When is acro mode coming?

[Patscherpofel]

thanks for all the help, I will test more and maybe should start a new thread about it
I fly expo around 85 ,and correct, this was not helping the gps mode
now truning down GPS P and switch the expo to 0 defiantly has the wanted effect
I have to test it in wind to see if its will hold the position enough like this

one last thought...
correct me if am wrong, but somehow I feel the stick input is treated like an external error that the gps calculation tries to fix the same way like an unwanted external force , like wind for example
what if the stick position would get into the calculation separated or at the very end to avoid this problem?
this way there could be a parameter to ramp the stick input somehow to make movements more related to to stick input and still have it fight wind agressively at the same time?

[LPR]

[Patscherpofel]

thats a good idea! will play around with that

[Mullet]

Ok... to summarize: Quatos with Acro mode would work quite well. Normal PID with Acro would require retuning.

So here's another suggestion. Multiple profiles which can be switched via stick command. This would allow one to have one profile for Quatos, one for PID with normal flight characteristics, and one for PID with Acro mode. Even without Acro this is still useful for one who wants to switch between Quatos or PID.

[chschmid]

AFAIK you can not do acro with PID attitude control.
With Quatos you can (could).

[Max]

Works great with either controller. I actually like the feel of PID a bit more, Quatos has some pretty heavy filtering applied (but I'm playing with that).

I made a new set of params for flying in rate mode and that takes care of the difference from angle mode. So the current D and F terms are used in angle mode and a new P/I/D/F set is used in acro, and each can be tuned separately. The maximums stay the same, they are not a problem.

Different profiles are a good idea though I was thinking something like saving multiple profiles to the SD card and then being able to load specific ones (by setting a param and/or using sticks somehow). You'd have to land anyway to use stick commands, and to go from Quatos to PID you need to restart anyway (as well as for many other params). I'm hoping for rate vs. angle flight mode we can just stick with one set.

Ended up re-writing a lot of the control code so it's taking a bit longer while I dig myself out of this rabbit hole.

-Max

[chschmid]

[Max]

I described previously what I mean by rate vs. angle mode, which is why they're called rate and angle mode. In rate/acro mode you do not control the angle of the craft, therefore the gimbal lock/Euler angle singularity problem does not apply here at all. See above for Bill's answer to the same question.

An 8-bit Arduino can do rate mode, you don' t even need ACC sensors for it. My first quad just used heli tail gyros and elevon mixers. It even sort-of worked... In AQ right now when you command yaw manually you're using "rate mode" with both PID and Quatos... which is why we set the yaw Rate in deg/sec vs. the Scale setting for pitch/roll which scales the RC request to an angle as described in the wiki.

I did also add a manual tilt rate param as well. Definitely need that separate from the yaw rate.

What do you understand "acro mode" to be? All the FC code I've looked at (MWii, etc) defines it as gyros-only mode where you control rate of rotation instead of angle.

-Max

[Max]

Simulators let you do some fun things... I set high scalings on my pitch/roll controls (0.1) and a high Quatos max. tilt rate. You can in fact command something silly like a 360* roll/pitch angle with Quatos, and it does work... sort of. When you release the stick, it flips back the same 360*. Same goes for any maximum angle.

If you kill the motors completely during the roll (throttle off), and still manage to complete the roll, then when you throttle up again it returns to level w/out flipping back. Neat trick for sure, but maybe not something I'd want to try with any real MR I care about.... although I managed a decent success rate in the sim.

So if there was some logical way to detect when to reset (flip) the angle demand, one could theoretically do some 360* acrobatics while in angle-control mode with Quatos. I guess detecting the current angle and doing some clever quaternion rotation if we're flipped on one or both axes... could be interesting for sure.

With angle PIDs it sorta works until you hit the gimbal lock (singularities)... then it's all over.

-Max

[chschmid]

Hey Max
I am eager to see what you are coming up with.
As long as we can fly a loop/flip ....

Cheers
Christof