Precision Landing with Companion Computer


I am trying to make use of MAVLINK_MSG_LANDING_TARGET to have my drone do Precision Landing, and i have been making some references with these few links here:

I have not actually flown my drone to see if it works, but i was wondering whether there are parameters/mavlink messages that i can see on mission planner to kind of confirm that the precision landing will actually happen beforehand.

Do the screenshots of these parameters tell me anything?
Screenshot 2021-08-20 153010

My PLND configuration on the Full Parameter List is as such:

Can anyone help to clarify for me if what i have done, and have so far, is a step in the right direction?

Many thanks!

I am using MP 1.3.75 with my drone running on Arducopter 4.0.5

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If you look at my lab picture on the links above, you can see how I make the alignment

HI @ppoirier,

I have seen your lab picture but i am unfamiliar with using SITL through ubuntu and QGroundControl. I have only worked with SITL through mission planner on a windows laptop currently.

Would you be able to advice me on how this can be done using mission planner? For example, may i know where i can get the LANDING_TARGET graph on mission planner of which you have obtained using QGroundControl?

Thank you!

Hello, you can get them by doing Ctrl-F and open the Mavlink inspector but the graphing is not as complete as QGrounControl


Is it possible to make use of this to output mavlink to a udp port so that QGroundControl can connect to MP?


Also, does anyone know if i will get a mavlink message when landing target is acquired/lost/initialised when using arducopter versions that is not the dev version? I see this when i run SITL which uses arducopter v4.2.0-dev

Hi @limzw, you will not get any such messages except after the dev version since 2 days back, when my PR was merged, which sent out those messages…

hi @rishabsingh3003m

I see, thanks for the clarification!

@limzw change PLND_EST_TYPE to 0. Kalman filter is somehow wrong here. It makes drone wobble. RawSensor mode is stable.


Does anyone know what is the earliest firmware version i can work with that can carry out precision landing?

It really depends on how much time you want to invest on getting it to work.

  • ArduCopter 3.5 will probably work, but you will need to invest quite some time debugging and adjusting stuff
  • ArduCopter 3.6 will probably work better, but you will need to invest time debugging and adjusting stuff
  • ArduCopter 4.0 will work better, but you will need to invest a bit of time debugging and adjusting stuff
  • ArduCopter 4.1 will work best, and maybee you will not need to invest a bit of time debugging and adjusting stuff.

Software is not Port wine, it does not get better with age. Use 4.1.0-rc1 or 4.1.0-rc2 that will be released in a couple of days.


hi @amilcarlucas,

Ok, thank you for clarifying!


I have managed to test out precision loiter and it seems to be correcting the position of my drone towards my target, however the drone moves quite violently and abruptly. I have tried adjusting my PID values but it doesn’t seem to help.

May i know what other settings i can or should change to remove this violent behavior?

You should limit the WP_NAV_ACC, and do not change the PIDs

hi @amilcarlucas

Ok thank you! Will try that out next.

Does this mean the drone uses the acceleration and speed that is used during missions when it is correcting itself during precision loiter/landing?

On the ancient ArduCopter 4.0 Version that you are using, yes.

Hi @amilcarlucas

I have tried reducing the WPNAV_ACCEL and WPNAV_SPEED and the drone does move less violently.

Another thing that i’ve noticed is that my drone does not react as quickly when it sees the target, are there settings that i can change to increase the sensitivity? Also, when i feed the angle_x and angle_y in my LANDING_TARGET message, does the flight controller take into account the attitude of the drone?

AFAIK, no.


more chars


Sorry what does more chars mean?

Is there an ideal frequency at which LANDING_TARGET messages are sent to the flight controller also?


The forum requires me to type at leas 20 characters when replying. Those were just to meet that criteria.

Our tests say that 5 to 15Hz is fine

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Ah ok i see :ok_hand:

Ok thanks for clarifying!