Post by: weijay on April 21, 2016, 04:23:28 am
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
Post by: daveapplemotors on April 21, 2016, 12:57:25 pm
Did you do "Manual Calibration" with defaults in your TX?
Post by: hwh on April 21, 2016, 04:30:54 pm
...openpilot gsc is version 14...
OpenPilot release 14 is ancient, why are you using that old a software?
Post by: weijay on April 28, 2016, 05:49:03 pm
Thank you very much for the reply.
Sorry for the delay response to your suggestions, as I don't always get the luxury of working on my RC planes, due to a young family.
I was using version 14, because there was some issues with my setup due to version 15, (indicated by one of the threads in the forum), but can't remember exactly what now.
Nevertheless, I have changed the GCS to version 15 and tried to setup my helicopter from scratch.
Initially it was pretty good. I was able to setup 3 modes on channel 5, and managed to get my swash plates leveled, and setup both mechanically and digitally for my collectives to do +/- 12 deg. However after I start making adjustments to the stabilization setting, my collectives became not moving much, may be just 1or 2 degrees. I tried to rest all the setting with the default button, but that didn't fix it either. My stabilization mode was actually on manual for both pitch and roll, yaw is controlled by the automation, and throttle is also on manual. Could you guys give me a clue what had went wrong please. thank you very much.
Post by: daveapplemotors on April 28, 2016, 08:47:55 pm
I hope all in your family are healthy. And I hope you can share RC with someone.
You are doing great. You have servos moving and swash level--that is fantastic. You are winning.
In Configuration \ Stabilization \ Advanced \ Rate Mode Response -- (near top of page)
Try "RATE = 540 manual mode" for Roll, Pitch & Yaw and you will see some more servo movement. I always set the Max Rate Limit to be at least 570 so that the helicopter can add it's own corrections. The default, 220, is too low--even for quads. The servos don't need to move much to roll a helicopter only 220 degrees / second. It it hard to see.
I believe stock Blade mcpx and ncpx are set to 540 degrees / second at the factory. You can set it to roll / pivot / pitch faster OR slower by using endpoint or D/R settings in your TX.
With 3 flight modes you set each bank different PIDs and compare mid flight. I make Settings Bank 1 mild (proven, no oscillations) and easy to switch too. Settings Bank 2 is a little quicker (larger P, I) and settings Bank 3 is a little larger still. If it does not oscillate in Bank 3 then land your heli, connect to computer and make Bank 1==Bank 3, make Bank 2 a little larger, make Bank 3 a little larger. Test and repeat until you see oscillations on Bank 3 and not on Bank 1. Do this for each axis: Roll, Pitch, and Yaw.
Land the heli to change flight modes at first but when it flies better you can switch in mid air. I do all my tuning in Rate, Rate, AxisLock. After you have it tuned up then use the 3 flight modes to experiment with Rattitude, Attitude, Acro+,Vbar, etc.
Attached is a very stable but also quick handling UAV for an HK250GT with Tarot head. When work and weather break I will do aerobatic and 3D testing. And maybe record a good video.
Post by: weijay on April 30, 2016, 05:44:09 pm
Thank you very much for the detailed response and suggestions.
I fixed my collective problem by changing the "swashplate configuration" from 120 to 140 and then back again. So this seems to be due to a software bug. I initially tried changing RATE to 540, but it didn't work.
I also fixed the little movement of the roll and pitch. This was done via the pitch slide bar setting on the vehicle page/Helicopter.
However "Now I have a NEW problem"
My collective servos (all 3 of them) make sudden up and down movements (like twitches) when i movement my collective joystick movements of the TX. Before, I can fix it by setting "Neutral position" value of the collective to the same value as "Min" in input settings, however this no longer works me. Please give suggestions. Thank you very much in advance. Cheers
Wei
Post by: daveapplemotors on April 30, 2016, 10:33:02 pm
You are welcome. I hope you get it flying well soon.
Yes the 140 save and then 120 save has been the work around for that bug for over a year now.
Keep the rates at 540 for flying later.
Attach your current UAV so maybe we can have a go at your new problem.
be well,
Dave
Post by: weijay on April 30, 2016, 11:54:55 pm
My Transmitter is T9X using ER9X firmware.
Receiver is hobbyking 6 channel using PPM connection with the CC3D control box.
Servo is HKSCM9 digital servo for collective, and turnigy DS480 digital servo for tail servo. The tail servo works well.
ESC: hobbyking 40A blue SBEC.
Thank you
Post by: daveapplemotors on May 01, 2016, 04:39:13 am
From your UAV:
<field name="ChannelMin" values="985,987,990,986,985,985,0,0,0,0"/>
<field name="ChannelNeutral" values="1200,1494,1494,1491,1491,985,0,0,0,0"/>
<field name="ChannelMax" values="1993,1997,1996,1997,1997,1994,0,0,0,0"/>
<field name="ResponseTime" values="0,0,0,0,0,0,0,0"/>
<field name="ChannelGroups" values="PPM,PPM,PPM,PPM,PPM,PPM,None,None,None,None"/>
<field name="ChannelNumber" values="6,4,2,1,5,3,0,0,0,0"/>
Correct me if I am wrong but isn't channel 6 collective? And the first values are for channel 6, yes? If I am right about channel 6 being collective then the neutral value is much higher than the minimum. 985-min 1200- neutral. I see that the sixth set of numbers--corresponding to Channel #3-- have the neutral close to the minimum.
Post by: weijay on May 01, 2016, 04:55:45 am
Ch1:yaw
Ch2: pitch
Ch3: Collective
Ch4: roll
Ch5: flight mode
Ch6: throttle:
If this may potentially give problems then I can easily change them.
Wei
Post by: daveapplemotors on May 01, 2016, 01:13:51 pm
I do not see any problems with the gs 15a.UAV file. Yet. I will look more.
Did you do "manual calibration" on your TX with defaults set in the TX using no D/R or expo and with default throttle and pitch curve settings?
Post by: weijay on May 01, 2016, 01:53:38 pm
Could it be a HK receiver thing? I couldn't do pwm connection with the turnigy stock receiver though.
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Post by: daveapplemotors on May 01, 2016, 01:59:35 pm
s
I don't know what is causing your jitters. I won't eliminate anything yet. It could be receiver but I don't know.
I have seen jumpy servos due to my own bad wiring. A stray strand or wire from a servo wire that I had shortened caused me trouble once.
Post by: weijay on May 03, 2016, 06:15:16 pm
I tried to setup a new connection using my second cc3d board. This board was bight from hobby king, and the other board was purchased from a different source. They are different in colour, but they we are now uploaded with the same firmware: ver. 15 .
I am now using a different type of servo: the HXT900.
A different ESC. I am now using the turnigy stock 9x receiver, instead of the HK6 channel receiver, and it is running on PWM, in stead of PPM.
I am using same radio with the same settings. The battery pack is the same.
HOW EVER, INTERESTINGLY I was able the reproduce the same collective twitch as the previous setup.
Do you have any suggestions? Thank you.
Wei
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Post by: daveapplemotors on May 03, 2016, 10:10:33 pm
I must confess I have not studied your UAV any more, yet. I have been busy. I will this evening.
Have you tried putting collective neutral slightly above minimum?
And throttle neutral slightly above not equal?
My friend Karla, who is in Beijing, is here now. And maybe he can help. He is smart.
Post by: weijay on May 04, 2016, 05:06:49 am
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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Post by: weijay on May 04, 2016, 06:09:43 am
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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Post by: daveapplemotors on May 05, 2016, 01:06:21 am
Post by: weijay on May 05, 2016, 01:34:18 am
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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Post by: daveapplemotors on May 05, 2016, 09:11:14 pm
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,
Post by: kleijntje on December 06, 2016, 10:10:50 am
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
Post by: daveapplemotors on December 09, 2016, 01:49:30 pm
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
Post by: kleijntje on December 09, 2016, 02:11:05 pm
Post by: kleijntje on December 09, 2016, 05:30:36 pm
The 'Jerry Save' was the golden tip.
The swash is moving great, I will try flying tomorrow.
Thanks again
Post by: utoedter 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