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Old Jul 16, 2015, 06:30 AM
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The gyro is in normal mode at all times as it did not hook it up to the extra channel to make selectable. We tried the 3d mode in another light foam prop plane and I wasn't impressed. The regular mode is great for the scale jets at all times. During the knife edge I am holding full rudder ( with travel reduced to to prevent a climb) and the gyro does a great job keeping the path straight. Usually a fair bit of aileron and some elevator would have been held as well without the gyro.
On approach the pilot still has to hold some elevator as the gyro will allow the nose to drop when speed decays. The gyro just keeps the plane from being rocked around in turbulence. The plane only does what I want it to do. Very nice when doing extreme low level turns too as the bank angle I set doesn't get bumped too far by turbulence.
The technology works. It is like flying in calm conditions at all times.
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Old Jul 16, 2015, 07:48 AM
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Originally Posted by PeterVRC View Post
I would say 3D (AVCS) mode for sure......
'Normal' mode is of no real use for that (Knife Edge).

The A3super2 is better.... flight mode control and GAIN also. You even get a Hover mode. Oh, and 2D mode [angle control mode] which allows AoA 'perfection'... good for take-offs and landings.
eg You can dial in a mix to set "Up Pitch X" and just select that on roll-out and the stabiliser will make the plane get to 'X' (say 10deg) and maintain that.... all the way from the ground speed that is possible to achieve, through lift off and climb. (same for landings)
Pretty much to replicate how 4stripes (without that option) did that take-off and landing anyway! Except it can be automated to 'perfection' (stabiliser) and all you use is POWER to control the rotation and extended high AoA gradual climb.
The A3super2 is still quite cheap anyway ($40).
Sounds like a dream. All the gyros that I have tried cannot make me fly like 4Stripes does. Maybe, I need to learn how to dial in.

Cheers,

feda
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Old Jul 16, 2015, 09:20 AM
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Originally Posted by feda View Post
Sounds like a dream. All the gyros that I have tried cannot make me fly like 4Stripes does. Maybe, I need to learn how to dial in.

Cheers,

feda
LOL Me too. I have managed to get pretty good results with a careful setup of gain.


PS. Feda, I have sent you an email re J-10.
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Old Jul 16, 2015, 09:24 AM
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I don't use mine for 3D anyway - I can do better than it can. The coding they have has 'costs' in other responses, so a human can still do better - if they are skilled enough. But if you cannot Knife Edge, then a stabiliser will at least allow you to!

But the 2D mode - changing your control to Angle mode - is very useful for setting 'automated' processes, because all you do is 'set and forget' and the stabiliser takes care of getting it right. But of course ONLY if the aerodynamics still allow it. eg not stalled etc.
You 'request' 10deg Pitch and you get that no matter what. But you do have to control the Power (Thrust) so as not to go fast and climb (unless that is what you wanted)... so you are just using Throttle to form the path - incline, decline, level flight etc - but the stabiliser is setting the attitude that you requested,

Many planes (most) are too hard to Rotate 'slowly' for a scale take-off.... the instant they get some AoA the 'leap' and a human cannot respond in time to stop that. But a 'rocket fast' stabiliser can!

To see some of those in action, watch some real full scale videos of modern fighters. Especially the Su-35 and Mig-29 (YouTube)... F-22 also... you will see their 'Elevators' FLUTTER with huge swings, quite fast, as they land especially. That is the computer (stabiliser... Fly By Wire)... doing what is required to maintain the perfect landing attitude. The pilot just holds "10 deg" stick and the FBW computer does whatever it needs to, to make sure it flies at the 10deg. In many of their cases it also controls the Power (Thrust) to form the complete process wanted.
Models do much the same.... so on a take-off run the stabiliser will set max Elevator from the roll out start, trying to make the Aircraft Pitch up to the Angle you are requesting, but it will 'correct' the apparent excess Elevator use in milli-seconds as speed rises and Elevator Authority increases - and/or take-off leap TRIES to happen.
The Full Scale have much more sophisticated programming, so for eg they do more checks of the situation and will leave the Elevator Neutral UNTIL the 'program' sees the airspeed sensors showing it is near Rotation speed. Even if the pilot held +10deg from the stand-still, it will not attempt to do that until the airspeed is higher. Whilst our cheap stabilisers don't have airspeed, nor detailed coding to do better. But they are still adequate for what we need.
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Old Jul 16, 2015, 06:14 PM
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Most models that do not rotate well or easily is usually due to the fact that the main gear is too far behind the CG. Poor execution by the designers, and lack of testing have many popular designs tormenting their customers.
Thankfully foam models are simple to modify and make things right. Naturally jets fly best off a smooth surface and flying off grass will only make a poor handling model worse.
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Old Jul 16, 2015, 07:12 PM
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The FlyFly Mig-29 is one of the only FlyFly's that they altered the landing gear positions from scale so that the main gear IS the useful "15deg rearwards of CofG". They even had to make the gear retract in the wrong direction (nose and mains) to do that.

Your Mirage is obviously pretty well perfect LG position, to allow the 'on wheels Rotation' !
But if you use that on grass it will bounce along up off the nose on every small 'bump' and almost surely force an early rotation... too soon. Which at the initial lower speeds even full down Elevator cannot prevent.
But you want it set up for a 'proper' runway, and hopefully to be used there... a hard one!
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Old Jul 16, 2015, 07:44 PM
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Here is a quickly thrown together string of FBW examples. (FBW... basically the same as a Flight Stabiliser in 2D/Angle mode of control).

Watch for the 'erratic fluttering' of the Elevators which highlight the motions of the FBW correcting the aircraft's motions to be what the pilot 'requests' via 'stable' flight stick movements. He can just hold "20deg" Up Stick and do nothing else, and the FBW does everything required to assure the plane DOES fly in stable like that.
We can do the same, with a 'Angle Mode' Flight Controller (many names for that, like 2D, Self Leveling, Self balance). EagleTree Guardian, HobbyEagle A3super(1 & 2).
To do that task properly it must have Accelerometers, though JUST gyros (Like the BlueLight stabiliser) can do it via programming but will have 'errors' because without Accelerometers you can never TRULY know the Flight Controller attitude in 3D space.

This is a problem with Gyro only stabilisers that offer 3D/Heading Lock also. They can only measure what the plane DID, to veer off attitude, and then they 'reverse' that with an equal value. They do not use Accelerometers to KNOW 100% for sure what is going on. The shortfall is that when a plane 'deviates' a gyro only measures a RATE of motion change. When you reverse that value, which is technically 'right' to correct it, it does not ALSO account for the effects of 'air' around the plane.
For eg, the 'air' is a 'sea'... with motions exactly as per the seas! If not even more so. Unless it is a dead calm day (and the same for a dead calm see, somewhat), there are always currents, flows, disturbances in the air. When the plane is deviated due to this, a gyro measures that rate of change and for how long, then the Flight Controller 'maths' produces the reverse (inverse) of that and drives the plane back that amount. BUT because the air is incessantly changing, there are infinite error sources to the resultant. The gyro sends the plane back the same Rate and Time, but the air might be moving some different way now so the plane will not end up back where it was originally. A bit hard to explain, but maybe you get the principle(?). A gyro ALONE can NEVER get things totally right. But Accelerators KNOW the precise world X,Y,Z axis at all times... so they know where the plane 'was' and can drive it right back to that exact point again.
For "$10 more" you want Flight Stabilisers with Accelerometers! Which also allow that "Angle mode" of control - if you WANT to use that - and which then allow effective FBW piloting and the functions/processes that adds.

Apart from the ability to set a 'guaranteed' take-off Rotation angle, which the Flight Controller will complete the whole process for you, and the same for landing at a chosen AoA, they offer a very useful Hand-Launch aircraft assistance. You can set a pre-locked in aircraft attitude and when you throw the plane the Flight Controller will control the plane to DO that - as long as the plane can 'fly' and thus has control surfaces working effectively. (A pilot could not make a plane fly if they are not effective either anyway!). But a big bonus of this ability is that you can launch a plane with NO TX used... just throttle up, put the TX on the ground, throw the plane two handed 'properly' (easier then) and the Flight Controller will fly it off at the attitude you set... until you get the TX and begin controlling it yourself again (sending the Flight controller new Requests, or turning it off etc).

....
Fly-By-Wire Elevators (3 min 43 sec)
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Old Jul 18, 2015, 01:19 PM
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I guess I'll also put in a gyro

Flew my Wemo Evo Mirage for the first time in some wind, and it was pretty hard for me to keep the lines - I am sure this is made worse in my case by the throws which I have now at 50% with lots of EXPO, not only because the elevons are huge, but because I left the servos in the stock location but moved the linkages to the top of the wing, and have to use the outer holes on the servo arms.

This is a super light 90mm setup, the whole fan unit (230g total: Evo rotor sans spinner, Haoye FlyFly shroud, 140g Turnigy 3553 1800kV motor), and the Blue Series ESC is the lightest 60A that I know, plus it's flat.
Lipos 5s 3300mA Zippy Compact.
I now made some sort of thrust tube out of Depron because there was an ugly step in the exhaust duct, and I wanted to reduce the outlet diameter a bit.
The sound is not great due to imperfect balancing, but also because I realised too late that I mounted the fan a bit too far aft, not directly at the conical foam section in front of the fan which acts like an inlet trumpet.

Mirage FlyFly 90mm Wemo Evo 1800kV 5s windy (2 min 26 sec)
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Old Aug 07, 2015, 02:11 PM
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Quote:
Originally Posted by mopetista View Post
Flew my Wemo Evo Mirage for the first time in some wind, and it was pretty hard for me to keep the lines - I am sure this is made worse in my case by the throws which I have now at 50% with lots of EXPO, not only because the elevons are huge, but because I left the servos in the stock location but moved the linkages to the top of the wing, and have to use the outer holes on the servo arms.

This is a super light 90mm setup, the whole fan unit (230g total: Evo rotor sans spinner, Haoye FlyFly shroud, 140g Turnigy 3553 1800kV motor), and the Blue Series ESC is the lightest 60A that I know, plus it's flat.
... ..

The sound is not great due to imperfect balancing, but also because I realised too late that I mounted the fan a bit too far aft, not directly at the conical foam section in front of the fan which acts like an inlet trumpet.
.. ...
The bird appears flying well. Thanks for the video, I enjoyed it.

feda
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