Regarding the VT, is it beter to use à gyro wen flying whit VT? Is it flying bether?
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Originally posted by Edwin-0 View PostRegarding the VT, is it beter to use à gyro wen flying whit VT? Is it flying bether?
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Originally posted by Edwin-0 View PostRegarding the VT, is it beter to use à gyro wen flying whit VT? Is it flying bether?
VT does not really add to the need though - if you have a non-VT model that is tuned properly and not overly sensitive, it will not become harder to fly once you add VT. VT has a pretty dormant authority in most parts of the flight envelope. You need low speed, lots of thrust, and lots of input for VT to really kick in and overwrite the aerodynamics.
Freewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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Originally posted by Edwin-0 View PostRegarding the VT, is it beter to use à gyro wen flying whit VT? Is it flying bether?
1. You can have gyro operate on both TV and on elevator/rudder. Depending on your gyro setup, this might not be easy to do. One was is to mechanically tune the TV to use exactly the same signal as the ele/rudder (same trim, same travel...just Y cable the signal). Another way is to have a gyro function that can operate before a mix.
2. You could have the gyro operate on the ele/rudder, but not on the TV.
3. You could turn off gyro when TV is engaged. This might make sense if you engage TV only to do crazy maneuvers that might not play well with a gyro anyway.
Anyway, the point is, there are multiple ways to set this up. Anybody have experience there?
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I have two SebArt Mig 29s. These were the first mass produced "3D" EDFs (made by Freewing for SebArt). One uses one gyro to affect both the control surfaces and the VT nozzles. The other Mig uses two gyros - one for the control surfaces and the other for the VT nozzles. The two Migs are wired slightly differently. Once set up and the gains are optimized, the gyros always stay on, even though I have a switch to turn it OFF. Remember that most gyros stabilize primarily when the sticks are at center. Stick movement supersedes gyro response, hence, the only time the gyro needs to be turned OFF is during the set up and flight testing stage. Gyros are very helpful when hovering and during normal flight, they make maneuvers much more precise and crisp, landings smooth.
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Originally posted by Gringotuerto View PostThis raises a question of how you would set up gyro on a plane with thrust vectoring. Has anybody done this before, and if so, how?
[...] Anyway, the point is, there are multiple ways to set this up. Anybody have experience there?
Originally posted by Gringotuerto View Post1. You can have gyro operate on both TV and on elevator/rudder. Depending on your gyro setup, this might not be easy to do. One was is to mechanically tune the TV to use exactly the same signal as the ele/rudder (same trim, same travel...just Y cable the signal). Another way is to have a gyro function that can operate before a mix.
1- This means you can't trim them independently, which is very important for TV jets in my opinion.
2- You will have to apply same gain to VT nozzles and control surfaces which, is far from ideal. You usually want high gain on nozzles and lower gain on control surfaces, and the gain distributes different over the axis for one and the other, so better add two gyros. (Or use one gyro just for nozzles or just for tailerons + rudders).
Originally posted by Gringotuerto View Post2. You could have the gyro operate on the ele/rudder, but not on the TV.
Originally posted by Gringotuerto View Post3. You could turn off gyro when TV is engaged. This might make sense if you engage TV only to do crazy maneuvers that might not play well with a gyro anyway.
You didn't list what for me would be the most obvious option that I'd go to by default.
That is, gyro only on the vectoring nozzles.
It's the easier to do as you can detach nozzle control from transmitter trim (so that adjusting trims won't mess up neither your thrustline nor your center-points for the gyro), will mostly feel like it's not there during normal flight as the dynamics of the stabs take over the nozzles but you will notice the jet is much, MUCH easier to control when slowing down, doing high alpha and performing post-stall stunts. Recovery from bad scenarios is much easier too. Of course, you need a bit of throttle so that the nozzles act, if you cut throttle, the plane will fly as if the gyro were off.
Finally, if you really want the extra benefits of both conventional aerodynamic surfaces and vectoring nozzles all stabilized, you can either install two separate 3 axis gyros, or get a high-end gyro that will offer enough separate stabilized outputs to make all channels stabilized.
Here's some footage of my Su-35 and Eurofighter flying with gyro only on the nozzles (EF does have a separate gyro on the canards for a different -scale- reason though):
Hope that helps! :)
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Originally posted by Airguardian View Post
You didn't list what for me would be the most obvious option that I'd go to by default.
That is, gyro only on the vectoring nozzles.
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I do have a switch to kill the gyro yes. I maiden my jets unstabilized and get them dialed out as best as I can before engaging the gyro. Once the gyro is proven and works as I intend to, I leave it always on. Will usually power the jet with gyro off, set the plane on the runway and toggle it on just before take-off and killing it off afterwards. Also if for any reason gyro is not working correctly, you can just switch it off. ;)
A single gyro switching from one set of surfaces to another? That's weird and would require quite some custom programming (say arduino board or something like that), I don't see the point.
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So yea... I succumbed to the peer pressure... I'm waiting on the boat to come in now too.... also ordered a set of the centerburners from Chris aka theRCGeek!The new MiniBurner from the RC Geek. Full demo showing how good these burners look in daylight clear into the evening in the gorgeous Spring skies over Utah....
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Originally posted by Gringotuerto View Post
This raises a question of how you would set up gyro on a plane with thrust vectoring. Has anybody done this before, and if so, how? Here some options I can think of, and there are probably others:
1. You can have gyro operate on both TV and on elevator/rudder. Depending on your gyro setup, this might not be easy to do. One was is to mechanically tune the TV to use exactly the same signal as the ele/rudder (same trim, same travel...just Y cable the signal). Another way is to have a gyro function that can operate before a mix.
2. You could have the gyro operate on the ele/rudder, but not on the TV.
3. You could turn off gyro when TV is engaged. This might make sense if you engage TV only to do crazy maneuvers that might not play well with a gyro anyway.
Anyway, the point is, there are multiple ways to set this up. Anybody have experience there?
I prefer having gyro on everything, but that clearly puts fairly high requirements as to which gyro(s) to choose.
For my part, I have used a jeti assist receiver with up to 12 stabilized channels on my eurofighter. 6 stabilized channels for pitch (canards, elevons, both nozzles), 4 channels for roll (elevons and nozzles), and 3 for yaw (rudder, wheel and nozzle yaw). 11 total (yes, 6+4+3 = 11 because of overlap)
For the MiG I will be using two jeti satellite receivers through a Cortex Pro in serial mode, into a Jeti CB200. Will provide 15 stabilized channels with the best gyro in the world.
As Alejandro said, any sort of Y-connection between VT and control surfaces is something I would highly advise against, since it makes it impossible to tune your thrust line and trim surfaces independently - and that is a must, simple as that.Freewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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Originally posted by Alpha View Post...I'm comfortable showing a bit more "Behind The Scenes" of an Upgrade Option for the MiG-29 which is *NOT INCLUDED IN THE PNP*, but instead is *Sold Separately*. We'll publish pricing, model photos and video, and installation instructions over the coming 3-4 weeks, as we tidy those details...
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Originally posted by Gringotuerto View Post
So it seems like MotionRC is going to both release STL files, but also sell the part? I wonder what material will be used for the "store-bought" version, and if PLA would be strong enough for this. It seems large ABS parts often suffer from a bit of warping. And if PLA is infused with strengthening material (like carbon fiber), it then requires a hardened nozzle (or wears out the nozzle).
PLA may very well have the required strength if careful with layer orientation. My main concern would be that any sort of large, sliding contact surface similar to the old nozzles would be very difficult to achieve with FDM printingFreewing A-10 turbine conversion: http://fb.me/FreewingA10TurbineConversion
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