weijay

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Re: limited collective pitch
« Reply #15 on: May 04, 2016, 05:06:49 am »
Thank you very much for you and your friend's help.

This morning I ran further test.
Online I found indications of HXT900 servos were prone for signal interference and could result in jittering. So I tried to use 3 genuine hitec servos. They behaved the same.

I went back to the GSC, and found that the servo jittering position shifts as I change the neutral position on the control input.

By changing the end points of the channel in the TX, does not improve on the jittering.


Summery:
The jittering occurs with all three servos of the collectives. They all jitter in the same direction, and occur constantly at the same position of the stick input. The jittering spot on the TX control stick shifts when I change the neutral position of the GSC control input.


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weijay

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Re: limited collective pitch
« Reply #16 on: May 04, 2016, 06:09:43 am »
Hi Dave,
Thank you for your time, I  managed to fix the jittering problem.

That is go to system/settings/Mixersettings/ curve2source and change it from throttle to collective.

Thank you very much for putting the time to help me. Cheers


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daveapplemotors

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Re: limited collective pitch
« Reply #17 on: May 05, 2016, 01:06:21 am »
Dooh! I should have seen that. I am glad you did and I hope you are flying soon.

Happy Landings!

weijay

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Re: limited collective pitch
« Reply #18 on: May 05, 2016, 01:34:18 am »
Thank you Dave. May be another quick question.

How to I change the limits of the true collective movements.

That is I could have full collective movement in the swash plate setup wizard, however I can only do half of that with my TX stick control. If you can give me a hand in this will be great. Thank you again for the trouble. Cheers

Wei


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daveapplemotors

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Re: limited collective pitch
« Reply #19 on: May 05, 2016, 09:11:14 pm »
Sorry I am so long to get back to you, Wei.

I found that problem, too.

You can raise the pitch *edit [AND ROLL] from 50% to something larger in Configuration / Vehicle 
OR you can change pitch limits in your TX for more collective (Spektrum can go 125%).

But, I just use System / Actuator Settings / Channel Neutral, Minimum and Maximum for leveling and getting the total collective right. I spend a lot of time here watching the swash go smoothly from bottom to middle to top and making small adjustments without running the motor. I get positive and negative pitch equal. I fold the blades together and measure between blade tips. 100 mm gets about 13 1/2 degrees of pitch with my blades.

be well,   
« Last Edit: May 06, 2016, 12:52:00 pm by daveapplemotors »
Happy Landings!

limited collective pitch
« Reply #20 on: December 06, 2016, 10:10:50 am »
Hallo,

You wrote in : How to I change the limits of the true collective movements.

That is I could have full collective movement in the swash plate setup wizard, however I can only do half of that with my TX stick control. If you can give me a hand in this will be great. Thank you again for the trouble. Cheers

I have the same problem in the setup with Librepilot and i don't know how to increase the movement of the swash plate for roll/pitch.
With a other heli i used openpilot and I could increase movement by moving the 'rate' slide bar, but in Librepilot this doesn't work.

Please, has anyone an solution for me?

Thank you
« Last Edit: December 08, 2016, 09:09:25 am by kleijntje »

daveapplemotors

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Re: limited collective pitch
« Reply #21 on: December 09, 2016, 01:49:30 pm »
In "configuration / vehicle / basic settings" try raising the "collective"  and / or "pitch" and "roll".
After doing this do a 'Jerry save' (where you save as 3 servos 140 degrees and save immediately again 3 servos 120 degrees).
I just did that with one of mine in LP and the swash moved much more...

But because I don't like to use the swash leveling routine I do it differently: 

I leave my "collective" at 50% and make adjustments to the "system / settings / actuator settings / channelmax" and "channelmin" to get the total collective that I want. I spend a lot of time adjusting those settings and "channelneutral" until I am very happy with the way the swash moves up and down. Look for smooth level swash movement from top to bottom and also total (equal) pitch at both extremes. 

Then I see if it hovers. If it goes forward when I want a hover I lower channelneutral, channelmax and channelmin on the rear servo by the same amount.   

Then back on the bench I spend more time verifying that the swash moves smoothly to its limits. Test hover again and adjust until it hovers handsfree. 

Spend time on this and you will like the results. Be careful not to go past LVC on the bench. I ruined a Lipo doing this once!   

good luck,
Dave
Happy Landings!

Re: limited collective pitch
« Reply #22 on: December 09, 2016, 02:11:05 pm »
Thanks, I will try it this weekend.

limited collective pitch
« Reply #23 on: December 09, 2016, 05:30:36 pm »
Thank you Dave!

The 'Jerry Save' was the golden tip.

The swash is moving great, I will try flying tomorrow.

Thanks again

utoedter

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Re: limited collective pitch
« Reply #24 on: December 11, 2016, 10:17:36 pm »
Hi Guys,
I have a problem with the collective pitch of my HK450 not going to full range. Collective pitch only at +/- 5 deg. I have tried looking through the GSC, put i could not find anything that was controlling the Min /Max of the collective pitch. So could you guys help me out with this please.

both input and output configuration of controls were Min/Max :1200/1800.

on the swashplate leveling (under vehicles), i was able to get +/- 12 deg. But when I control the helicopter with the TX (Turnigy T9X) i can only get the reduced +/-5 deg collective pitch control.
 

openpilot gsc is version 14.

Thank you in advance for your help.

Wei

Hi Wei,

Well there is a logical explanation for that. Collective and Swashplate movement are mixed together, each by 50 percent. So if you set the swashplate range to -12 ... +12 degree, your maximum collective pitch will be in the range from -6 ... +6 degree. You can change the mixing by changing the ratio, but if you increase the collective part, you will reduce the swash part. If you set the swashplate movement to -20 ... +20 degree range,  you get a effective collective movement from -10 ... +10 degree plus the extra swashplate moves.  It took a while for me to understand it, but since ive changed it, it works great.

Happy flying
Udo