Giving Up on Auto Landing

That’s what TECS_SPDWEIGHT and TECS_LAND_SPDWGT control. Have you modified those to try?

I’ve done quite a bit of autolanding work. I may be able to help figure out the issues you’re seeing. Can you upload a log from the SD card from a flight with a overshot landing? And also a log where you did a successful manual landing.

… no I havent. Have been pretty hesitant to mess with or change anything about those. I read -1 would let it scale automatically and probably the best option.

i think I read else where you were suggesting a number (1.4 maybe?) to someone else - have been considering changing these parameters (just hesitant).


Sure will however it will have to wait as I am out of town for a couple weeks (yes - a total bummer).

I can promise they won’t result in your plane falling out of the sky. As always, have FBWA and/or MANUAL mode as a backup and switch to it if you see a dangerous flight condition. Those parameters are commonly changed.

In the manned aviation world during slow flight, we say “Pitch for airspeed, power for altitude.” That doesn’t work so well in cruise where your primary finite altitude control is pitch, not power. During landing, however, it works relatively well. That’s why I suggest increasing those parameters for landing.

The parameter descriptions are poor, and honestly partially incorrect. I think the descriptions will change in the future. Remember you should always have stick override without switching modes. This can really help you guide in the landings when the tune isn’t quite right yet.

Naterater - thank you very much.
I as soon as I can get back to it I will work those params as well.

I will circle back to this posting and comment on the results.

Useless to try autolanding without lidar. The barometric altitude is prone to drift and even 2 or 3 meters difference will already have a huge effect. Try SF11B from Lightware.

OR RTK in my opinion. Yes, barometric pressure can change a few meters just due to pressure inside the fuselage during flight.

So then …

Which is the most straight forward process in regards to implementation (Lidar or RTK)?

What guides or discussions are available when attemping to implement either of these (more precise solutions) directly related to autolanding?

I love the ardupilot project and recognize the effort and dedication of many people (thanks!), but sincerely I can’t understand things like this. How much time takes to changing or improve a parameter description? 5 minutes on the worst case?

I’ve been working on that in my spare time. Some of the main ones are improved, and if you want to collaborate, I would be happy to work with you. Here was my first update a few weeks ago.

In addition, I recommend you leave a comment here about standardizing these conventions:

What RTK are you using? Emlid Reach? Are you using a LIDAR as well?

I am interested in auto-landing as well. I would have assumed an accurate LIDAR would be better than RTK. Why did you choose RTK?

I chose RTK because I need constant altitude reference that does not drift over long flights when I do mapping. My takeoff and landing locations are the same, so I do not need any terrain information from a lidar. Lidar would be better than RTK if you were not certain of your landing site in advance.

I am using the Here+ for navigation RTK, and the Emlid Reach for a backup non-rtk system. I am logging the Emlid Reach for PPK purposes.

Hi Matt, Can I ask about your Lidar V3 setup? I have a Garmin V3 wired to I2C as described in the wiki with the capacitor and I get a reading of 996 in cm and a Sonar Altitide fluctuation from 0 to 30. I set the airceaft height to 30cm and tge max alt to 4000 meters. Sepwrate power supply of 5.5 volts. Any assistamce appreciated. Perhaps I should start a new thread.

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