Local ENU orientation.

[GeoGk]

Hello,

I am trying to retrieve certain data from different fixposition topics in order to construct a GeoPoseWithCovariance message.
I need the orientation (in quaternion) between FP_POI and the local ENU. Looking at the documentation I see that orientation is provided in ENU0 (amongst other frames) which is not what I am looking for since this frame is a global fixed one.
The /fixposition/ypr topic in its description mentions that it is the orientation of FP_POI with respect to ENU.
Is this ENU a local one?
If not is there a way to get this data without transforming the orientation from another already provided frame?

Thank you in advance.

[flipflip8952]

No frame/geometry or ROS expert, but perhaps the documentation on the sensor output messages [1] such as FP_A-ODOMENU [2] or FP_A-TF [3] can shed some light? Maybe the data isn't directly available the way you want, but the sensor should output all necessary information for you to do the transformation you need yourself.

[1] https://docs.fixposition.com/fd/fp_a-messages
[2] https://docs.fixposition.com/fd/fp_a-odomenu
[3] https://docs.fixposition.com/fd/fp_a-tf

[GeoGk]

Thank you for your answer.
I am aware that the necessary data for the transformation are already in the published messages, I have already read the documentation on the suggested links, but as I mentioned in my question I would like to avoid doing the transformation myself if the data I am looking is already provided somewhere where I might not be aware of.
I am mainly wondering what kind of frame ENU is in the description of the /fixposition/ypr topic (that can be found in the documentation).
Is that just a typo, where ENU was supposed to be ENU0 or is this actually a local ENU (as opposed to the global fixed ENU0) from which the roll/pitch/yaw angles are calculated from?

[flipflip8952]

I'm confused, too. I'm not sure what exactly is the intention of the /ypr topic. The documentation isn't clear enough I think.
@fixposition-support please enlighten us.

[fgarciacardenas]

Hello @GeoGk. The '/fixposition/ypr' topic outputs the sensor's orientation w.r.t. ENU0, thank you for spotting the typo. To obtain the local ENU orientation, you could use the inspvax topic, but you still need to convert it to quaternion. Alternatively, you could use the function RotEnuEcef() from trafo.hpp to compute the local ENU frame.

[GeoGk]

That's what I was looking for. Thank you for the clarification and the suggestions.