Gazebo classic SILT Simulation, gazebo real time factor in blanck

Hello, everyone

Lately i’ve been working on SITL simulations with the typhoon model and also with a custom drone model. But i’ve noticed a weird behavior on the simulations.

Sometimes, in the Gazebo IDE, the simulations actually show a realtime factor (which i get in 1or very close to 1) and display a simulation and real time, as well as the fps. However, some other times those values are never displayed and the cases are in blank.

I have noticed that when this happens, the video streaming button of the typhon doesnt appear…
and with the custom model, the Gazebo GUI camera is not set as i did.

i used VERBOSE_SIM=1 when lounching the sitl simulation to check if there were any silent fails, but everything seems ok…

the only warning i get is this one
[Wrn] [Event.cc:61] Warning: Deleting a connection right after creation. Make sure to save the ConnectionPtr from a Connect call

Additionally i get this warning:
WARN [health_and_arming_checks] Preflight Fail: ekf2 missing data

But this one usually appears in both scenarios (times appear and do not appear) and after a coulple of seconds its passed and i can arm and even takeoff.

I read someone saying that lost some realtime factor because the order of the imported plugins in the models sdf. i double checked and have the exact same order as in the Iris model.

Any help is welcomed.
Thank you so much
Captura desde 2025-05-18 11-09-25

I think I have seen this intermittent problem as well in the past. I wouldn’t hold my breath for a fix given Gazebo Classic is no longer maintained and everyone is meant to move on to new Gazebo.

Thats sad. Any suggestions or advice on how to improve this? im currently using classic and cant really migrate to new Gazebo right now.

Despite this problem im able to do offboard control in SITL simulation and use stamped ros2 nodes. Do you believe this may deeply affect simulation results?

Thank you so much!
Best regards