SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
This thread is privately moderated by billpa, who may elect to delete unwanted replies.
Old Feb 05, 2013, 12:37 PM
Registered User
United States, OH, Loveland
Joined Feb 2007
354 Posts
Scale takeoff help

One of the guys wants to use the Guardian in his Cub to give him scale takeoffs. How should he set it up to keep the plane tracking straight on the ground but allow him to bring the tail up and be able to rotate for a nice scale takeoff? What mode should he use, 2D or 3D to give him scale takeoffs. Is this even possible?
sinowace is offline Find More Posts by sinowace
Reply With Quote
Sign up now
to remove ads between posts
Old Feb 05, 2013, 01:02 PM
Registered User
Joined May 2011
96 Posts
Can the Guardian be configured in this setup?

I've got a Sebart Mig 29 EDF with twin EDF and vectored thrust. It has a HH gyro on the rudder channel that only controls the rudder of the VT units, not the actual rudders (I think) It has dual rudder with one servo for each and a third servo that controls the rudder function of both VT nozzles. I had one rudder servo go bad so I bought a pair of Hitec's to replace them both (didn't want mismatched servo's) Then I found out that the Hitec's worked in the opposite direction from the oem servo's so now the rudders moved opposite the VT. You couldn't just reverse the servo because it would reverse all three servo's causing the same problem in the other direction so I replaced the VT servo with a third matching Hitec servo. Reversed the gyro and took two test flights, all was good. Then on the third flight it appeared that the gyro somehow reversed itself and from a hover it pirouted hard and drove into the ground. Not knowing what had happened I tried it again and it did the exact same thing. Now six months later I'm in the process of rebuilding the model and since I don't trust the $10 chineese gyro that came with the kit I'm considering installing the Guardian. I fly heli's so I'm very familiar with gyros both tail and 3 axis I'm just having trouble envisioning the wiring on this due to the extra channels and VT nozzles. Like I said before it's been about six months since I've flown this plane so I'm a little rusty on how everything was wired and programmed but I think it went like this.

Dual Aileron Sevo's connected independently? (They may however be Y'd)
Dual Elevator Servos (These should be Y'd)
Dual Rudder Servos (These should be Y'd as well)
Dual Elevator/Aileron Servo's on VT (Aux2 for one and Aux3 for the other)
Single Rudder Servo to control both VT (Y'd to other two rudder servo's and inline with gyro)

I wish I could remember how this was all connected. I think the rudder VT works all of the time but the gyro was set through FM2 and only controlled the VT nozzles not the actual rudders. I remember how it worked better than how it was wired. Normal mode was low rates and only rudder function of the VT. There was no way around that one because it shared a channel with the rudders. FM1 was mid rates and full VT for ail/ele/rudd but gyro was off. FM2 was high rates, full VT and gyro for rudder channel on. I think ail and elev VT servos go to aux 2 and aux3 then are mixed in with Ail and Elev functions in FM1 and FM2.

I know I could simplify it and have the Guardian control all aspects of the VT nozzles which is the most important in this application (would probably hover hands off) but I'm wondering If I could wire it to control both VT nozzles and actual control surfaces? At first I don't see how because it's 5 independent channels but I'd have to sit down and study it to be sure. I assume If it could be done that I would be trading off something like the ability to shut off VT. If I hooked everything via Y's then VT would always be on however it would reduce it from 5 to 3 channels making it work right? Am I right in assuming I only need one channel to control the unit itself (off/on/gain)?

I'm thinking it's likely going to need to by connected to the VT only through rudder, aux2 and aux3. Everything would stay the same expect the gyro would be replaced by the guardian and it would control the VT on all three axis instead of just rudder. Since the Guardian is limited to three channels it's either that or connect it so VT is directly wired the ail and elev and it will control all surfaces but the VT will be on all of the time.

Also I don't see any mention of digital servos being needed. With 3 axis sytems on a heli you need digital or the unit will burn out the servo's...does that rule apply to these units?

Thanks for any insight you can provide
supertoyz is offline Find More Posts by supertoyz
Last edited by supertoyz; Feb 05, 2013 at 01:19 PM.
Reply With Quote
Old Feb 05, 2013, 01:33 PM
Michael
United States, ME, Wells
Joined May 2008
1,066 Posts
Rigid Hook and Loop

I know the type to which you are referring and I think it would keep the Guardian constrained sufficiently. I concur about not using conventional "Velcro" type fastening...

My only concern with the rigid variety is the force needed to get the solid capture as well as to release the Guardian device. The plastic cover appears to be a somewhat loose fit.

I use the exterior grade 3M double-sided sticky tape and you do have to press the Guardian down, but not with as much force as I find I have to use with the rigid H&L stuff. Removing the Guardian, with the sticky tape, is generally a peel-back and/or slide a nylon Spackle knife...

If not going to be moved a lot, then I do not see a problem.

Michael
Quote:
Originally Posted by JayY View Post
I'm not using typical hook and loop, the product I linked to has a rigid attachment, no wobble.
Snowflake6515 is offline Find More Posts by Snowflake6515
Reply With Quote
Old Feb 05, 2013, 01:58 PM
Registered User
TheBum's Avatar
McKinney, TX
Joined May 2007
1,616 Posts
Quote:
Originally Posted by JayY View Post
I'm not using typical hook and loop, the product I linked to has a rigid attachment, no wobble.
Interesting stuff. Yeah, that definitely looks like it'd be a pain to detach. I find some of the regular 3M 4011 double-sided foam tape works well.
TheBum is offline Find More Posts by TheBum
Reply With Quote
Old Feb 05, 2013, 04:13 PM
KD0ZEQ
Dubjay's Avatar
United States, CO, Snowmass
Joined Nov 2012
192 Posts
2 channel

Does the eagle tree work o.k with just rudder and elevator? Or do you need to have the 3 axis for it to work right?
Dubjay is offline Find More Posts by Dubjay
Reply With Quote
Old Feb 05, 2013, 04:36 PM
Chasin' that Neon Rainbow
Grantham Kid's Avatar
Australia, QLD, Grantham
Joined Oct 2012
2,592 Posts
Naturally it is designed for all 3 axis, but yes, you can use just rudder or just elevator or both, pity to do that. Maybe a cheaper gyro would suit your purpose better?
Grantham Kid is online now Find More Posts by Grantham Kid
Reply With Quote
Old Feb 05, 2013, 05:17 PM
Registered User
United States, OH, Loveland
Joined Feb 2007
354 Posts
Scale takeoff help

Quote:
Originally Posted by sinowace View Post
One of the guys wants to use the Guardian in his Cub to give him scale takeoffs. How should he set it up to keep the plane tracking straight on the ground but allow him to bring the tail up and be able to rotate for a nice scale takeoff? What mode should he use, 2D or 3D to give him scale takeoffs. Is this even possible?
Does anyone have any answer?
sinowace is offline Find More Posts by sinowace
Reply With Quote
Old Feb 05, 2013, 06:34 PM
Registered User
ricoalonso's Avatar
USA, KS, Derby
Joined Mar 2003
1,474 Posts
Quote:
Originally Posted by sinowace View Post
One of the guys wants to use the Guardian in his Cub to give him scale takeoffs. How should he set it up to keep the plane tracking straight on the ground but allow him to bring the tail up and be able to rotate for a nice scale takeoff? What mode should he use, 2D or 3D to give him scale takeoffs. Is this even possible?
Quote:
Originally Posted by sinowace View Post
Does anyone have any answer?
sinowace,
IMO, the best way to use the Guardian 2D/3D so that it will help the plane to have a scale takeoffs is to set it to 3D Rate Mode (HH off). In this mode, the Guardian will only be to smooth out wind turbulence and help resist sudden attitude change due to wind but most of the controls will be left to the pilot.

Unfortunately, once you set your 3D to Rate Mode, you cannot switch to 3D HH mode via the mode switch. You can still switch from 2D-OFF-3D but your 3D will always be in Rate Mode.

Hope that helps.
Rico.
ricoalonso is offline Find More Posts by ricoalonso
Reply With Quote
Old Feb 05, 2013, 06:34 PM
Foam Temple Pilot
JayY's Avatar
United States, NC, Raleigh
Joined Sep 2012
528 Posts
Deleted
JayY is offline Find More Posts by JayY
RCG Plus Member
Last edited by JayY; Mar 19, 2013 at 09:01 PM.
Reply With Quote
Old Feb 05, 2013, 06:48 PM
Chasin' that Neon Rainbow
Grantham Kid's Avatar
Australia, QLD, Grantham
Joined Oct 2012
2,592 Posts
Quote:
Originally Posted by JayY View Post
Nice clean installation, I'll be interested in your flight report.

Because I like to be able to quickly remove the Guardian so I can conveniently access the USB port, I mounted mine using heavy duty hook and loop strips, which hold the Guardian very tightly to the model.
I have never had a problem with velcro myself. I use it with gyros in my other planes (3) and also my receivers. I bought a 5 meter roll of each (hook and loop) some years ago and I even use it for my vidcam on my models. I find it very secure and if I had any doubt I would not use it. OK, I used double sided tape in my helicopter, but that is a different pony altogether. I find the double sided tape from Aldi works well but it is hard to get it to release. It is best doubled or tripled.
Grantham Kid is online now Find More Posts by Grantham Kid
Reply With Quote
Old Feb 05, 2013, 07:58 PM
Foam Temple Pilot
JayY's Avatar
United States, NC, Raleigh
Joined Sep 2012
528 Posts
Deleted
JayY is offline Find More Posts by JayY
RCG Plus Member
Last edited by JayY; Mar 19, 2013 at 09:07 PM.
Reply With Quote
Old Feb 05, 2013, 08:18 PM
KD0ZEQ
Dubjay's Avatar
United States, CO, Snowmass
Joined Nov 2012
192 Posts
O.k thanks for the replies.
Dubjay is offline Find More Posts by Dubjay
Reply With Quote
Old Feb 05, 2013, 09:16 PM
Registered User
United States, TX, Richardson
Joined Oct 2011
301 Posts
I have a Guardian installed in a profile foamy which has no rudder, just ailerons and elevator. I have been afraid to fly any plane that has ailerons because of the difference in control from 3 channel. Like with ailerons you have to give it opposite direction to bring it back to level after a turn.

With the Guardian installed and set to 2D mode, WOW, is it ever easy to fly! To turn I just give it some aileron and hold it during the turn, and when I want to go back to straight flight, I just let the stick go and the plane levels out just perfectly!

Before I had the Guardian installed, on one of my flights I stupidly let the plane fly right into the sun - while I was doing a turn. When I recovered from being blinded by the sun, the plane was upside down and heading for the flight line. I somehow managed a very tight inside loop and got it headed out over the field again - scared the "you know what" out of me!

OK, with that background, here's my question. When flying in 2D mode, does the Guardian prevent me from banking more than 45 degrees? I am not sure, but on the 3 flights I made after installing the Guardian, it seemed to do that (restrict me to 45 degrees max on a bank to turn). If that's the case, I sure do like it. That would have saved me from the near disaster I mentioned above. If I want to roll the plane more than 45 degrees, like 180 to fly upside down, or do a series of rolls, I can just switch the Guardian to 3D mode, right?
fotoflyer is offline Find More Posts by fotoflyer
Reply With Quote
Old Feb 06, 2013, 08:12 AM
Your customer
Silverexpress's Avatar
Berkley, MI
Joined Dec 2009
1,384 Posts
Quote:
Originally Posted by Grantham Kid View Post
Naturally it is designed for all 3 axis, but yes, you can use just rudder or just elevator or both, pity to do that. Maybe a cheaper gyro would suit your purpose better?
Per manual, minimum required connections are aileron and elevator. These two control surfaces are used by the 2D control loop to level the plane. Plugging only one in will leave an open loop condition - may lead into an uncontrollable spin in 2D mode.

The plane uses the aileron gyro (roll) and elevator gyro (pitch) to sense that roll and pitch have "occurred" and that the plane as been returned to level (accelerometer) - reducing corrections to zero as necessary. If it doesn't get this feedback it will continually apply the necessary control throws to achieve this, but since you've left one surface unplugged - it may never reach that point.
Silverexpress is offline Find More Posts by Silverexpress
Last edited by Silverexpress; Feb 06, 2013 at 09:29 AM.
Reply With Quote
Old Feb 06, 2013, 08:22 AM
Michael
United States, ME, Wells
Joined May 2008
1,066 Posts
Aileron vis-a-vis Rudder

I believe that the several Radian three-channel posts indicated success (with one exception - lack of inverted flight capability).

The rudders were connected to the aileron channel of the Guardian; i.e., plane: rudder & elevator, Guardian: aileron and elevator.

Michael
Quote:
Originally Posted by Silverexpress View Post
Per manual, minimum required connections are aileron and elevator. These two control surfaces are used by the 2D control loop to level the plane. Plugging only one in will leave an open loop condition - may lead into an uncontrollable spin in 2D mode.
Snowflake6515 is offline Find More Posts by Snowflake6515
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Can I control Guardian stabilizer with DX6i? njwxyz Eagle Tree Systems 9 Jun 02, 2014 12:17 PM
Discussion GPS 2D Plots incomplete, 3D OK jackerbes Eagle Tree Systems 1 Oct 23, 2011 09:42 PM
Discussion Premier 1st generation, Gen 2 Vector unit, 2D or 3D motor unit lanternfly RC Kites 0 Oct 05, 2011 09:42 PM
Data 2d or 3d wing ribs? Marty7n Beginner Training Area (Aircraft-Electric) 56 Sep 22, 2011 04:06 PM
Discussion 3View to 3D to 2d techasist CAD/CAM 0 Mar 27, 2011 12:19 AM