matlab publish to ros2 wrong

when i follow the article https://ww2.mathworks.cn/help/ros/ug/control-a-simulated-uav-using-ros2-and-px4-bridge.html

i found that when i use the code or simulink model to send /fmu/in/vehicle_command. and then i get the response

response:

timestamp: 1764851141943341

param1: 1.0

param2: 6.0

param3: 0.0

param4: 0.0

param5: 0.0

param6: 0.0

param7: 0.0

command: 176

target_system: 1

target_component: 1

source_system: 1

source_component: 256

confirmation: 0

from_external: false

code:

node = ros2node("/control_node");

% General information about the UAV system

controlModePub = ros2publisher(node,"fmu/in/offboard_control_mode","px4_msgs/OffboardControlMode");

statusSub = ros2subscriber(node,"/fmu/out/vehicle_status","px4_msgs/VehicleStatus","Reliability","besteffort");

timeSub = ros2subscriber(node,"/fmu/out/timesync_status","px4_msgs/TimesyncStatus","Reliability","besteffort");

% Sensor and control communication

odomSub = ros2subscriber(node,"/fmu/out/vehicle_odometry","px4_msgs/VehicleOdometry","Reliability","besteffort");

setpointPub = ros2publisher(node,"fmu/in/trajectory_setpoint","px4_msgs/TrajectorySetpoint");

cmdPub = ros2publisher(node,"/fmu/in/vehicle_command","px4_msgs/VehicleCommand");

cmdMsg = ros2message(cmdPub);

cmdMsg.command = uint32(cmdMsg.VEHICLE_CMD_DO_SET_MODE);

cmdMsg.param1 = single(1);

cmdMsg.param2 = single(6);

publishVehicleCommand(timeSub,cmdPub,cmdMsg)

function publishVehicleCommand(timeSub,cmdPub,cmdMsg)

cmdMsg.timestamp = timeSub.LatestMessage.timestamp;

cmdMsg.target_system = uint8(1);

cmdMsg.target_component = uint8(1);

cmdMsg.source_system = uint8(1);

cmdMsg.source_component = uint8(1);

cmdMsg.from_external = true;

send(cmdPub,cmdMsg)

end

the from_external and source_component is different, and i don't know why.

[雨蒙]

may be it is not a question, PX4 would chagne it auto.

however, ifound the reason why i can't control my UAV stability.

i set the param in simulink like this.

when i see the result in wsl2, i found the frequency is 1HZ as follow:

The PX4 request >2HZ, so it result the question .

and i don't know how to deal it.

Answer 1

[雨蒙]

And I have another question: when I control the UAV in Offboard mode using Simulink, I get the following error:

I followed the suggested solution from this post—increasing the COM_OF_LOSS_T parameter value:

https://discuss.px4.io/t/multi-tethered-drone-error-matching-flight-task-was-not-able-to-run/32993

It seems to help!

However, I’m still not sure what’s causing the issue. It looks like there might be a problem with the publishing rate or timing in my Simulink setup.