Logging external positions

[danteppc]

Hello,

I am trying compare positions from a swarm of Crazyflies in UWB-TDoA mode, with true positions from a mocap system. That means I want the drones to only use UWB for flying but also record data from mocap.

I understand I can use something like libmotioncapture and record the ground truth while using Crazyswarm in UWB mode for drones, but I thought maybe logging positions at Crazyflie in crtp_localization_service.c might have the advantage of not needing to worry about synchronization of UWB positions with mocap positions when doing a comparison.

However I see no such functionality in Crazyswarm, that means If I keep motion capture enabled in the config file, the Crazyflie will mocap positions for controlling the drone.

Or maybe I am missing something?

thank you

[whoenig]

Two options:

1. Change the firmware to not send the mocap data to the Kalman filter and record data on-board using the uSD card deck.
2. Execute the motion_capture node manually (i.e., not using the default launch file in Crazyswarm2), or remap the /poses topic to a different name.

[danteppc]

I used the uSD and changed the crazyflie firmware to not push extPose to the kalman filter. It worked. I observed something perhaps worth mentioning: the body frame for CF on rviz is now flickering we guess because stateEstimate is based on uwb even though mocap is enabled in the config file.

[whoenig]

Probably related to #235 ?