i forgot add @mhkabir first :).

[mhkabir]

Sorry, I must have overlooked this.

Basically, say we have UDP link to GCS active , streaming data from connected PX4. Can, we stream video using the same link to GCS, instead of separate link?

[vooon]

UDP link opened by mavros or external node (gcs_bridge)?

If by mavros - not, you must disable internal bridge by setting _gcs_url:='' and use gcs_image_bridge for GCS link.

E.g.

roslaunch mavros px4.launch fcu_url:='...' gcs_url:=''
rosrun mavros_extras gcs_image_bridge _gcs_url:='...'

[mhkabir]

I mean opened by mavros. It would be good if we could use same link for
image and mavlink stream (IMU,position, etc.) to GCS.

:(

On Thu, Aug 14, 2014 at 5:34 PM, Vladimir Ermakov notifications@github.com
wrote:

UDP link opened by mavros or external node (gcs_bridge)?

If by mavros - not, you must disable internal bridge by setting
_gcs_url:='' and use gcs_image_bridge for GCS link.

E.g.

roslaunch mavros px4.launch fcu_url:='...' gcs_url:=''
rosrun mavros_extras gcs_image_bridge _gcs_url:='...'

—
Reply to this email directly or view it on GitHub
#103 (comment).

[vooon]

But gcs_bridge provide all streams from mavros (IMU, position etc.).

It works similar way as internal, except it adds communication via ros topics to/from.

[mhkabir]

So how do we stream all data from mavros + images to same GCS?

Example please :)

On Thu, Aug 14, 2014 at 6:03 PM, Vladimir Ermakov notifications@github.com
wrote:

But gcs_bridge provide all streams from mavros (IMU, position etc.).

—
Reply to this email directly or view it on GitHub
#103 (comment).

[vooon]

I write launch for that.

[mhkabir]

Working fine now. Some issues with freezing, and I think this is on mavros side. I'll see what I can do.

@vooon I need to know ASAP, how do I set the pose_with_covariance parameter to true from a launchfile? I have tried many combinations, but for some silly reason, it refuses to set.
Please let me know roslaunch syntax for this :)

[vooon]

Add to <node>:

<param name="position/vision/pose_with_covariance" value="true" />

[mhkabir]

@vooon Not working :(

rosparam list gives this :

/gcs_image_bridge/gcs_url
/gcs_image_bridge/position/vision/pose_with_covariance
/mavros/conn_heartbeat
/mavros/conn_timeout
/mavros/fcu_url
/mavros/gcs_url
/mavros/plugin_blacklist
/mavros/startup_px4_usb_quirk
/mavros/target_component_id
/mavros/target_system_id

Node has this :

    <node pkg="mavros_extras" type="gcs_image_bridge" name="gcs_image_bridge" clear_params="true" output="screen">
        <remap from="/mavlink/gcs_image" to="/svo/image" />
        <param name="gcs_url" value="$(arg gcs_url)" />
        <param name="position/vision/pose_with_covariance" value="true" />
    </node>

[TSC21]

<param name="position/vision/pose_with_covariance" value="true" /> it's a parameter from mavros and not mavros_extras.
So try: <param name="mavros/position/vision/pose_with_covariance" value="true" />
or add this parameter to mavros_node instead:

<node pkg="mavros" type="mavros_node" name="mavros" required="true" clear_params="true" output="screen">
    ....
    ....
    ....
    <param name="position/vision/pose_with_covariance" value="true" />
    ....
</node>

[vooon]

@TSC21 right!

Note: you can use rosparam get / to view all parameters with it's values.

[mhkabir]

Cool thanks guys :D Working now :D

[mhkabir]

@vooon The image sending system still has some problems, as I can see. Sometimes, QGC freezes up with the stream. Any idea why. There are debug messages in QGC relating to JPEG errors, can you please check up on this a bit?

Kabir

[vooon]

As i mentioned before QGC sometimes drop images (with errors in terminal).

I don't know why, and think bug in QGC, because my image_pub plugin works fine.

You can construct this chain:

image node -ros-> gcs_image_bridge -udp-> mavros -ros-> rqt_image_view
                                                 -udp-> QGC

Or can you check px4flow camera launch?

roslaunch mavros_extras px4flow.launch gcs_url:=udp://@localhost
rqt_image_view

Then connect QGC to UDP and check video stream in both QGC and RQT.

[vooon]

I think we can close this issue?

[mhkabir]

Yep.