Autotune changing acro values under the hood

This one took me quite some time to find. I used to think autotune was just setting up very “conservative” values resulting in a slow ACRO roll rate after autotune. I tried manually increasing P gains and it wouldn’t help.

I had configured to be 360 deg/s, but after autotune the plane was rolling much slower. I would always end up reverting to the tune before autotune and flying that way. I ended up doing a compare on the complete parameter list and found that three RMAX values were being set that override the ACRO_PITCH_RATE and ACRO_ROLL_RATE. By default the RMAX values are all 0, meaning the two rates above are in effect. Then after autotune they typically end up around 60-75 deg/s. I tried setting them back to 0 and doing another autotune hoping that some flag would be set to not alter the RMAX values but that’s not the case.

Here are the values that autotune sets, which override the acro rates I was trying to achieve:

I believe there should be a way to autotune with the desired ACRO rates, and feel that these conflicting parameters are an artifact of updated code. Does anyone have insight on the history of these parameters and if this should be corrected?

it sets the max rate depending on the aggressiveness you select, 360 deg per sec is above the default for the maximum level of aggressiveness.

You can of course just change them back once the tune is complete.

I understand what it’s doing, but consider a user who goes into the ACRO settings and sets a desired roll rate. They will never see the rate they desire after performing an autotune unless they find these obscure rmax values and set them to 0(documentation says 180 is the max so they must be disabled to get anything “sporty”).

I found out there is already an issue mentioning this parameter:

you can set it above 180, nothing bad will happen. The ranges in the parameter are just guide lines that will apply to most vehicles. (this is not true for all parameters, for some the ranges are important)

The way the autotune uses the desired roll rate is to know whether or not the user has requested a large enough rate to allow tuning. ie you have to achieve 80% of the max roll rate for example for tuneing to be done. (this is equivalent to copters twitches). so you cant tune with a disabled max roll rate

Ah, that explains why it is being set by autotune. Maybe the best answer is just to update the parameter documentation for ACRO stating that the RMAX values will override the ACRO settings so a user knows to go set RMAX higher or off after autotune has been completed.

i have done a PR to make the arco roll rate over ride in acro mode, as in the pram description