Time synchronization issue crazyflie + SLAM

[wladimirpetrov]

Hello,

I am experiencing an issue with SLAM integration while using Crazyswarm2. Specifically, when running SLAM Toolbox with my Crazyflie (configured with a multiranger and flowdeck), I intermittently encounter the following error in the async_slam_toolbox_node, whe i run:
ros2 launch crazyflie_examples multiranger_mapping_launch.py
most of the time i get:
[async_slam_toolbox_node-3] [INFO] [1736953066.756381739] [slam_toolbox]: Message Filter dropping message: frame 'cf231' at time 1736953066.556 for reason 'discarding message because the queue is full' [async_slam_toolbox_node-3] [INFO] [1736953066.956146067] [slam_toolbox]: Message Filter dropping message: frame 'cf231' at time 1736953066.756 for reason 'discarding message because the queue is full'
So i decided to decrease the frequencies in crazyflie.yaml (for testing) and then I got the following:
crazyflie [slam_toolbox]: Message Filter dropping message: frame 'cf231' at time 1736888194.835 for reason 'the timestamp on the message is earlier than all the data in the transform cache'
Which is from my understanding is a quite common SLAM issue even with turtlebots.

My question is: What onboard mechanism or feature does the Crazyflie have to synchronize its time with the host PC, similar to how Turtlebot uses time synchronization methods like NTP?

[gemenerik]

It seems like you might be asking your Crazyswarm question in the wrong repo again. However, if you believe this is related to our source code, feel free to clarify. In Crazyflie-lib, we don’t handle time synchronization.