Servo movements on bench

[senaka]

Can someone please help to verify from the videos if both the rudder and Swashplate movements corresponding to the stick movements are the same on the bench? Thanks

Spirit GT ver4.0.0
Frsky fbus


Rudder
https://youtube.com/shorts/D9n_-vnj4mQ?feature=shared

Swashplate
https://youtube.com/shorts/Np82SvJpcZk?feature=shared

[davehour]

Hi,

Although I don’t see anything wrong in movements, it would be better if you make the videos showing the Tx sticks as well.

[Mattes61]

Hello senaka,
the one problem you make yourself is that the helicopter is not in the air -
If you do some erratic mini stickdeflections you get some "erratic" behavior that you didn't get in the air - you are on the bench and the some movements overlap and it looks like erratic behaveior on the bench...
To test it really you shoud do not so short erratic deflections in different directions in my opinion - test it with longer constantly inputs and not changing inputs in 0,3-0,5 sec then you will see an constand behavior and in the air it is always other then on the bench do not forget that this is a control loop and if the heli did not react the control loop will do some what you not understand on the bench -

Best regards
Matthias

[davehour]

Hello senaka,
the one problem you make yourself is that the helicopter is not in the air -
If you do some erratic mini stickdeflections you get some "erratic" behavior that you didn't get in the air - you are on the bench and the some movements overlap and it looks like erratic behaveior on the bench...
To test it really you shoud do not so short erratic deflections in different directions in my opinion - test it with longer constantly inputs and not changing inputs in 0,3-0,5 sec then you will see an constand behavior and in the air it is always other then on the bench do not forget that this is a control loop and if the heli did not react the control loop will do some what you not understand on the bench -

Best regards
Matthias

Excellent post!

[senaka]

Agreed, thanks both for the input.

[franz88]

Adc filter is deactivated?
In edge tx nane is adc filter in ethos I don't know what it's called

[senaka]

Adc filter is deactivated?
In edge tx nane is adc filter in ethos I don't know what it's called

adc filtering was enabled, however tried after disabling and the results are the same.

After spending some time on this, I think I kind of know how to reliably reproduce this on my setup. and it had to do with the position of channel 12. Really weird but here it goes after reproducing on two different sets of hardware.

Im based on frSky and using an archer plus 10+ interfaced with the spirit GT (ver 4.0.0)with fbus. on the tx is set to 16channels access protocol.

All servo moments are smooth as expected, but as soon i create a new mix using channel 12 and the position set to around +5% (1525us) via a slider or pot, then the issue starts, no other position recreates the issue, nor any other channel 13, 14, 15, 16 with the same output value of +5%.

I haven't assigned this channel to any function on the spirit. So far i haven't found a reliable way to further isolate the problem say if its something to do with the fbus frames entering the spirit. If i closely see, i can almost view the non linear movement on the pitch channel via the diagnostics page on Spirit software.

I plan to update the firmware of the transmitters rf module, will keep you posted.

[Mattes61]

Hello Senaka,
maybe it is a theme of the deadband ? The deadband in the standard setting is at 10 -
You can change it to 2 and verify if that has an impact -
I don't know if the stickdeadband is only for the two sticks or if that applies also on sliders, potis etc. ...

Nearby I have yesterday installed the new firmware 4.0 for the Spirit GT - I am also flying with FrSky but my receiver is an Archer R8 Pro with redundancy of additional Archer RS -
I have an X18 SE with the newest ETHOS 1.6.3 with updated HF to 3.0.3 TD ISRM file -
For my receivers you must nothing update but for the most others you have to update in conjunction with the new HF-Firmware.
All works as expected - because of the weather I was not able to fly but I think all will be ok !

Best regards
Matthias

[senaka]

Hi Mattes61,

The stick deadband was set to 2.

I have updated to Ethos 1.6.3 and the rx to 3.0.1, unfortunately the issue remains.

For now ill just remove/ not use ch12 in my setup, then all is fine and smooth until i find a way to isolate the issue.

[ZeXx86]

Thank you very much for very interesting finding.

From the FBUS processing point of view, there is no difference between 8 - 16 channels.
For what purpose are you using this channel?