Odd servo behaviour

[twoleftthumbs]

Guy's iv'e just updated to the ver2 firmware and whilst checking the machine over (trex 700 nitro DSX12)on the bench iv'e noticed the following.

my swash is spot on at zero pitch and through the positive pitch range but when i lower the pitch past the zero point into negative my elevator servo has more travel so the swash tips toward the right rear (looking at the nose) ..so if i try and fly it'd start already dipped and level itself by zero pitch but if i try any negative pitch moves it'd tip the swash.
The old version of the firmware had the endpoint leveler that i could have used !!!

Iv'e tried changing the servos over with no change so it's not the servo itself
iv'e started afresh with a new model memory/rebind no change
travel adjust doesn't seem to have any affect so i can't raise that channels end point to match the others.

Any ideas guy's ...thanks

[helipainter]

did you set the subtrims till you see 1500 in the pulse width window at neutral? I never looked at the final release notes, but the beta one we were using needed them all sub trimed to 1500. On my 11x it was stock around 1511.

Sounds like the swash is decaying to your neutral stick position? just a guess

[MarshallB]

Use no sub-trims in the radio!

[helipainter]

This was in the release notes with the firmware they emailed.

"2.) Level the swashplate- For the pirouette leveling it is very important to level the swashplate during setup. With collective IPW at 1500 make sure the swashplate is completely level and the blades are at zero degrees. Check that all mixing arms are level and that the blades pitch gauge at zero degrees. It is best to check the pitch first with the blade in line with the Nose of the heli. Then turn 90 degrees and check from the side, then another 90 degrees and check from the tail, then 90 again and check from the other side. So you are checking that the swashplate is level and at zero. With the flybarless the easiest way to pitch gauge it is to add a flat plate to the top of the head block to line up the pitch gauge against."


my radio did not come standard to sit neutral at 1500,,, is there another way to get the pulse width changed?

[MarshallB]

Is this JR or Futaba? JR is around 1500 plus or minus and 1530 for Futaba.. In most cases it won't be perfect but you need to use 1500 or 1530 on the TG to determine center and let it rule. If it is way off then there is sub-trim or something up in the radio. Make your mechanical adjustments from there off that point such as level swash, etc. In other words, you may be physically at zero on the collective stick but say 1522 on the TG. Move the stick till the TG says 1500 or 1530 for Futaba and the stick may be off a tiny bit. That's the way I set mine up.

[helipainter]

i only used sub trim to make it 1500 dead even. it came around 1511 to 1513. When i first uploaded v2 and hadn't set it up the swash was falling like the OP mentioned. When i set it up with my pulse width sitting on 1500 on the nose, things got different

It is a JR 11x with the latest firmware

[MarshallB]

First off we don't use subtrim to get the numbers. They won't always be perfect but reasonably close. If it is spektrum it may be worth rebinding the receivers. I've not seen the elevator servo behavior you describe.

[ncarbon]

I had mine dead on as well on fc11_i. Loaded fc11_o and noticed the swash issue at low stick as well. I used the reset to defaults button, and set things again, no more issue.


FWIW


Ned

[MarshallB]

Most likely there was some prior setting that the firmware didn't like..Reset to defaults should set the defaults back to those for that version of the firmware..

[helipainter]

I'm not arguing, i'm trying to understand the directions with your help, if you will. What does the last line mean?

"6.)Before flying each of the setup flights make sure the gyros are not drifting and the transmitter pots are not causing drift issues. You can check this by either looking in the interface on the bottom left corner of general settings (Ail Ctrl and Elev) or by going to the input pulse menu in the +menus and reading the outputs .
“+ menu”/Input Pulse Width/Elv Control T 0 G 0
“+ menu”/Input Pulse Width/Ail Control T 0 G 0,
Check for drift after initializing the radio. They should both read Zero. T- is the transmitter and G- is the gyro. If G is not reading zero (make sure the machine is sitting solid on flat ground to not affect this) then reinitialize the total G to reset it. If T is not zero then check your radio for any pot issues Most radios, even brand new ones have T off in the +- 4 range, but zero is ideal."


Is that the 1511 equating to +-4? How do you suggest getting that to zero if it's "ideal"? or is this a luck of the draw?

So according to you guys, reset a new model, reset the totalG then reset the limits? Let the pulse width lay where it falls?

[MarshallB]

That section is telling you how close the gimbals are resting to center! Mine will vary from 0-4! That's ok! If it is way off you may have issues with those controls! Also make sure the model is still when it is turned on as well!

If you get it in the ballpark go with it, it'll probably be fine. You just don't want -25 or +33 or something way off! That might be indicating something going on with the gyro's.

I really didn't think we were arguing!! :) Just trying to get it figured out!!

[twoleftthumbs]

Many thanks for all the input guy's .. special thanks must go out to ncarbon i reset the unit and bingo all is as it should be

my cyclic ipw's are all in the 1509 -1514 range so do i leave those as they are ?

thanks again for all your help

[Gator1]

I have been thinking about doing the update but am concerned about my old settings that have been working well.
Any suggestions about what to do after doing the update? Will my original setting still work only better ?

Any help would be appreciated.

Mike G

[ncarbon]

I have commented and asked about resets, it seems to be a good idea. I have found several items that seemed off, and a reset to defaults fixed the issue. At least that has been my experience.



Ned

[MarshallB]

What I found when testing the beta's was I would start from the beginning when upgrading to those. I would not reset things like servo direction but I would for sure make sure everything worked correctly on the bench. If I were using different stop values and such I would reset those to defaults. The reason is because the way the new firmware flies now is not the same as before and may not even require those changes you have in your current setup. This was a fairly drastic upgrade in the way it is setup and the way it performs. It is way better than the initial release even though I really had no big issues with it either. I always start with new default values after upgrading to new firmware as I want to know how it flies out of the box so to speak. Then make changes from there. I don't want any prior tweaks on the new firmware.

On the last firmware upgrade other than FC gain at around 60ish, I'm running defaults.. If you go by the Total-G detailed instructions it should work great. Curtis is very thorough in what he says.

[Sky Dancer]

my cyclic ipw's are all in the 1509 -1514 range so do i leave those as they are ?


Yep, in that range, leave your cyclic IPW's as they are.... The Total G initializes on your particular cyclic IPW's and considers that neutral. It might only be of concern if your IPW's were much higher indicating something is off in your TX.

The menu selection that shows TX and Gyro drift since initialization is more important but not serious unless you have quite large numbers there <20.
“+ menu”/Input Pulse Width/Elv Control T 0 G 0 (T=TX / G=Gyro)
“+ menu”/Input Pulse Width/Ail Control T 0 G 0

Even new TX's can show as much as 10-15 units off due to the quality of the pots. 10-15 units could cause a little drifting but is still easily flyable. Usually we just give some control anyway based on what we see in the air.

Don C :YeaBaby:

[MarshallB]

Thanks for bringing that up Don, I forgot to answer that question!! LOL! I'm getting too old I guess!! :lol:

[Sky Dancer]

Hi Marshall, I figure if we put our heads together, between the two of us, we can probably get a question answered. LOL!

Don C :rolling

[MarshallB]

LOL!, yep, or at least one fully functioning brain!! :lolol

[twoleftthumbs]

Thats great stuff my thanks to you both ..all i need now is some reasonable weather to get some testing in :)

[kalps]

Is this JR or Futaba? JR is around 1500 plus or minus and 1530 for Futaba.. In most cases it won't be perfect but you need to use 1500 or 1530 on the TG to determine center and let it rule. If it is way off then there is sub-trim or something up in the radio. Make your mechanical adjustments from there off that point such as level swash, etc. In other words, you may be physically at zero on the collective stick but say 1522 on the TG. Move the stick till the TG says 1500 or 1530 for Futaba and the stick may be off a tiny bit. That's the way I set mine up.
Not really sure what you mean. Kindly elaborate. I am using Aurora 9 and i think it would be Futaba 1530.

Thanks.

[MarshallB]

I'm not sure where the Aurora would be! I would set the collective to mid stick using your servo monitor and look and see what the Total-G says the value is That may give you a clue as to where it should be. That may not answer your question but I hope it helps. If not I can try and get an answer..

[MarshallB]

Kalps, Here is one thing I did find in the Total-G Detailed Instructions..

It says this: "This is a choice between JR and Futaba to take into account their different “neutral” input pulse width settings. JR centers around 1500 and Futaba around 1530. Select the “Type” that most closely fits your radio gear. If in doubt leave it at the default “JR” setting."