ENU and NED frames in mavros

ROS / MAVROS / MicroDDS
1

Hi, guys.

PX4 drone take its frame to be NED, while we prefer ENU frame in robotics.

But I am still confused in push mocap infor to vision_pose and send position setpoints to mavros/setpoint_raw/local and mavros/setpoint_position/local.

If I do

  1. pub mocap infor in ENU to /mavros/vision_pose/pose ,
  2. pusb reference position in NED, takeoff 1m means (0,0,-1), to mavros/setpoint_raw/local,

then, what I get is “INFO [commander] Disarmed by auto preflight disarming” in simulation. (edited)

Interestingly, if I do

  1. pub mocap infor in ENU to /mavros/vision_pose/pose ,
  2. pusb reference position in ENU, takeoff 1m means (0,0,1), to mavros/setpoint_raw/local or mavros/setpoint_position/local..

It does take off and hover in simulation.

Does mavros automatically accepts/publish infro in ENU, and transfer them into NED to NED? Does it mean, we do not need to brother?

2

Hi!

Yes, mavros takes care of frame conversions.
You can see it here: https://github.com/mavlink/mavros/blob/686bd833e7d6ea5542977178872762dfbec5ed89/mavros/src/plugins/setpoint_raw.cpp#L212 regarding setpoint_raw and here https://github.com/mavlink/mavros/blob/686bd833e7d6ea5542977178872762dfbec5ed89/mavros/src/plugins/setpoint_position.cpp#L130 regarding setpoint_position.

3

Hi, Benja. Thanks so much for your reply. I read the links that sent by you.

Just to be sure:
In terms of setpoint_raw/local, should I leave coordinate_frame () empty when I pub commands in ENU, such that it will run position = ftf::transform_frame_enu_ned(position) in line 223?

But for setpoint_position/local , the message (geometry_msgs/PoseStamped) does not have a coordinate_frame for us to specify like mavros_msgs/PositionTarget for setpoint_raw/local. What should I do for using mavlink::common::MAV_FRAME in order to use ENU? Or It is set to be the ENU frame by default?

4

Hi Robin,

I’ll try first setting coordinate_frame to FRAME_LOCAL_NED (see the message characteristics).

For setpoint_position/local, mavros should take care of everything.

Maybe you could try everything in simulation with gazebo, to be super sure :wink:

5

Thanks for your message.
I just tested both in gazebo simulation.
From the simulation results, we can send commands in ENU to them :grinning:.
I will test them in real experiments soon.