HereFlow use pointing top for indoor flight

Hardware Multirotors
1

Hi all,

I’d like to use HereFlow for indoor fly, but I’d like to use it pointing to the roof of my indoor place. In the wiki it’s say

The flow sensor should be mounted on the underside of the copter with the camera lens pointing downwards. The side of the sensor with the lens should be towards the front of the vehicle.

So I guess the config is done in the source code, my question is can I use it pointing to the top and not downwards, should I modify source code ? OpticalFlow libraries ?
And I’d like to use another Lidar, so I guess this is ok because we already have RNGFNDX_ORIENT param with 24 for top

2

Yes, you must change the source code and create a “github pull-request” so that the developers can review it and give you feedback.

3

Ok nice I’ll check the source code to understand how it’s work

4

Ok so I don’t know if anyone can help me or guide me just to know if I’ve understand well whant I nedd to change to use hereflow pointing to roof.

For me the only modification to be made is on the Y/Z axis if I returned the HereFlow, that’s right?

So the idea will be to create a new PARAM here (like an AP_Int8) and with this param reversed Y and Z value here in flowRate and bodyRate vector
Am I on the right way? :blush:

5

Just a question because I’m little bit confused about body/ frame axis definition. So for the hereflow here is the axis

Capture d’écran 2022-05-05 à 15.17.59
Capture d’écran 2022-05-05 à 15.17.59868×1398 104 KB

So for me the axis about the Cube is like that
About Aerospace Coordinate Systems - MATLAB & Simulink

is it right ?

So I’m little bit confused about hereflow and the cube axis if I follow the base configuration

The flow sensor should be mounted on the underside of the copter with the camera lens pointing downwards. The side of the sensor with the lens should be towards the front of the vehicle.

The configuration should look like this :

IMG_1002
IMG_10021920×2560 157 KB

if I’m right the coordinate system does not match at all, the coordinates of the hereflow and the cube must be the same, right? Or there is a conversion in the source code ?