Could not receive uXRCE-DDS messages through TELEM2 with serial port on companion computer

[xirhxq]

Autopilot Setup

According to official document

• Set MAV_1_CONFIG to 0.
• Set UXRCE_DDS_CFG to 102(TELEM2).
• Set SER_TEL2_BAUD to 921600.
• In MAVLink Console run uxrce_dds_client stop then uxrce_dds_client start -t serial -d /dev/ttyS1 -b 921600.
• Reboot Vehicle in QGroundControl.

Environment Setup on Companion Computer

• Install ROS2 Foxy
• Install uXRCE_DDS agent by Step 3 of here.
• Build ROS2 workspace with px4_msgs and px4_ros_com.

Problem

On companion computer run sudo MicroXRCEAgent serial --dev /dev/ttyTHS0 -b 921600 and I only got this:

amov@amov-desktop:~$ sudo MicroXRCEAgent serial --dev /dev/ttyTHS0 -b 921600
[1741267380.825678] info | TermiosAgentLinux.cpp | init | running... | fd: 3
[1741267380.826487] info | Root.cpp | set_verbose_level | logger setup | verbose_level: 4

and running ros2 topic list I got nothing more than /rosout and /parameter_events.

Some Other Things

Check with serial connection

I ran cutecom to see the incoming data of /dev/ttyTHS0, then I got:

It seems like there are incoming data frames (starts with 7e 01 and ends cf 12) coming in with ~1hz. So I guess the wire connection was right.

Trials with Other Baud Rates

I read this and tried to set Baud rates with TELEM2 to either 57600, 115200 and 1000000. All of them cause same result. The change of baud rate including these steps(115200 for example):

• Change SER_TEL2_BAUD to 115200.
• In MAVLink Console run uxrce_dds_client stop then uxrce_dds_client start -t serial -d /dev/ttyS1 -b 115200.
• Reboot vehicle in QGroundControl.
• On companion computer run sudo MicroXRCEAgent serial --dev /dev/ttyTHS0 -b 115200.
• Try with cutecom to see the data coming to /dev/ttyTHS0.

Basic Configuration

Parameters

In case other parameters need to be examined, I saved a .params file here.

The Most Weird Thing

I have used the SAME companion computer to receive the ROS2 topic data with another vehicle. Here is the brief information about it:

• Model: AmovLab P450 Quadrotor.
• Controller: Pixhawk6C
• Firmware Version: 1.15.4
• Link: here
• PX4 Params: here
• Wire Connections: TELEM2 on Pixhawk6C <—> UART1 on Amov NX

So I guess my companion computer was set right.

Summary

Basically, I’ve encounter problems with receiving uXRCE messages from a VTOL with CubePilot Cube Orange+ using a companion computer that has already succeeded with another quadrotor with Pixhawk6C. I have ruled out (in my mind) problems with wire connections and companion computer. I guess it has something to do with settings with CubePilot Cube Orange+.

I hope someone can help. I am pretty desperate about this. If someone is reading documents with AmovLab devices, they are in Mandarin and I recommend to translate it by web browser.

Wish all the best