Does VTOL back transition have a height rate control?

[fly_check]

I was looking at the code and saw that there is a pitch setpoint dropping in from a deceleration control. I have observed that the height rate is somewhat close to zero as well. Just wanted to understand if there is a throttle to height rate controller code sitting in the code. If yes, where exactly can I find it?
@JulianOes @sfuhrer can throw some light on this?

[JulianOes]

Can you zoom out and give some context. And maybe a log and the PX4 version you’re using?

[fly_check]

This was observed during VTOL back transition. During Back Transition. In the code, I could see that the pitch setpoint is held zero (standard.cpp).

While running the simulations and even from flight data, I could see that the height rate settles to zero as well. I wanted to know if there is a throttle to height rate controller that maintains height rate zero?

I am working on PX4 V1.15.4 and I wish to customize the VTOL back transition to avoid aggressive pitch occurrences.

Thanks and sorry for not giving a context

[JulianOes]

Ah, so you’re referring to this?

src/modules/vtol_att_control/standard.cpp

[fly_check]

yep, wanted to know if there is something similar for height rate control as well. Because here we can see that it is clearly a controlled parameter.

[JulianOes]

height rate, so in other words z velocity?

[fly_check]

Yeah, during back transition a zero z velocity is observed. Just wanted to know where in the code that is defined.
Thanks

[sfuhrer]

Here you go: PX4-Autopilot/src/modules/flight_mode_manager/tasks/Transition/FlightTaskTransition.cpp at 2106c6ca823995f60a149b646b164adb4fa11e93 · PX4/PX4-Autopilot · GitHub

[fly_check]

Thanks a lot, this helps a lot!!