Swash movements all correct EXCEPT ONE? RESOLVED!
« on: October 17, 2018, 10:28:48 pm »
Setting up a Trex450 with flybarless head and a CC3D.  GCS and CC3D both at 16.09.
   Progressing slowly through the heli setup routine, swashplate level at zero pitch and mid-throttle.   With CC3D in Manual mode, swashplate reacts properly to all Tx stick movements and does NOT move when heli is tilted in any direction.  OK so far. 
   The problem: In Rate or Attitude mode, the swashplate still moves correctly in response to all Tx stick movements, and tilting the heli side to side works as expected (swashplate moves opposite the tilt) but tilting the heli nose-up causes the swashplate to tilt in the wrong direction (backward, instead of forward, and vice-versa).
   I tried reversing the pitch channel on the configuration/output screen but all that accomplished was to mess up the collective.
   Is there a way to reverse the cc3D-generated swashplate movement without upsetting the Tx-generated movement? 
« Last Edit: October 21, 2018, 05:30:38 am by Bobrcnut »

Re: Swash movements all correct EXCEPT ONE?
« Reply #1 on: October 18, 2018, 01:32:03 am »
Is this a 120 degree or 90 degree setup?

I'm going to make a guess that you have tweaked something to make things right, but didn't know all the places to tweak.

I think you may have a problem like this if you didn't set the control reverse check boxes correctly when running the transmitter wizard.  You then reversed it on the output page, but that didn't fix the stabilization direction.

I suggest you save your settings, erase, and try again as being an easy fix if that is the case.

Or perhaps you have the FC mounted backwards with the arrow pointing rearward which causes more problems, some of which you have tried to fix but should be fixed by changes to Attitude->Settings->RotateVirtual
If that is the case you will either need to undo the fixes or start over, followed by a change to RotateVirtual as the first thing done after the wizard.
https://librepilot.atlassian.net/wiki/spaces/LPDOC/pages/5669054/Revo+Attitude+Configuration?focusedCommentId=98653228#RevoAttitudeConfiguration-VirtualAttituderotation

Re: Swash movements all correct EXCEPT ONE?
« Reply #2 on: October 18, 2018, 02:56:24 am »
Cliff, thanks for the clues.

   Tx is set to 90 degree, single servo swash.  Configuration/Vehicle page is set to 3-servo 120 degree swash. CC3D is mounted horizontally with up side up and arrow pointing left, with yaw orientation set to 90.  The PFD vehicle icon and the artificial horizon both react correctly to physical movements of the heli frame.

   Another clue:  on the Config/Input screen, moving the Tx throrrle stick up or down causes the Throttle and Collective sliders to move in opposite directions, but the swash moves up and down correctly.

   I think you're right about my making setup changes out of sequence or in the wrong place... further testing shows that changing any one parameter yields different (but always wrong) results.  I'm gonna start over from scratch, because I think I'm still confused about the relative effects of reversing a channel (1) inside the Tx, (2) on the Config/Input page, or (3) on the Config/Output page.

I've also determined that the Wiki 'How to' about ESC calibration does not work when using Castle Creations ESCs, so I'm gonna put together an addendum for LP's review.  The problem is because, with Castle's ESCs, you don't calibrate the ESC to the Tx throttle signal... you adjust the Tx throttle signal to match the ESC.

   More later, and again, thanks.

karla

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Re: Swash movements all correct EXCEPT ONE?
« Reply #3 on: October 18, 2018, 03:03:39 am »
   I tried reversing the pitch channel on the configuration/output screen but all that accomplished was to mess up the collective.

On Configuration - Input - Remote control Input, try change the Pitch channel (check the Reversed box or uncheck it, depending what you have now).
To get all the swash plate directions working correctly you may need to get a combination of reversed channels both in the Output and Input pages.

Re: Swash movements all correct EXCEPT ONE?
« Reply #4 on: October 19, 2018, 05:08:09 pm »
   Karla, thanks for the input here.  I'm sure I'll get it right, either by logical thought, or by trial and error.

   My setup is a bit more complicated by the fact that I have 4 different ways to reverse each servo's movement...
-- Via Transmitter's normal/reverse setting
-- Via Config/Input
-- Via Config/Output
-- Via offline servo programming with Hyperion Emeter II
...Which means 16 possible combinations for each of the 3 swashplate servos.

   It may take all weekend, but I'll get it working one way or another.. and post the results here.

Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #5 on: October 21, 2018, 06:14:03 am »
   Well, I finally figured out what was going on here.  It was 'sort of' a user error, but I'm not taking ALL the blame.

   After spending hours trying different combinations of Tx channel reversing, Config/Input reversing, and Config/Output reversing, each attempt only made things worse... so I gave up for a while.  A bit later, I went all the way back to 'basic heli setup 101' and built an Excel spreadsheet showing which way each servo should move for a given Tx stick movement based on the mechanical linkages.  Then, I duplicated the setup with a separate Rx and 4 spare, unmounted servos, and tested each servo one at a time using only the throttle channel.  All 4 rotated CCW in response to increasing throttle.  I repeated the test using the servos mounted in an old Hurricane 425 heli (non-LibrePilot)... and again, all servos turned CCW when throttle was increased.

I then used the same method to test the 4 servos in the CC3D 450, and lo and behold, one of these 4 rotated in the wrong direction.  The final fix was to simply re-program that servo offline using the appropriate software to reverse that servo's rotation internally so that the Tx (and LP) would be unaware of the change.

   After a few more setting changes to the CC3D setup channel reversing, it finally worked as desired.   Swash moves correctly for all Tx stick movements, AND tilting the heli frame (in self-leveling mode) causes the CC3D to move the swash properly in the opposite direction.

   Apparently, heli designers assume that all servos will rotate the same direction in response to the same signal, and design their linkages accordingly... but if any one servo does NOT, it can create a situation that simply cannot be overcome through channel or servo reversing options because of the fact that any one cyclic servo has to respond to signal changes from multiple channels.

   Sorry for such a long post here..




karla

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Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #6 on: October 21, 2018, 06:26:25 am »
Wow, well done.

Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #7 on: October 21, 2018, 06:35:03 am »
It should work if you:
- run the transmitter wizard (built into normal setup) which gets the sticks and input correct
- from now on, don't touch reversing in the transmitter or on the Input page
- a strong point can be made that you should not touch anything in the transmitter at all, not trims, not subtrims, not endpoints, not dual rates...
- use any stabilization setting (including Manual)
- reverse individual servos as needed, using any output method (including Output page reversing, manual linkage reversing, or reprogramming servos)

If you are really interested in this, you could try proving it by setting that servo back the way it was and following the above procedure.  You should wind up with everything in the correct direction.  :)

Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #8 on: October 22, 2018, 04:09:03 am »
   Cliff, I have no doubt at all that the procedure you recommended above will work fine, but I am unable to use it.

   First:  I've mostly been using the Heli Setup guides posted here by JWgera and Jerry Cronus.  Neither of them make any reference to using the Tx Setup Wizard.  Is using the Tx Setup Wizard mandatory?  And, if so, doesn't that mean the Tx initial setup must include a Throttle Hold function, as requested within the Tx Setup Wizard?  If so, that disagrees with the setup methods referenced above and the LP Wiki.

   The reason I ask is because the Tx Setup Wizard does not work for me.

I first set up my Tx (Hitec Aurora 9) exactly as specified in the above setup guides.. no channels reversed, no Expo or dual rates set, no Throttle Hold, Throttle Cut, or Idle Up settings activated, straight throttle/pitch curves (0-100 linear), a Flight mode switch assigned to channel 5, aircraft type = Heli, Swash type = 90 degree single servo, and all endpoints set to 0-100 with one exception:  my throttle channel endpoints are set to 91% high and 83% low.  This is the result of calibrating the ESC, done offline before firing up the GCS.  (As previously noted here, the Wiki-recommended ESC calibration procedure will not work for Castle ESCs.).  However, I don't believe this is relevant because doing  the ESC calibration after setup is completed, makes no difference.

   Next, I set up the Config/Vehicle Basic Settings as recommended.  No problems here.

  My problem occurs after starting up the Tx Setup Wizard.  It locks up part way through the process:
-- Wizard asks for Tx type. I specify 'Heli'.
-- Wizard asks for Tx Mode.  I specify Mode 2.
-- Wizard says to enable Throttle Hold and move the Tx Collective stick.  I have no Throttle Hold set up, so I just move the throttle/collective stick.  The animated Tx graphic stops briefly, then asks me to disable Throttle Hold and move the throttle stick.  I have no Throttle Hold activated, so I just move the throttle/collective stick.
-- The green bar shows PWM activity on Channel 6, but nothing happens.  The Tx graphc continues to show a moving throttle stick, and the Next button remains disabled.  My only choice is to press Cancel.  The same thing occurs regardless of the type of receiver... PWM, PCM, or SBus.

   Consequently, I instead use the 'Manual Calibration' button to assign input channel numbers and types, which all work out fine... when completed and saved, all channel sliders react to the stick movements properly, and the throttle channel shows slightly reduced Max. and Min. values as expected.

   What have I missed, or misunderstood?

Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #9 on: October 22, 2018, 04:48:49 am »
Sorry that I haven't used the heli setup wizard.  My comment was that generally if you don't mess with input after Tx wizard, that it should be correct.  I suspect that if you had a working throttle hold then it might work for you.  The reason it needs throttle hold there is so that the throttle stick only moves the collective channel.  That way it can see which channel it is.  Without that, it is confused.

Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #10 on: October 22, 2018, 06:45:02 am »
   Cliff, thanks for the clarification.

   I suspect that what happens is this:  without throttle hold activated, the Tx Setup wizard sees changing input from both channel 3 (throttle) AND channel 6 (collective) at the same time.  I'll research this further.. but for now, I at least have a  properly working setup.

utoedter

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Re: Swash movements all correct EXCEPT ONE? RESOLVED!
« Reply #11 on: October 22, 2018, 09:00:29 pm »
   Cliff, thanks for the clarification.

   I suspect that what happens is this:  without throttle hold activated, the Tx Setup wizard sees changing input from both channel 3 (throttle) AND channel 6 (collective) at the same time.  I'll research this further.. but for now, I at least have a  properly working setup.

Maybe the wiki helps.

https://librepilot.atlassian.net/wiki/spaces/LPDOC/pages/5669259/Helicopter