LIDAR on Quadplane

ArduPlane Plane 3.7
1

Hi there,

Is it possible to use LIDAR during VTOL_LAND? If yes, does it also work when Q_RTL_MODE parameter is set to 1?

Finally, is there a SITL Octo-quad model available?

Detleff.

2

Isn’t there anybody who knows the answers??? Or am I in the wrong forum??

3

Yes, CanberraUAV’s X8 QuadPlanes hvae LIDARs on them, and they are used during VTOL landing.

There is no model for a SITL Octo-QuadPlane; we made to with 5 motors on the sim :slight_smile:

4

Great, thanks for the reply. I was already wondering how they handled the possible altitude differences in take off and landing area.

I couldn’t find any special setting for activating the Lidar (rangefinder) for quadplane operation. Are the standard parameters enough to make it work?

5

We also surveyed the areas around Dalby by driving around and checking what the altitude differences were like. And the 3G reception while we were at it.

https://github.com/ArduPilot/ardupilot/blob/master/ArduPlane/quadplane.cpp#L757 is where you can see the relevant code, including use of the RNGFND_LANDING parameter.

1 Like
6

I have tried to install the Lidar, but it wasn’t really working. Also, they are quite big and heavy, and expensive. Around 200 USD is quite a lot.

My problem is this:

During long flights (mapping flights for example) with my quadplane, I noticed quite some barometer drift. Sometimes nothing, sometimes a lot. On my last flight it was actually 7 meters in the wrong direction. That means, the Pixhawk thought he was still 7 meters up in the air, but already on the ground.

That means, there was never a flare to slow down the descent rate which is set at 5 meters.

Fortunately I set the descent rate not too high, so the landing was still ok, a bit fast, but no damage done.

So my thinking is like this:

If I could use a simple, cheap ultrasonic device to initiate the final landing stage, it should already be ok. Most of them work in the range of 3 to 4 meters, which should be ok for starting the final, slow landing descent and also solve the problem of landing detection.

Do you have any idea if this is possible?