How do you connect Gyro into a two servo elevon set-up ?

latrc · Post by **latrc** » Thu Mar 15, 2012 7:23 am

OK ... I have a stock FlySky Vers 2, with FrSky module / Rx.

Plane has split servos for elevons, 1 into aileron Ch 1, other into Elevator Ch 2.

I want to connect a Gyro so I can reduce the torque roll problems on a HK Parkjet when launching.

How do you connect a single servo lead Gyro into a twin servo set-up ? The gyro sense lead I know is not a problem as that goes to aux ch. as I already do on my 450 Heli.

Post by **Crucial** » Thu Mar 15, 2012 9:26 am

Some interesting discussion about this. The guy in the thread uses 2 gyros on an angle to get them both responding to pitch and roll. http://www.rcpowers.com/forum/showthrea ... mixer-unit

I've heard of some people using one gyro to control roll on one of the elevons. Moving one of the surfaces to control the roll was enough.

latrc · Post by **latrc** » Thu Mar 15, 2012 11:02 am

I read the thread ... was really about the Stryker but had a lot of relevance for others wanting to go a gyro route.

The Parkjet is small and 2 gyros would be hard to accomodate. Even 1 is pushing the space a bit. I don't need pitch covered, just the tremendous torque roll at launch.

One suggestion was to switch of Tx elevon mixing ... install gyro to the aileron servo connection, then have V tail mixer do the job. I can see this working as then the mix is AFTER the gyro and hopefully both elevons will then be operated by gyro. One guy reckoned that remixing by Tx after that - but I cannot agree. hy mix before gyro and then mix again ?

I will be experimenting and will report back once I get a solution.

Post by **Kilrah** » Thu Mar 15, 2012 4:11 pm

With only 1 gyro, the V-tail module in the plane after the gyro is the only solution. Disable mixing in the TX of course.

latrc · Post by **latrc** » Thu Mar 15, 2012 5:05 pm

It certainly seems to be the simplest and lightest / smallest solution.

Post by **Crucial** » Thu Mar 15, 2012 5:49 pm

The only complaint I have seen with that solution i that the v-tail mixer isn't smooth enough for some people. I'm curious to hear how your's turns out and if you notice the same issue.

Post by **Kilrah** » Thu Mar 15, 2012 7:18 pm

True that, I don't have first hand experience but I have a good friend who was getting crazy after having had to go through 4-5 different V-tail mixers to find one with decent resolution... Some were really terrible, with maybe only 16 steps over the servos' entire throws (I witnessed that one)... some engineers should be shot

pmackenzie · Post by **pmackenzie** » Fri Mar 16, 2012 2:25 am

There are tiny gyros out there now, nearly as small and light as a V tail mixer would be.
E-tech G104 comes to mind
http://www.ebay.com/itm/F00096-G104-Sma ... 3f08c2dab1
Or perhaps the HK GA250.
http://www.hobbyking.com/hobbyking/stor ... Gyro_.html

Futaba used to make an "aircraft" gyro that would handle dual ailerons (GY351), but it seems to be discontinued.

latrc · Post by **latrc** » Sat Mar 17, 2012 5:53 am

The GY351 is still listed by some vendors but at over $200 ?? There are a number of multi axis / multi input gyros out there at under $20.

I believe Eagle tree have a stabilise system as well .. primarily for camera planes and FPV ... but may be suitable.

My thoughts are that a system aimed at the fixed wing is needed as so far most are helicopter 3D gyros and some of those are not happy in a different axis than yaw. It also needs a factory to realise that a lot of fixed wing today are twin servo set-ups / elevons etc. and not single input / output.

Maybe a combined Gyro / mixer ... ? reducing size and weight.

Post by **jhsa** » Sat Mar 17, 2012 10:25 am

I'm not sure but I think that multiwii has also the option for a flying wing..

latrc · Post by **latrc** » Sat Mar 17, 2012 12:50 pm

jhsa wrote:I'm not sure but I think that multiwii has also the option for a flying wing..

Sorry ??? you lost me there ........

Post by **jhsa** » Sat Mar 17, 2012 1:06 pm

sorry, I should have explained better. Multiwii is the code, normally for multirotors and uses sensors like the wii motion plus and nunchunk (most common) among others, connected to a microcontroller like the arduino pro mini for example.. And I think that the latest versions of the code has support for a flying wing that uses elevons. At least I think someone used it for a stable wing platform.. please look here.
WARNING: It's a huge thread

http://www.rcgroups.com/forums/showthread.php?t=1261382

latrc · Post by **latrc** » Wed Mar 21, 2012 8:41 pm

I'm a simple soul and to be honest that is outside of what I want to get involved in ... a simple plug and play is more suited to me !!

But cheers anyway !

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