COMMAND_ACK - result: 4 --- how to debug

Ground Control Software MAVLink
1

Hi All,

How do we debug “result: 4” acks from Pixhawk2.4.8 for a Mavlink command.

My setup is the following:

Frame: QUAD
Pixhawk1 002C001A 3337510D 31313639
ChibiOS: 57801550
ArduCopter V3.7-dev (1c3d90d8)

I am using a Pixhawk 2.4.8 with a RPi3b as a companion computer. Mission planner is 1.3.59

My command on the companion computer is the following:
mavproxy.py --master=/dev/ttyAMA0 --baudrate 57600 --out=udpin:192.168.137.91:14550

I would like to understand why the “result: 4” shows up for my takeoff 15 command. I set moddebug to 3 hoping to get some explicit messages along with result: 4.

ALT_HOLD>
ALT_HOLD> set moddebug
ALT_HOLD> moddebug 3

ALT_HOLD> arm throttle
ALT_HOLD> Got MAVLink msg: COMMAND_ACK {command : 400, result : 0}
ARMED
Arming checks disabled

ALT_HOLD> takeoff 15
ALT_HOLD> Take Off started
Got MAVLink msg: COMMAND_ACK {command : 22, result : 4}
DISARMED

1 Like
2

Hi dronetail,
Did you find a solution? I am facing the exact same problem…

3

hi did u found something i have the same problem here i don-t know what to do next I want to graduate before 10 of may 2019 help please

4

Facing the same problem mate!
Any idea on what the result codes mean?

5

Why not read the mavlink documentation?
if you do so you can find out that the ACK:4 means NOT_SUPPORTED (https://mavlink.io/en/messages/common.html#MAV_CMD_ACK_ERR_NOT_SUPPORTED)
Which is quite understandable since in ALT_HOLD mode you cannot issue Takeoff command.
The correct way to do it is to switch to GUIDED mode than arm and issue takeoff…