Interfacing with Gazebo during SITL

Hi there.

I’m looking to send my own sensor readings to the PX4 during SITL. I thought I could use the “Simulator MAVLink API” by sending MAVLink messages such as HIL_SENSOR, HIL_OPTICAL_FLOW, HIL_GPS, etc. to TCP port 4560 but it doesn’t appear to be working. Is there another way to send raw sensor values to PX4 during SITL? This is for a research project.

This is what I’m referencing: