Silverexpress

My Feedback: (1)

HH (Head Holding) Mode is used to return an axis to a reference point. In this case your using a gyro unit that can only correct a single axis. Thus, if in HH mode the gyro senses even a minute rotation, it will start to deflect the control surface in an attempt to return itself to a set reference point. Since your aircraft is standing still, or in your hand, or on the ground slowly moving, the gyro will be prevented from returning to that setpoint. However, it will continually add more and more deflection in its attempt. Your particular gyro has no way of knowing that the plane is not flying. In the air it's a different story, nothing prevents the gyro from returning back to a set orientation. It's hard to see all this happening because - one it's moving, two it's flying, and three your eyeball is not next to the control surface to see the corrections being applied by the gyro.

You set the reference point by placing the control surface's stick to neutral after moving it - this is represented by your aircraft while it is in the air as a new orientation or heading. The control surface would be the one you have your single axis gyro attached to. You give a new reference point every time you move the control stick. Just a note, but at first powerup, the initial reference point(s) would be the current orientation the plane is at. If you pick it up and move it, the gyro senses the changes in rotation and so deflects the control surfaces.

landeck

My Feedback: (1)

Chuck, for one thing you have the HH gain much too high. At most it should be 70%. Try it with a 60% value and see it the problem still exists.

Bruce

dditch

IN heading hold, you are doing NOTHING to the plane the way that some people describe how to take off.

In my opinion, you are not learning anything. PLUS, in heading hold, quite often, I find that you have to dial down the travel adjust or dual rates otherwise, when you DO touch the rudder, it's way to sensitive. This all depends upon the gyro and your setup. Often, guys will relate their single experiance with gyros and say it applies to them all. Well, I've experimented with about 20 different gyros from mine and other people's planes over the past years so I know that in rate mode, you are less likely to start out in trouble.

Rade mode feels more like the natural flight charactoristics of your plane. It won't have an effect from dead stop, especially if your wheel is lose or you fly with a tail skid (like a WWI bipe) but you should be spooling up slowly anyway. With rate mode, you still have to fly the rudder and learn it, but quick sudden movements are damped.

My opinion is to start your venture into RATE mode and it will cause less problems starting out. Some gyros want to initialize in Heading hold mode though. Not all, but some Futaba Gy401 gyros do this.
http://www.mycoolrc.com/gyro/indexnew.html

BarracudaHockey

My Feedback: (11)

Keep the airplane still and your finger off the rudder stick till the light stops flashing when you power it up. If you can't see the light just wait several seconds, you will see the rudder bounce a bit when the init is done.

If it drifts like that just toggle it in and out of HH mode 3x quickly, that will reinitialize the gyro.

dditch

Basic setup on a DX6i,
This is just specifict to DX6i but does not cover all the aspects of gyro use only how to program the radio for it.
[youtube]http://www.youtube.com/watch?v=snZ1yoFjkbY[/youtube]

warhwk

My Feedback: (3)

I generally do not resurrect old threads, but this has been one of the most informative I have ever run across. Big thanks to dditch and Ben Lanterman and many others who have tirelessly assisted the gyro newbies.
I just installed a Detrum GY48v on an expendable Stik and wanted to keep the dialog open as I explore using a gyro on rudder.
My purpose for the gyro is for ground loop control for several Warbirds I own. Our runway is paved and fairly narrow. Last year I ground looped a 60 size P51 into the safety fence just as the tail lifted on take-off. That was with a quartering crosswind. Since then, I have avoided flying the P-51 on anything other than days that have wind perfectly down the runway.

My initial gyro setup on the Stik was mixed to the gear switch (CH5). ON was 60% gain on RATE MODE: OFF was 3% AVCS

Observation Take Off: My Stik is very well behaved on take off, and with a rare no-wind day, I did not push the gyro very hard. Take off's with and without the gyro enabled were similar. The Stik still pulled slightly one direction with the application of full throttle. What I did notice is how much faster I could taxi without the plane getting squirrely. In RATE mode, I could slowly advance the throttle all the way to Take Off. Of course, if you punch the throttle before the plane has rudder authority, it will still pull, at least initially. This is exactly what I want for my Warbirds. I do not plan on using AVCS MODE as I know I could never keep my thumb off the rudder.

Observation Flying: RATE MODE worked just as expected. I had no issues and never felt the gyro was fighting my inputs. I usually have to put in a little rudder during loops with my Stick to keep it from cork-screwing, but with the gyro ON, the loops started and ended on the same plane. Nice!

Observation Knife Edge: My Stick has terrible coupling in both Pitch and Roll. Attempted Knife Edges put the Ugly in Ugly Stick. LOL (couldn't resist ) Surprisingly, with RATE MODE On, the gyro on Rudder took care of all the roll-coupling leaving only pitch coupling to deal with. I was not expecting that at all!

Observation Landing: Similar to my take off experience. It really helped reduce the tendency to dance at the end of the landing roll out and I could taxi back at any speed I chose.

I am much more confident in putting a gyro in my Warbirds after testing with the Stik. Here is where I picked up my GY48v. http://www.hobbypartz.com/60p-dy-101...ProductReviews The video's from dditch were very informative and answered most of my questions. http://www.mycoolrc.com/gyro/indexnew.html

bunsen

Warhwk

Wondering if you installed a Detrum GY48V in your Warbirds and what was the result?

I am going to try a GYRO in "Rate Mode" as you did, for exactly the same reasons. Was looking at the DETRUM GY48V or a GY401 or a CORTEX DEMON (which is a lot more $$).

warhwk

My Feedback: (3)

Bunsen, I put the Detrum in my TF Mustang and use it in rate mode with about 60% sensitively. It completely cured the tendency to turn hard left when the tail wheel leaves the runway. They're currently on sale for less than $7

bunsen

Thanks ever so much.

Time to try a GYRO in my 29% BU-133 and if it works in the 1/5 Scale Spartan Executive.

Ray

Aerocal

I dont think I posted on this topic before but since it is revisited Ill chime in.
Havent used a one axis gyro on fixed wing much but I have a lot of exprience with helis. The Detrum gyro works fair but its definitely not as solid as a Futaba 401. It is after all a cheap copy.They may have gotten better in the 5 years or so since Ive used any. When it comes to cheap gyros it is many times reflected in their performance.
The one other thing that greatly enhances performance of a 401type gyro is being sure
the surface linkage allows the limit setting on the gyro to be at least 100. 120 is better if possible. If you have to turn the limit down much below 100 the gyro loses resolution and gets lazy.
IIRC and you are using a Futaba 401 use caution on where it came from. For a time there were alot of actual counterfeits floating around and some of them performed like crap.
The type of foam tape you mount them with can make a huge difference also. They can be fairly sensitive to vibration.

KurtS

I know this is an old thread, but I’ve read most of it and haven’t found an answer to an issue I’m having.

GY401 on the rudder works great in rate mode. Have it set to about 30% because if I use more than that and the rudder twitches.

HH is a different story. When in that mode the rudder doesn’t twitch back and forth, but very slowly the servo inputs left rudder. Turn the gyro off or go to rate mode and it centers.

I power up the TX in HDG mode, don’t move the airplane for 5 sec, and have a solid red light. All good so far. I have DS off and am running an HS-645MG on the rudder.

The above issues with the rudder twitching and HH slowly feeding in left rudder only happen when the engine is running. (30cc gas). Engine off and HH keeps the rudder centered unless the fuselage is moved.

Any thoughts as to why or where to look?

thanks

Kurt

BarracudaHockey

My Feedback: (11)

Yep, its doing exactly as its supposed to.
Here's a tip. Don't use heading mode on a fixed wing plane.

KurtS

Really? Ok, interesting. Many pages ago people were advocating its use, saying how great their aircraft tracked down the runway. When did the thinking on that change?

And, why do you say it is doing exactly what it is supposed to? I’m curious as to why it is doing it only while the engine is running.

Kurt

redball8

My Feedback: (128)

Gotta use the gyro in rate mode, not heading mode. Works a treat, once you get the gain tuned properly.

BarracudaHockey

My Feedback: (11)

The word you're looking for is procession

In other words the gyro sensor is picking up vibration from the airframe.

TEBerg

My Feedback: (1)

You are experiencing 'creep' in heading hold mode.

This used to happen with older gyros when the temperature changed. You would/could use sub-trim to counter the creep.

The 401 recommends that all sub-trim and trim adjustments are zero and that you mechanically center your rudder. Because, the trim changes will cause the creep.

With your problem; it seems as though the gyro is "hearing" noise when the engine is running and it is causing the creep. We would occasionally see this on helicopters and would have to go ground the frame to solve the problem..

So, you may have to look at your options for masking the noise. You may need to shield the gyro signal wire, provide some noise suppression such as a magnet ring (choke), etc.

You can set up a heading hold just fine on an airplane.. Feel free to send me a PM with any questions..

Blue Skies

TEBerg

My Feedback: (1)

Good point - did you isolate the gyro with two layers of the gyro tape/foam? It could just be the vibration. I used to see that cause procession in either/both directions though..

BarracudaHockey

My Feedback: (11)

I recommend against using heading hold on a fixed wing with that gyro. Most people don't know how to cope with it.

It's great if you just want to take off straight and turn it off but if you touch the stick as most of us do out of habit, it will turn until you correct. It's a weird sensation. The iGyro has a hold mode that releases and reverts to rate as soon as you move an axis off center and it's disabled on the rudder axis, there's a reason for this.

Even the Demon instructions tell you to use hold only for trying to hover or torque roll.

Don't take it to PMs, throw it on out here, I love a good technical discussion

TEBerg

My Feedback: (1)

I'm ok leaving it on here.. I just didn't want to promote other products in the discussion.

As it happens, I just ordered an IGyro 1e to put in a warbird. I can only have rudder gyro in competition.

I have been messing with a 401 knock-off, but found out the HH mode is Super sensitive because it changes the Rate at which the yaw changes, not the angle the yaw changes. I had to make the center stick movements almost dead to keep from over-controlling the turn.

This is because with a heli, when you yaw the tail you are asking it to 'spin' and not just to change direction. Changing the rudder ATV can slow the spin, but the gyro is still super sensitive.

Now, if you ALWAYS fly the rudder stick using coordinated turns; then the HH won't be an issue. It's becomes an issue for those who bank and yank without remembering there is a left stick. (unless you hold the turn too long and the HH keeps turning the tail)

However, I'm planning to use heading hold for the take off run and probably taxi back after landing. Then I'll have rate mode to dampen any 'wag' during normal filght.

I'm going to try the 1e for the reason stated - it overrides HH mode as soon as you move the stick and you have regular rudder control.

But, this is a bit beyond the creep or procession issue stated.. That needs to be solved before you should even taxi test..

For example; I had originally purchased the E-Flite G110 and the instructions said, when it starts to drift (as can occur during flight) adjust the transmitter subtrim.. That gyro didn't make it to the taxi testing..

KurtS

Ok, interesting stuff, thanks. I'll double check the sub trim and see where it might be set.

As for the mounting, no, I'm probably using the wrong stuff. It's double sided 3M tape, probably 1/16" thick. Could very well be my issue right there, too thin, too hard, too much airframe vibration being transmitted into the gyro. Is there another type of foam tape I could buy at HD or Lowes?

I will say that today was the first day flying this airplane with a gyro. In rate mode it was rock solid and very smooth, just as I thought it would be. HH would be nice, but I would flip the switch to rate mode before touching the rudder. At least in my head now I say that's what I would do. If I cant use HH it isn't the end of the world, I did notice a nice, easy, smooth and basically straight takeoff each time, albeit with the addition of some right rudder.

I have the same gyro in another airplane and rate mode works great. I haven't tried it yet in HH because I had been unaware I had to have the transmitter in HH when the receiver was powered up. Now that I know that, thanks to this thread, I hope to try it tomorrow.

Kurt

johnboy151a

My Feedback: (68)

I forgot all about this thread, glad to see it's still active. My needs are all about the rudder. I have an old biplane Warbird that's nearly impossible to keep from ground looping during take off. I really don't need an entire flight stabilization system, just something to hold the rudder during take off and then cam be turned off. Suggestions? Learn to be a better pilot?
John

jescardin

My Feedback: (1)

On Futaba airplane gyros HH was intended when the pilot just didnīt like to bother with that particular function! If you are unable of keeping touching the control for that function you JUST not should use HH but rate mode.

I discovered this many years ago and, in fact, not with a Futaba gyro but with an English one that I think was the first one offered for airplane use which included HH. As development test for an UAV Spanish firm I installed it on a Great Planes PT-40 trainer aiding aileron control and went flying. As first I tried classic rate mode and I was very, very satisfied with the recovery and self stabilisation from the gyro, although it required a totally new flying procedure of keeping pushing the stick during the complete turn or, if you relaxed, the plane levelled and it took an eternity to finish a complete circle.

After some time to get accustomed on rate mode I put the plane straight and level and switched to HH. First I was amused about how perfectly straight the plane tracked but when it went quite far away and I tried turning...... it flick rolled 2 turns, first to right and then to left when I instinctively corrected. I saved the plane leaving the gyro to stabilise the plane and switching to mode OFF. I repeated the test 4 or 5 times safely high and I confirmed that leaving the gyro on HH mode alone it flew the plane perfectly, but it was totally incompatible with manual control!

Regarding GY401 "creeping" it is not temperature related, just it was how it worked and it is best to go for zero trim and make a central calibration so the gyro learns the exact control zero position. Anyway, both with engine off and started you may notice a very little and slow "creep" but this will be compensated by the gyro when moving as the "creep" will tend to deviate the plane and the gyro will automatically compensate for this.

Anyway and as other forum friends have explained for general use the rate mode is more than enough and you can switch to HH just for a knife edge pass, but ALWAYS remembering no to just touch the rudder stick!

BarracudaHockey

My Feedback: (11)

Igyro single axis works great for that
https://powerbox-americas.com/collec...werbox-igyro1e

BarracudaHockey

My Feedback: (11)

The 401 isn't sensitive to sub trim like some of the newer gyro's are like the Demon.

The 401 during initialization (the flashing phase after power up) learns what the center pulse is on the rudder channel, its important not to touch the rudder or model during this process which takes about 5 seconds.

johnboy151a

My Feedback: (68)

Anyone use the Futaba GYA 440 gyro for rudder control? I mainly need one for take off. I do not have a system that it set up for s-buss.