KISS and AUTOQUAD

[afernan]

I´ve worked a lot with KISS and AUTOQUAD trying to get it working together since KISS is a very good ESC, cheap, simple and very performance. But I did´nt get allways a success history, mainly in larger mounts due to hard frequency couplings between frame , control and KISS (it has freewheeling).

I found very difficult to get a reliable configuration robust for frame changes (like weight, gimbal, battery, etc). Tuning is difficult (always using PIDs) but when you succeed, then it´s an awesom copter, with a super precise and robust flight mainly under wind.

There´s a number of post and guides in our wiki were I show diferent mounts. I normally succeded with small mounts (< 700g copters) but with large copters you must have a lot of care with the design.

After a lot of tries and study I could isolate the potential frequency coupling problems by using a very stiff frame (freq > 161 Hz) and the right control parameters tuning (PIDs.)

The video below show the maiden test flight using exactly same frame that I use for QUATOS, ESC32 (flying very well) but now usin PIDs and KISS. It flies very very well. Acc levels are negligibles, very small, below 0.5m/s2 in hovering.

Tunning was not so easy. In general I needed to low a lot many of the Tilt params, including Fterm. Attached the params I´m using. Main changes wrt deffaults:
TRD = 15000, Fterm = 0.125
TAP = 150
TAD = 6000



Enjoy

Angel

[kinderkram]

Yeah, this is the one!

Thx for the parameters, they will surely help with my build after I received the carbon tubes next week (hopefully).

[leopold1]

Impressive!!

[leopold1]

Angel, does it use the same centerplates as your version of the tank quad?

[chschmid]

Hi Angel

Very good values. I have hardly seen so low vibs. Congrats.

Cheers
Christof

[aBUGSworstnightmare]

Great performance! Well done!

[chschmid]

Angel
How did you perform the auto landing and the autostart?
What is you nav speed?
What is the descend rate.

Cheers
Christof

[afernan]

@leopold1, I´m using this center plates from the begining (maybe 2 years ago now!). Always same plates in all my builds. Many peoply are using it also.

@Christof: I´m using all deffault values for NAV. Auto-landing is part of the current code: while in PH simply set the throttle stick a bit below the center and leave it alone: it will land, stop the motors and disarm automatically.

The same for AUTO-Take-off: arm / set PH / and move throttle stick slightly above the center: it will take-off alone and smooth.
In both cases, the position of the Thro stick wrt center will define the descend speed or the take-off speed.

I´m preparing now a version with "pusher" propellers (upside down motors). It has two advantages:
1) much better aerodinamic effitienty (will gain some flight time)
2) and more important: tubulences around arm fully dissapear. These turbulences add noise to the acc signal (not negligible for a cilindrical body). This removal will improve more the control.

Anyway still some room for PID params improvement, for sure.

Angel

[Max]

[afernan]

@Max:
you´re right. Disam will not occur when landing, only motors off. I´ve mixed with the "land" command used in a mission that performs a "disarm" . Anyway, I´ve been using everyday a lot both auto land-takeoff and never had an issue.

Angel