No PX4 Autotune

Barry_Bolton · September 3, 2020, 9:34am

Why does PX4 not have an Autotune function?

jimdgit · September 3, 2020, 3:49pm

Read this:

Barry_Bolton · September 4, 2020, 9:27am

It does not seem that there is a definitive reason or am I reading that wrong.

jimdgit · September 11, 2020, 2:22pm

My take was they did not feel safe doing this.

ticotico · January 19, 2022, 9:01pm

This is now available, see: Auto-tuning | PX4 User Guide
The following PR has been merged recently:

github.com/PX4/PX4-Autopilot

Auto-tuning of angular rates and attitude controllers (MC version)

PX4:master ← PX4:pr-autotune

opened 01:58PM - 29 Sep 21 UTC

bresch

+2415 -32

**Describe problem solved by this pull request** Trial and error manual tuning …requires good piloting skills and tuning experience. The new module`mc_autotune_attitude_control` introduced in this PR is an attempt to address these issues by automating this tuning process. More than this, the result of the system identification algorithm included in this module will be helpful to the control systems engineer to obtain a simple discrete-time model of the system that can be later used for offline controller design of more sophisticated controllers. **Describe your solution** The auto-tuning introduced in this PR is based on indirect (online closed-loop system identification + controller design) adaptive control theory. Running at relatively high speed in real time on a microcontroller, only recursive filters and estimators have been used. For the same reason, the PID designer (based on General Minimum Variance Control) uses a pre-computed closed-form solution to obtain the result of the optimization problem. ![DeepinScreenshot_select-area_20210905105049](https://user-images.githubusercontent.com/14822839/135276353-8fddb106-a61d-423d-97fa-177a9aabc618.png) For more details, see: [MathieuBresciani_Controllers_auto-tuning_for_multirotors_and_fixed-wing_vehicles.pdf](https://github.com/PX4/PX4-Autopilot/files/7252179/MathieuBresciani_Controllers_auto-tuning_for_multirotors_and_fixed-wing_vehicles.pdf) and the recorded presentation (PX4 Dev Summit 2021): https://www.youtube.com/watch?v=Yzhjlo5FnCU&t=2s&ab_channel=PX4Autopilot-OpenSourceFlightControl. **How to use it?** IMPORTANT: moving the roll/pitch stick of the remote during identification will immediately abort the process. It can be started again using the `MC_AT_START` parameter. It will soon be a single click on a button in the "Tuning" tab of QGC (but it isn't upsreamed at the moment) but for now, it can be triggered manually via the parameter `MC_AT_START` (set to 1, it'll automatically go back to 0 when done). For the rest, follow the documentation in the Skynode manual: https://docs.auterion.com/skynode/advanced-configuration/controllers-auto-tuning **Test data / coverage** SITL jMavSim on this branch: https://logs.px4.io/plot_app?log=d305531b-5462-4b1c-949f-7f89c2beefab Result in `autotune_attitude_control_status.msg` From top to bottom: - current state of the state machine - value of the estimated coefficients (discrete-time transfer function) - signal injected to the input of the rate controller (for system identification) - PID gain generated using the current model and desired meta-parameters ![DeepinScreenshot_select-area_20210929151049](https://user-images.githubusercontent.com/14822839/135275612-dc17414e-1166-42b4-91b9-1a9ee21838fa.png) Replayed on offline Python tool (soon available): ![DeepinScreenshot_urxvt_20210929151343](https://user-images.githubusercontent.com/14822839/135275768-b72185d3-ff77-470f-94b8-fe01612dd6a7.png) Test on a X500 (same algorithm but different branch): https://logs.px4.io/plot_app?log=7a2a60fd-dfba-4356-b92b-5dfd687bd579 TODO: - [x] add module to all targets - [x] find a way to send back the current status to QGC through mavlink (@dagar we used to have a `progress` field in the ACK message but it's apparently not there anymore)