New gimbal support - ROI mission fails to yaw copter to maintain camera azimuth

About two years ago I tested an Alexmos gimbal I built with a short mission with several ROI points. Even though this was a three axis gimbal, only the pitch was controlled to keep the ROI centered in the camera. The camera’s azimuth was maintained with the copter’s yaw.

Here’s the mission:

And here’s the video showing that the mission was successful:

I’ve recently installed a SiYI A8 Mini camera/gimbal - and I repeated the same mission to verify that it also worked properly. And I’m now using the new gimbal support in Copter 4.3.

In this new test, the copter did not YAW to maintain camera azimuth.

Instead, the gimbal yaw was commanded to turn the camera toward the ROI - which was, at points, an angle that exceeded the yaw capability of the gimbal. Here’s a video from this mission:

I’m guessing that this is the result of parameter changes - Copter 4.3 has these parameters that did not exist previously.

These angle parameters for MNT1 are new with the new gimbal support - and I could not find their counter part in the earlier version of Copter.

My best guess is that if I set MNT1_YAW_MAX=0 and MNT1_YAW_MIN=0 that autopilot won’t yaw the gimbal for the ROI - and yaw the copter as before.

These new parameters aren’t in the ArduPilot parameter list wiki yet.

In case anyone wants to dig in deeper, here are the BIN files from the original and the new ROI mission.

Original ROI test mission:

New ROI test mission using Copter 4.3 and SIYI A8:

Thank you

as info - tagging: @rmackay9

If you configure the gimbal as “roll-pitch only” (no yaw) then the copter frame will yaw, just like your old version did.

Yes - thanks. I discovered this two days ago on another ROI test flight. I set MNT1_YAW_MIN=0 and MNT1_YAW_MAX=0 and as I guessed in the comment above, that resolved the issue. Thanks for confirming that this wasn’t a fluke!

I don’t know how much of the changes are due to the new SIYI gimbal driver, or how much is due to overall changes to ArduPilot gimbal support. In my previous work with an AlexMos using MavLink, these parameters didn’t exist - and I can’t find any that appear to correspond it it. The copter simply would yaw to face the ROI.

It doesn’t matter at the moment - but if I use my AlexMos gear again, I’ll have to sort it out.

One odd thing - on the landing phase of the RTL, the copter still faced the ROI, but the gimbal turned 90 degrees left. Sort of odd about that.

Here’s a link to the video feed for that flight: SIYI A8 Mini - Ardupilot ROI Tracking Test - YouTube

You can see the gimbal yaw to the left at about the 3:10 mark into the video.