rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 295 ONLINE 28 EVENTS SEARCH REGISTER  START HERE
 
1 page984 viewsPOST REPLY
GrandRC . CanoMod . Futaba-RC

.
.
Avant Aurora - EFX - FX > Interaction on rolls?
 
 
ghettotige
Heliman
Location: Weymouth, dorset UK

Hi guys, overall the Auora is great tracks amazing through loops and is so stable when you want it to be.
I like to do alot of backwards rolling circuits but they are proving a little tricky with this machine. While rolling the tail seems to spiral or corkscrew I think elevator input.
Is the best practice to add a mix to the radio or do I make a change to the phasing block, or is there something else to check?
currently flying radix stick bangers, spectrum radio, spartan gyro
Cheers guys.

Mike Freeman,
Avant Aurora,
Align Trex 700,600,500,450
All the gear and no idea!!!!
06-24-2008 09:23 AM
 
 
MrMel
Elite Veteran
Location: Lidingo, Sweden

Have you enabled EXP=ACT in the swash menu in the Radio, else thats the cause, re-check your total pitch afterwards since it will be less.

Without it you cannot get it perfect, it will adjust for the circular movement of the servo.


Team Autopartner - Team pilot
06-24-2008 10:05 AM
 
 
Augusto
rrAdvertiser
Location: San Diego, CA

That can be easily adjusted in the programmable head.
Please go to page 34 of the manual and read about the phasing adjustment.

Quote 
"If you want you can also adjust the phasing to match your blades lead-lag angle and eliminate any tail corkscrewing during rolls if your blades have some. If you need to correct you can start with about 1 degree and build up from there."

You can pretty much make it perfectly straight during rolls.
Also there are some high-end radios that allow you to do the same via programming of the phasing angle.

Augusto.

Avant Aurora Ultimate
06-24-2008 10:11 AM
 
 
darrens
Key Veteran
Location: United Kingdom

You need to set your phasing so that there is no interaction between elevator and aileron. Also, have you set the end points individually for the 3 cyclic servos using a swash balancer, this will have an effect if you are punching full pitch in either direction.

He who dies with the most toys is the winner!
06-24-2008 10:34 AM
 
 
ghettotige
Heliman
Location: Weymouth, dorset UK

Thanks guys, after flying tonight found that stationary rolls on the spot are perfect, the spiral efect just seems to occur while traveling. Could this still be a phaseing issue or it could just be me adding inputs on the sticks ( alot going on in a backwards rolling circuit) Don't want to mess with it if it ain't broken To be fair I like a simple setup everything at 90deg, all radio settings at default, but if end point settings for cyclic interaction and phasing adjustments are seen as normal setup I will go ahead and mess.

Mike Freeman,
Avant Aurora,
Align Trex 700,600,500,450
All the gear and no idea!!!!
06-24-2008 10:26 PM
 
 
airboss
Elite Veteran
Location: OC ,california

I had a the pleasure of flying the Finless Aurora last sunday, that is very nice heli flew simmilar to the N9s I currently own but responded to control with crisp authority. I will be adding one to my fleet.

Synergy N9..FlyBlackstarr.org.., Helifreak.com..,Insane Canopy..
06-24-2008 10:48 PM
 
 
creightoncarr
Veteran
Location: Missouri City, Texas - USA

Definitely normal to adjust cyclic servo endpoints on a CCPM machine to get rid of interactions at full negative and positive pitch. It's extremely unlikely to solve your corkscrewing problem, however. If your stationary rolls are spot on I would venture to guess that the corkscrewing you are seeing is unwanted control input. Are you doing your rolling circuits without any elevator input at all? I've always done my rolling circuits with a combination of aileron, elevator and rudder inputs. If I don't coordinate the elevator and rudder inputs perfectly then my tail will corkscrew as well.
06-24-2008 11:18 PM
 
 
darrens
Key Veteran
Location: United Kingdom

As creightoncarr said, if your stationary rolls are ok, your phasing should be right, but have you checked it and are you familiar with how to check it?

He who dies with the most toys is the winner!
06-25-2008 01:00 PM
 
 
pinewaves
Heliman
Location: Lawrence, NY - USA

Quote 
set your phasing so that there is no interaction between elevator and aileron.

hmmmmm, I don't know about that one...

Most of the time when you hear the term "interaction" it refers to undesired eCCPM inputs to the swash. The eCCPM mixing progam in your radio assumes the movement of each servo has equal affect on the swash. Because of things like unequal rod lengths between swash and the bellcranks the eCCPM calcs can be off a little. The effects of interaction are usually more noticeable at the extreme ends of the collection throws.

Say for example you're sitting in hover on a calm day and you decide you want to do a quick climb out. If instead of the heli climbing straight up with only minimal cyclic correction, it starts to bank to the right, you most likely have some swash interaction you need to tune out. That being said, eCCPM helis, at least the 120 degree flavor, will alway have some degree of interaction, you just tune out what you can and fly through the rest.

Quote 
Definitely normal to adjust cyclic servo endpoints on a CCPM machine to get rid of interactions at full negative and positive pitch. It's extremely unlikely to solve your corkscrewing problem, however

I'm with you on that one.

My understanding is that phasing adjustments are used to advance the point at which the swash influences the rotor blade pitch. The standard rotor head is setup for 90(degrees) of phasing, meaning, the effect of swash inputs on the rotor head are realized 90(degrees) from the input. For the most part this is only true with stiffer blades. The more flexible the blades are, the more the lead/lag angle decreases. Because of this, when you roll the heli it will appear to corkscrew through the air because the roll axis is not in line the the tail boom. This alignment issue can be corrected by adjusting the phasing. May help to a look at my cheesy diagram.




Note, different blades can require different phasing.

Just my 2 cents.
06-25-2008 02:03 PM
HOMEPAGE  
 
 
darrens
Key Veteran
Location: United Kingdom

As this guy is flying an Avant Aurora, it would be fair to assume he is running stiff blades (afterall, it is supossed to be the ultimate 3D machine so I doubt he's running woodies!)and his phasing should be set at 90 degrees with his roll axis in line with the boom. It is at this point I would suggest setting it so there in no interaction between the cyclic controls and it should at least prove to be the benchmark starting point with very little adjustment required therafter. Further adjustment can only be done by trial and error moving slightly left or right of this point, or do you know of some way for calculating offset based on given perameters and blades used?

He who dies with the most toys is the winner!
06-25-2008 03:07 PM
 
 
pinewaves
Heliman
Location: Lawrence, NY - USA

Quote 
it would be fair to assume he is running stiff blades

yep, he says he's
Quote 
currently flying radix stick bangers

but blade stiffness is only one of a many factors that can contribute to the overall lead/lag effect.

Quote 
Further adjustment can only be done by trial and error moving slightly left or right of this point, or do you know of some way for calculating offset based on given perameters and blades used?

you're absoultly right, that would be the best approach.

I was really just responding to the post that seemed to be conflating the terms phasing and interaction.
06-25-2008 03:29 PM
HOMEPAGE  
 
 
darrens
Key Veteran
Location: United Kingdom

OK, I guess it's worth stating that interaction can come from 2 factors;

1. Incorrect phasing can cause interaction between elevator and aileron inputs when comparing pilot request to cyclic movement

2. Unequal end points (physical not radio settings) can cause interaction at full pitch throws

But remember, when you type
Quote 
hmmmmm, I don't know about that one...
, it gives the impression that you think someone is talking sh*t rather than providing constructive assistance

He who dies with the most toys is the winner!
06-25-2008 03:50 PM
 
 
MrMel
Elite Veteran
Location: Lidingo, Sweden

Quote 
2. Unequal end points (physical not radio settings) can cause interaction at full pitch throws

Try a JR with and without EXP=ACT at full/min pitch with full aileron and see what happens.

EXP=ACT will correct the circular movement of the servohorn, when you are at full pitch the servo horn is already off-set, the one moving towards center have to move less then the servo horn moving away from center to archive same distance.

With EXP=INH you will get interaction, regardless how good your physical & endpoint setup is.


If you have a 12FG/Z/MZ radio there is a whole faq to get a machine "interaction" free, which happens to be the big power of the high-end Futaba radios.

http://www.14mz.com/faq/faq-14mz-q845.html


Team Autopartner - Team pilot
06-25-2008 04:03 PM
 
 
pinewaves
Heliman
Location: Lawrence, NY - USA

Quote 
it gives the impression that you think someone is talking sh*t rather than providing constructive assistance

nope, that's not the case at all. It just means that "im not sure" that I agree.

Quote 
Incorrect phasing can cause interaction between elevator and aileron inputs when comparing pilot request to cyclic movement

I can see what you mean if you look at if from the perspective of heli movement compared to pilot request. The effect is the same. I just see it as two different causes resulting in the same effect.

For example, we know for a car track strait down the road the tire pressure must be basically even. If I dramatically lower the presure in the front right tire the car would tend to pull towards the right. I would not describe that as a "wheel alignment" issue just because it feels that way from the drivers perspective. But one could.

Not looking for a debate, just clearing up the reason for my post.
06-25-2008 05:09 PM
HOMEPAGE  
 
 
ghettotige
Heliman
Location: Weymouth, dorset UK

Almost lost me there guys LOL, I sell t-shirts for a living not rocket engineer.
Basicaly from hover give it full pitch and look for a tendancy to roll left or right, this would be interaction and can be corrected by the EXP=ACT in the spectrum pitch curve menu or adjust end points.
In a taveling roll if the heli tends to pitch up and come to a halt this would be phasing and is adjusted with the progamable head.
Am I about right?
In answer to an earlier question yes I use all controls in rolling circuit and to be fair I can fly through any interaction and automatically correct (yes Iam that good LOL) but I noticed how well the auora tracked through a loop, I have never had a heli feel like that, Raptor 50/90 trex 450, 600, 600n,500 E, knight 3d , synergy and 600n with v-bar (needless to say a few helis over the last 18mnths).It just made me think I might be able to adjust things to get it to fly perfect or as close to the sim as possible since I spend at least 14hrs a week on pheonix.

Mike Freeman,
Avant Aurora,
Align Trex 700,600,500,450
All the gear and no idea!!!!
06-25-2008 08:42 PM
 
 
ghettotige
Heliman
Location: Weymouth, dorset UK

Sorry ment to add, Is there any other moves I should try to get a better idea of flight characteristics.
Sorry for the spelling by the way I am Crip at it lol

Mike Freeman,
Avant Aurora,
Align Trex 700,600,500,450
All the gear and no idea!!!!
06-25-2008 08:44 PM
 
 
Chopper
Key Veteran
Location: Stow,Oh- oops, I mean St Louis, nope Stow again

I believe your heli may have a balance problem. Most likely tail heavy. If it is tail heavy, it will do what you are describing.

Although you haven't mentioned it, will the heli fly without correction fast forward flight, upright and inverted at different pitch inputs? That will tell you alot.

You can fly tail heavy, but you will need to add some mixing to stop the tail down tendencies. This means that the swash will not be perfectly level all the way through the range, but the heli will fly straight upright and inverted. Or...you can get a bigger battery to add nose weight ;-)

If your balance is neutral,or slightly nose heavy then look to some interaction issues or phasing.

This is all assuming that it is not your thumbs.......

Paul Soha is a Futaba Team Pilot , Aurora Team Pilot, Wildcat Team Pilot, SAB blades
06-25-2008 09:58 PM
 
 
ghettotige
Heliman
Location: Weymouth, dorset UK

pretty sure the balance was correct at the time of build but will recheck, Unfortunately wind has increased the last couple of evenings so no flying , I will report back with some findings.
Ark at me getting all F3c LOL

Mike Freeman,
Avant Aurora,
Align Trex 700,600,500,450
All the gear and no idea!!!!
06-26-2008 09:07 AM
 
 
1 page984 viewsPOST REPLY
A Main Hobbies . Boca Bearings . Modefo's RC Helicopters

.
.
Avant Aurora - EFX - FX > Interaction on rolls?
  UPDATE SCREEN   PRINT TOPIC Advertisers 

Subscribe to This Topic

Wednesday, October 8 - 8:37 am - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie