Originally Posted by t.edwards

That's two points you've mis-understood and taken out of context.

Care to enlighten me?

Originally Posted by choochoo22

...
That would be nice but, not really. Remember, Guardian is only trying to hold position while the stick is centered. Clearly, if you are trying to roll the plane the stick is not centered. Once you move the stick off center the plane is free to move on all three axes, not just roll, so the nose is free to droop down. You can demonstrate this on the ground. ...

From what I remember of playing with the Guardian on the ground in 3D head holding and direct rate mode, with the aileron stick off center for a roll, Guardian will not try to keep the nose up with head holding, but if the nose is dropping, Guardian will still try to counter (slow down) that dropping in rate mode (if still upright, counter the nose dropping with the elevator in rate mode, if in knife-edge, counter the nose dropping with the rudder in rate mode). So any nose droop will slow down (easier for pilot to correct), but Guardian will not try to go back to the original nose up/down angle by itself.

This lack of head holding in all axes when the aileron or elevator stick is off-center surprised me at first when I was testing the Guardian, but then I reread the Guardian documentation and saw this mentioned on page 2.

Originally Posted by flying-llama

Guardian will not try to keep the nose up with head holding, but if the nose is dropping, Guardian will still try to counter (slow down) that dropping in rate mode

True. I wasn't thinking about the rate component of the correction but that will counter gravity a bit. As you point out, however, it won't hold attitude this way as rate mode only responds to the rate at which it is not holding attitude.

I spent a rather frustrating evening trying to program my DX8 with a 6 channel Rx using GEAR for GAIN & FLAP for MODE, ailerons are Yed. I thought it should be simple. Turn up the gains so I could confirm direction. Inhibit GEAR switch & mix from AUX3 to GEAR. Well I did confirm direction & decreased trims; but in the full flap position the aileron went to full travel, as if it were a flap(flaperons were NOT turned on). So I tried inhibiting flap switch & mixing AUX2 to flap. Nada.
Could someone who has done this correct me please.

Originally Posted by DavidN

I spent a rather frustrating evening trying to program my DX8 with a 6 channel Rx using GEAR for GAIN & FLAP for MODE, ailerons are Yed. I thought it should be simple. Turn up the gains so I could confirm direction. Inhibit GEAR switch & mix from AUX3 to GEAR. Well I did confirm direction & decreased trims; but in the full flap position the aileron went to full travel, as if it were a flap(flaperons were NOT turned on). So I tried inhibiting flap switch & mixing AUX2 to flap. Nada.
Could someone who has done this correct me please.

I have a plane set up that way. You don't need any mixes for this. Go into the "switch select" menu. Inhibit the "gear" switch and assign "knob" to "gear". I also found it convenient to reverse the gear channel to have the knob work the way I prefer. It might be worth a few minutes to make sure all the connectors are plugged-in correctly in and out of the Guardian.

Here is a basic question for someone. What is the difference between 2D heading hold and 3D heading hold?

I have a question or two, followed by an explanation of what I am up to. If "billpa" in particular is reading, perhaps he could help me out.


First, a Clarification: I use the term "Tx servo travel" as what the Tx outputs and the Guardian therefore sees. It does not refer to the end result of driving the physical servos on the airframe.

I know that the Master Gain (which I drive from the AUX2 channel on my DX7) has the stated range from -100% "Tx servo travel" through +100% "Tx servo travel", with a mid-channel position being essentially Master Gain = 1.

Let us now set the "Tx servo travel" to, say, 150%.

What happens between the +100% and +150% range? Does Guardian keep multiplying the hardware-selected Gains beyond their original settings? Or, does it simply stop at some multiplier when it sees >= 100% "Tx servo travel"?

What happens between the -100% and -150% range? Is there anything significant about the Guardian seeing a precise -100% input value? Or, by that time is the Master Gain such a small value that it has divided the hardware-selected Gains down to insignificance so that it appears that the Guardian is "off"?

What is the actual response curve of the Guardian's Master Gain operation, i.e., is it linear from whatever it does when it sees +100% through -100%, crossing "1.0" at the neutral point of "Tx servo travel" being "0"?

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So, why would I (or anyone else) care about this? Well, as an engineer, I like to understand stuff in general. More specifically, I am using the AUX2 switch and slider to manage Master Gain on my Guardian. My aircraft typically employ flaperon/spoileron setups and the DX7 appropriates the Flap Switch. I finally figured that out, after messing around for quite awhile, thanks to this Forum!

My AUX2 works well:I flip it forward to enable the Guardian to do its job and I can use its trim function (slider). Flipping it back, if the trim is set sufficiently back,
will essentially disable the Guardian, as the Master Gain multiplier is either "0" or very low.

As I refine things, and move around to different aircraft, I will determine where
set a SubTrim position in order to ensure that when the AUX2 is flipped back, the Guardian will see -100% or greater, regardless of where the trim(slider) happens to be. Flipping the AUX2 switch forward will then give me an enabled Guardian with something like, say, +70% to +100% to effect minor in-flight adjustments, controllable by the range of the trim(slider).

Clear as mud, eh!

Getting this Guardian has finally prompted me, after several years of owning the DX7, to really try to understand what Range, Trim and SubTrim can really do.

I made a little test thing with an old S3004 servo and a Degree Wheel, plus a piece of wire attached to the servo to serve as a pointer. I then went through combinations of servo travel (100%, 125%, 150%) and marked the angles for maximum travel, the SubTrim range, and the normal Trim range at each extreme and the centered position. It is very informative - I may write up a little story, with pictures, and post it somewhere, sometime.

Having done this bit of research, I have a Degree Wheel for a specific setup, say, the normal +- 100% "Tx Servo travel" case, and superimpose it upon another one which reflects the Guardian's supposed +- 100% input range. This allows me to figure out the Sub Trim to use which will give me the desired behaviour, e.g., AUX2 flipped back to "bypass" Guardian's influence, AUX2 flipped forward to enable Guardian and allow Master Gain adjustment.

I know this is really a bit of overkill, but this is a hobby, right?


P.S. I have combed through EVERY posting in this Forum and made up notes (4 pages!) for myself. In some cases, I used exact quotes, sometimes doing minor or severe editting and in many cases I corrected my earlier notes when new, better or corrected information appeared. It has been a lot of work but I have enjoyed it. I intend to now keep abreast of all of this stuff and further refine my notes. I am tempted to post a copy in here, in case someone else might benefit and not have the patience or obsession to go through 179 or more pages in here! Any interest?

Definitely interested! Post away...

Originally Posted by DavidN

I spent a rather frustrating evening trying to program my DX8 with a 6 channel Rx using GEAR for GAIN & FLAP for MODE, ailerons are Yed. I thought it should be simple. Turn up the gains so I could confirm direction. Inhibit GEAR switch & mix from AUX3 to GEAR. Well I did confirm direction & decreased trims; but in the full flap position the aileron went to full travel, as if it were a flap(flaperons were NOT turned on). So I tried inhibiting flap switch & mixing AUX2 to flap. Nada.
Could someone who has done this correct me please.

David, If you can wait till this weekend, (and I'm home). I have a DX8, setup with what I believe is a AR600 in a e-flight Apprentice 15e. I can send you the setup in an email and you can tweek it to better suit your model. Not remembering what the names of the switches are I can tell you that the 3possition switch on the left side is set to 2D-off-3D. and the knob is set to adjust gain. I also have a switch on the right side that will drop the throttle to ZERO, to protect me and others on the flight line, and the aircraft during an un-schedualed landing.

Send me your email, please, if you want.
Ken K

Originally Posted by DownUnderPilot

Definitely interested! Post away...

OK, here are my notes. These will probably never be completed I am always open to learning more.

They are based upon this Forum, all 179 or so pages, so far. I have tried to understand, modify, condense, re-visit, whatever ... over the past few days, since I got my Guardian. Lotsa beers required!

If I have taken a quote from someone and modified it for my personal use, please forgive me. I mean no harm.

Over my lifetime, I have found that I often have to actually write something down in order to really think it through. The Guardian, and some similar gear, is an incredibly interesting and powerful new consumer technology. It begs to be understood.

Aside: Although this is an "apple and oranges" comparison, my son informs me that the INS box on the Bombardier Challengers he flies costs in the neighborhood of $200,000USD ! Yes, it does do a bit more than, say, a Guardian; but, when the underlying gyro and accelerometer technology was first brought to the commercial market, could anyone ever have imagined that we would be able to shell out the equivalent of a couple of cases of beer and have a little piece of this in our toy airplanes? What a time to live (and play) in!

Originally Posted by jj604

Prof, your brain is fine.

You can't get 3 functions from the 2 position gear switch to give you 2D and 3D. Gear gives you either -100% or +100%.

Then you create a mix that when OFF doesn't affect the gear switch, when ON it gives you always 0% = OFF

So yes, you do need two switches, GEAR -> 2D or 3D and MIX -> 2D/3D (as selected by the Gear switch) or OFF.

How will this work when you have retracts?

Originally Posted by sinowace

Here is a basic question for someone. What is the difference between 2D heading hold and 3D heading hold?

From reading the manual and playing with Guardian on the ground:

3D heading hold: heading hold on all 3 axes. Correction is via the "same" channel as the axis: yaw heading hold affects the rudder servo, roll heading hold affects the aileron servo, etc.

2D heading hold: Only heading hold for YAW axis, and the heading hold correction is via AILERON servo (the rudder servo still acts with a rate gyro to yaw changes).
Like 2D in general, the aileron and elevator servos are (also) used to try to keep/hold the plane "level" (as defined by when you reset level), so may be thought of as "heading hold" to the heading of level.

To me, 2D heading hold seems a bit "wierd" (I fly at quite slow speeds and do flat turns with a rudder), so I will probably not use 2D heading hold.

Originally Posted by sinowace

Here is a basic question for someone. What is the difference between 2D heading hold and 3D heading hold?

flying-llama pretty much said it but here it is again worded differently.

3D "heading hold" is a bit of a misnomer, it might be better described as "attitude hold". When the stick is centered all three axes attempt to hold the plane in its current attitude. A theoretically perfect aerobatic plane should have neutral stability, it should stay in whatever attitude you put it in and each control axis should not affect the others, eg: rudder should not affect roll. 3D mode makes the plane behave much closer to this ideal. For various reasons it isn't exactly perfect but it is definitely an improvement for any plane I have. It's a real treat to fly and maybe why most of us keep adding Guardians to our fleet.

2D heading hold is like a real plane on autopilot. Guardian keeps the wings and pitch level and maintains the heading by using ailerons to bank the plane onto the correct heading. The pilot may override these actions by using elevator to adjust pitch and aileron to change heading. (Rudder works but isn't very useful in 2D.) Aerobatics are not possible as both the pitch and roll angles are limited and prevent the plane from going very far from level. This mode has a number of applications but isn't much fun for general flying. Some uses include; training, camera planes, FPV, recovery from disorientation or flying too far away, I like it for landing, some use it for take-off.

Both modes offer substantial resistance to turbulence and gusts.

Thanks for posting your explanation of heading hold.

I must add this to my notes - at least until someone convinces me that there is some better explanation!

Can I get a bit of help please? I apologise in advance for not having read the entire thread!!!

A friend purchased 2 guardians and I agreed to do the setup and configuration for him. We both have Futaba 9C radios, which make this arrangement ideal!

My questions are, how do you set up the guardian to be

a) switchable on and off from the radio
b) adjustable (say with a slider or knob) on the radio

and optionally
c) Can it be configured to switch from 2d mode to 3d mode in flight (say take off on 2d and then switch to 3d)?

I read the instruction manual but it's not entirely clear to me.

Thanks
Dean