IRLOCK makes copter hover 1 m above target during landing

Hi,

I’ve been using my IRLOCK a couple of months and it works really fine (the landing accuracy is around 30 cm as advertised). However, when I use it in a bigger quad with large propellers (20x6.1), I always have the same issue: when the IRLOCK detects the beacon, the quad centers above it and continues its descent. Around 1 m, the copter hovers as if the IRLOCK wasn’t sure of the beacon presence (sometimes it goes up a couple of cm) and after some seconds it finally lands.

This has to do with the logic of the IRLOCK, because when I don’t use the beacon, the copter lands smoothly without hovering during descent (of course without the beacon it lands in the home point just based on the GPS).

A couple of remarks:

  • The landing speed is 1 m/s above 10 m.
  • Below 10 m, the landing speed is 0.35 m/s. I’ve found from a lot of testing that I can reliably detect the beacon at that speed.

I have attached a video of the behavior and the log of the corresponding flight.

Thanks a lot!

Javier

Youtube video
Bin file

Hi,

Does anybody have an answer to this? It keeps happening to me, it’s been almost a month and I still don’t know why.

Best,

Javier

We had a similar prob on a big quad with big props.

We solved it enabling a param called “gnd_effect_comp” to 1

Let me know if solved.

regards,

Corrado

1 Like

Hi,

This didn’t work. I guess this parameter only works to land when using short landing gear, mine is the regular one.

Best,

Javier

Same behavior for me. I don’t think that this has something to do with the prop size, mine is a 12” quad.
Agree it would be great if there was a parameter to adjust the landing speed once the copter came down to 1 m with IR Lock.

Hi,

Just out of curiosity, what rangefinder are you using? One possibility is that we’re getting false readings and that’s why it takes so much to land.

Best,

Javier

Nevermind, I just discarded that.

@ThomasSFL, could you check this, please? I’ve made some flights last week, this time using a LidarLite rangefinder. As you can see in my logs, the rangefinder works up to 40 m, and the beacon was detected up to 20 m in air without issues. However, the same thing happened: at around 1 m the copter hovers, goes up a couple of cm, and then lands after some seconds.

I attach a new Youtube video describing this behavior.

Best,

Javier

Youtube video
Log file

Looking at the video and from my experience your irlock is working great.

That slowness at the end i think is precision landing doing its things to land as precise as possible.

Not bad at all.

Corrado

1 Like

@Javiercerna
Yes, @anon67614380 is correct! That behavior is intentionally programmed into the flight control code by the developers.

Regarding rangefinders, we highly recommend the LW20/SF20 units, due to their compatibility with our MarkOne V2.0 beacon.

I hope this is helpful.

Best,
Thomas