New kind of mission item for taxiing

Hi all,

I am trying to add a new item “Taxiing” to the FW mission flight mode.
I’d like to implement a mode that automatically runs on the surface at a certain groundspeed (3-4m/s) along a designated path. At least yaw(wheel) and thrust are expected to be controlled automatically.

In order to implement such a mission item, can you give me some tips on how to proceed, or which part of QGroundControl and PX4 I should look at?
I watched this video on the Flight task and it was very clear, but I feel like I need a little more complex programming to accomplish my goal.

Any advice would be greatly appreciated!