P.S. for anyone else reading this thread, we are now discussing how to improve terrain following, which is handled outside of the EKF.
Do you care to elaborate on this topic on what needs to be “looked” at with terrain following, are there some short comings/outside cases that the community needs to know about?
I know of one issue. When terrain following with a rangefinder in Auto mode, any rangefinder glitches will cause the drone to respond since it’s not using the filtered rangefinder value from the EKF. It doesn’t do this in pilot-controlled modes.
There are some other issues/enhancement requests as well:
But I think the biggest improvement we could make to terrain following is to determine the slope of the terrain below the vehicle (using at least 2 Lidar, a multi-beam lidar or a 3D camera) and then proactively feed this into the altitude controller. This would result in a much faster response.
Some Time before we were testing with the Intel Realsense 3D Camera and we got quite good terrain follow results because one part of the camera looked in front as “Objekt Avoidance” and the other part was looking down for altitude estimation.
And, that System works also fairly reliable over water.
For Pitch and Tilt compensation I put the cam on a gimbal.
One disadvantage was that we had to carry another Computer with.
Unfortunately I don’t know nothing about the software which was running on the computer