Hello @LorenzMeier , @Jaeyoung-Lim , @JonasVautherin , @JulianOes . I have tried the procedure to create custom mavlink message and send it from MAVROS to PX4 simualtion instance from “ Sending Custom Messages from MAVROS · PX4 Developer Guide ”. I face the following error when i build MAVROS again afte…

Ya, that’s not gonna work an unsigned char can not become a mavlink_message. That example in the docs seems to be wrong. Try something like this: void send_to_pixhawk(char cmd) { mavlink_message_t msg; mavlink_msg_key_command_pack_chan(UAS_PACK_CHAN(uas), &msg, cmd); …

Hello @jimdgit , @TSC21 , I followed what you told, i got the following error: [Screenshot from 2020-10-08 23-40-17] My keyboard_command.cpp file is as follows: #include <mavros/mavros_plugin.h> #include <pluginlib/class_list_macros.h> #include <iostream> #include <std_msgs/Char.h> //#include <…

try including: mavlink.h But look this code was bugged from the start and I can’t find the source file for it Also you seem new to c++ so this will no doubt be a heavy lift. If it does not work I will have no idea why, I just know you can’t cast a char to a struct. Perhaps @JulianOes will jump …

hello @jimdgit , thanks for your quick replies. I would like to say that mavlink_message_t struct is already included via mavros_plugin.h in the file keyboard_command.cpp. I would like to include @JulianOes , @Vladimir_Ermakov o look into the code for a second. My plugin file looks like: #inclu…

As I have tried to explain this example is obsolete. Please choose another example from: [image] mavlink/mavros MAVLink to ROS gateway with proxy for Ground Control Station - mavlink/mavros as your starting point. They will at least build and if you study th…

OKay, thanks @jimdgit , i will try some of them suggested by you. :slightly_smiling_face:

Also look at: [image] mavlink/mavros MAVLink to ROS gateway with proxy for Ground Control Station - mavlink/mavros

I am also following the same example and receiving the same error message as OP. Has there been any movement in correcting the root cause and pushing the fix? A working end-to-end tutorial is extremely valuable.

I believe I’ve identified the problem with this example. The current version of the example is not packaging the input into the KEY_COMMAND message the user created in the common.xml file. Using the following definition of the keyboard_cb function compiles successfully. void keyboard_cb(const st…

I now have the complete functionality working. The current version of the tutorial is way out of date. I found the following issues while working through it: The callback function ‘keyboard_cb’ is missing steps to create a msg and add data to the field (see above post) The CMake file for the keybo…

Error while data type conversion from "Unsigned char" to "Const mavlink" {aka mavlink message type}

MAVLink

Ranjeet October 9, 2020, 6:47pm 7

OKay, thanks @jimdgit, i will try some of them suggested by you.

Topic		Replies	Views
Issues Running ROS2-PX4 ROS 1 / ROS 2	25	2712	October 23, 2025
No such file or directory <uORB/topics/sensor_combined.h>	8	3954	November 19, 2017
PX4 Dev Call: November 23, 2022 PX4 Autopilot	6	666	December 1, 2022
Offboard control using ROS2 ROS 1 / ROS 2	10	3725	July 15, 2022
Error in keyboard_command.cpp Sending custom messages from mavros to PX4 PX4 Autopilot	6	333	January 16, 2024

Error while data type conversion from "Unsigned char" to "Const mavlink" {aka mavlink message type}

Related topics