Swashplate movement question

I got my Goosky RS4 heli setup and the swashplate moves the way it suppose to corresponding to stick movement.
however, if I tilt the heli on a bench to see how the FC is compensating for the tilt,
the swashplate seems to be moving in the same direction as the fuselage, not the opposite direction of the fuselage. this is true for both roll and pitch direction.
how do I fix this? I tried changing all sorts of the values to no avail.
also, the servos seem to move very slow (except for the collective movement), including rudder servo. and I’m coming from “Rotorflight” experience, where the servos move much faster with the stick movement.
I tried spooling up the main rotor, and the tail holds, which means the rudder servo is doing it’s job, even though it is slow to move when stick input is applied. but obviously the heli is trying to flip itself over real hard, unless I move the collective all the way down.

Hi @David_Jacobs , for roll flip servo slots and try reverse. For pitch servo use reverse. You can do this through servo setup page in Mission Planner (tab for reversing and dropdown menu for changing output) and check it on the go. Once the stabilization movement is correct you can reverse stick inputs from your RC.

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I didn’t even consider to invert the output in the transmitter.
but it is now working correctly, and I was able to hover the heli.

however, I still have the problem of the servos moving slowly.
feels like delayed reaction. when I let go of the stick, the tail still turns for awhile before it stops.
which values need to be adjusted for this problem?

also, any amount of trim in transmitter will disallow arming.
I have to recenter all the trims in my tx before able to arm.
is this normal for Ardupilot ?

for the reference, I’m using Matek F405 WTE with built int ELRS rx, and Radiomaster TX16s with external ELRS module

Welcome to Ardupilot! Have you been following the steps in the wiki for setting up your heli?

I took a quick look at Rotorflight. I suspect that the control laws used are quite a bit different from ardupilot. It appears that rotorflight is designed more for sport flight where as Ardupilot focuses more on autonomous flight but can still be used for sport flight. I suspect you are more interested in flying aerobatics and using the Acro flight mode? I only ask because I would encourage you to do your initial tuning and setup using stabilize flight mode which is a 2D flight mode. Once you have the heli tuned well, then you can proceed in using Acro which is a 3D flight mode.

There is probably a couple of things contributing to this but mostly it is probably due to the default settings of the command model. Arducopter uses a command model which dictates how the aircraft achieves its response. you may refer to this as the feel of the aircraft. Is it quick or slow. This is all user settable. You will have to go through the process of tuning the control system and then setting the command model parameters to your liking.

this is very normal. you should never have to touch the trims on your transmitter. Currently you need to hold your sticks out of center because your heli is not tuned properly. Be sure to go through the set up and tuning. That should fix the issue of having to hold the sticks out of center for a steady hover.

Please post a parameter file so we can take a look at your setup. Also if you haven’t used the wiki to do your setup, please go back through and verify that you have followed the steps. Watch the videos as well. It is important to get the setup right to avoid problems in the future. if you have any questions, don’t hesitate to post them in this forum.

Also, bench testing of servo movements is not really representative of the actual in-flight servo rates. If you want to share the log of your successful hover test then we can review with @bnsgeyer and guide further.

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Hi David,

I saw that you were able to get things worked out with reversing the outputs of your radio, but I’m just curious…is your AHRS_ORIENTATION set properly for the direction your FC is mounted?

For example, if FC is facing backwards from normal, AHRS_ORIENTATION would be set to 4 (rotated 180° in yaw axis).

Do you mean when the FC is compensating? Coming from FBL controllers to FC’s, I was also a little surprised with the small amount of servo movement when doing test leaning.

I’ve noted that, at least with my FC, that the compensation is easier to see if you do more abrupt/aggressive motions with the helicopter (i.e., to see tail compensation easier, move the tail in quick movements from side to side).