Mixing question for gliders

[rcgyuk]

Hi,

I am learning open9x and am setting up mixes for my electric sailplane.

The scenario I am imagining is this.

In normal flight, full right aileron on TX will result in small amount of left aileron down, and large amount of right aileron up, due to differential.

Now consider the glider descending to land, with full butterfly mix deployed.

All 4 wing servos will be at limits, inboard flaps full down, and outboard ailerons full up.

Now consider sending a small amount of right aileron from the TX.

Only servo that can move is left outboard aileron can move a small amount down. This will not give a positive command response (I think)

What I want to achieve is that in this situation, the right inboard flap moves up, proportional to the amount of butterfly mix deployed, to assist the left aileron. Left flap and right aileron would remain at limits and not move.

so full butterfly mix and full right aileron would move right flap from full down to full up, with the movement of this surface being less if either / or mix or aileron is less than full. (not that I can imaging sending full right aileron when descending under full butterfly mix and 10 feet off the ground)

Or maybe there is a better way way?

[Rob Thomson]

Right....

If I understand correctly, then issue is that when you have xrow deployed, it is difficult to get aileron response. Especially when differential.

What you actually require is variable differential. So when in the flight mode for Crow, the differential is reduced in proportion to the amount of Crow deployed.

Is that why you mean?

Next question is important. Do you have the gvar support enabled in open9x?

In have done the same thing before, using gvars and a custom switch. Essentially you can vary then differential dynamically in response to the amount of crow applied.

Rob



Sent from my GT-I9300 using Tapatalk 2

[rcgyuk]

Hi,

Yes I have Gvar enabled.

Variable differential will give me more down on the left aileron, but I want an additional variable response to the right inboard flap as well. So, no crow = no movement of flap(s) with aileron (at least in landing phase), 10% crow and full right aileron would deflect right flap from -100 to -80, 50% crow and full right aileron = -100 to 0 and 100% crow and full right aileron = -100 to +100. Smaller amounts of right aileron would produce a % of this movement.

[ReSt]

I have a similar situation and recognized that behavior. My solution in flight was to temporarily reduce crow (controlled by throttle stick) to get the aileron response.

I found the following solution, that I have not yet tested in flight.

For the landing phase (crow) the function of the throttle stick is splitted.
I control crow with the lower half (0 to -100) of throttle stick while the upper third can run the motor from min to max via a curve.
For landing phase I reduced the weight of throttle that controlls the aileron to 80% so that the aileron does not go fully up.
Then I add a mix with a high channel (e.g. ch16) with 100%

Ch04 .... there are other mixes
80% Thr Phase(Break) Curve(Curve<0)
+100% Ch16 Phase(Break)

CH16 +80% Thr Phase(Break) curve<0
* 100%Ail Phase(Break)

This multiply mix adds an amount of aileron to the aileron that depends on the position of the throttle. The more throttle (=crow) the more aileron.

with full crow, both ailerons will go up 80%
With additional max aileron right, the right aileron goes up to 100% and the left aileron goes down to -80%
(without the multiply mix, left aileron would go down to +20%)


Reinhard

[Rob Thomson]

Hi,

Yes I have Gvar enabled.

Variable differential will give me more down on the left aileron, but I want an additional variable response to the right inboard flap as well. So, no crow = no movement of flap(s) with aileron (at least in landing phase), 10% crow and full right aileron would deflect right flap from -100 to -80, 50% crow and full right aileron = -100 to 0 and 100% crow and full right aileron = -100 to +100. Smaller amounts of right aileron would produce a % of this movement.

So why not use a second gvar with an adjust gv function, and a smaller mix input for the flaps?

Rob

[rcgyuk]

Let me check my understanding of global variables. You would use them to vary a mix in flight, to find an ideal value, i.e. how much down elevator to mix into throttle, for example, but when you have found the ideal amount, you would would replace the Gvar in your mixes that you found experimentally in the air with the actual %

I can imagine their being more than 5 things I want to set up in flight.....

[Rob Thomson]

Or... You can use them to dynamically set say... Expo based on throttle position.

Or differential based on Crow applied.

Etc..

Sent from my GT-I9300 using Tapatalk 2

[rcgyuk]

Now I just need to set up the flight phases. I can only think of 3, launch, under electric power, Glide, with variable camber on the throttle stick and no power, and land, with the throttle stick split between crow and power.

Anyone suggest any others?

[Rob Thomson]

If I could suggest a mod that will make your life easier?

Extra 3POS switch

This mod is soo easy to do, and makes setting up gliders a little easier. (soon open9x will support it by allowing you an extra ID3/4/5!)

The way I use it is as follows.

3POS on right hand gives me 3 flight phases
- launch / power (throttle cut also configured on motor switch for safety)
- fly
- land

P3 (no a 3 way switch) give me camber
- reflex
- normal
- float

Doing it like this means that the throttle gets used for only 2 functions.

launch - throttle works as a power stick.
fly - throttle stick inactive allowing me to reposition the stick for landing
land - throttle working in reverse for crow.

I find the 'fly' mode being in the middle is essential to avoid motor stop/starts unexpectedly.

Make sense?

Rob

[rdeanchurch]

If I could suggest a mod that will make your life easier?

[url=viewtopic.php?f=26&t=498]Extra 3POS switch[/
.........
Doing it like this means that the throttle gets used for only 2 functions.

launch - throttle works as a power stick.
fly - throttle stick inactive allowing me to reposition the stick for landing
land - throttle working in reverse for crow.

I find the 'fly' mode being in the middle is essential to avoid motor stop/starts unexpectedly.

Make sense?

Rob

Rob I assume that the Jhas posted schematics is what you are referring to, correct?
Have you posted a eepe/c9 file for one of your gliders setup with this?
If not would you mind doing so or pm it to me?
Please.

[Rob Thomson]

What you want is to do this:



So you remove the POT. Put in a 3POS toggle switch, and wire up the wires from the pot to the switch instead.

It effectively works like a pot saying 'FULL LEFT, MIDDLE, FULL RIGHT'

I can post a config later - out most of the w/end, so please do remind me!

Rob

[jhsa]

Looking at it, I wonder if those resistors values should be increased to something like 4.7K
The pots resistence is 5k all the time between +5V and ground. the switch is different as we short one resistor or the other. in this case leaving only 2.4K between 5V and GND..

[Rob Thomson]

I used 2.7k and worked perfectly Not really too critical as just a toggle output. You then use a curve to adjust the position, or just limits.

rgyuk. Was it a phoenix you where setting up?

[jhsa]

The problem is not working or not.. is that when the switch is toggled to one side only 2,4K will be in parallel with all the pots in the radio decreasing the total resistence and putting more load on the regulator.. maybe the difference is too small or maybe not.. I didn't calculate..

EDIT: well, just did it.. and if I did calculate it well, the difference is 1mA, so not to worry..

[rcgyuk]

The glider is a Simprop Solution XL, 4 meters with 2 servos in each wing.

When I had er9x on the TX, I had it set up very much like the lesson 05 in the tutorial videos. Throttle was set to beep on center.

You launch in, well, launch mode, throttle uses full range of throttle stick. At the top of the climb, you cut throttle to half, confirmed by the beep on center, and switch to glide mode.

You now have full span variable camber on the throttle stick, with an option to turn on pot 3 to control the motor. this function has a warning enabled.

For landing, you set the camber to zero by centering the throttle stick, confirmed by beep on center, and switch 3 position switch to down position.

You now have crow on bottom half of stick and throttle on top third.

My last question is that I can't think of a 4th flight phase I might need, to make it necessary to add a second 3-way switch.

What are the pros and cons of combing a 2-way switch and the 3-way to give me 6 software switches, as opposed to physically adding a second 3-way switch ?

Robert

[ReSt]

I have set up my glider exactly the same way.
As I never flew a glider with aileron before and a lot of other functions I have set up one switch, my so called Simple flight mode where I do nothing else but a simple 4 channel glider. So in case i get everything mixed up I can switch to my simple mode (aileron, rudder, elevator and throttle without any special mixes or functions) and try to get erverything done.
But gladly, never needed it.

Reinhard

[rdeanchurch]

Rob...a reminder to please post an er9x or o9x example. I'm setting up a friends plane. He has a Phoenix 2000 and a super skysurfer. Both have have 4 servo wings. Right now he is running er9x but I'm switching my tx to open9x and have done all the setup of my FB. I could switch him to o9x easily. He still Flies mostly with a DX7 and I do most of the tx setup. I Refused to try to setup with potential for crow and flaperons on a DX7 for either of the above. Like ReSt I plan on a gadget switch....it's a simple 4 channel like plane one way and has the sailplane bling the other.
Thanks

[Rob Thomson]

Sorry for the delay on this.

Family life is keeping me a little busy.

I am intending to completely setup a new glider (a phoenix) with this methodology. I will post the mix as soon as it is done.

Rob

[rdeanchurch]

Appreciate it. No hurry.

[rdeanchurch]

Appreciate it. No hurry.

[rcgyuk]

Here is my set up so far. About 95% complete, still to do the dual rates / expo, timers, vario and telemetry settings

Switches are:

Rudder, safety for engine
Throttle switch on, activate basic mix, cancels all mixes, standard 4 channel powered plane
With throttle switch off,

ID0 = launch, no mixed rudder, down flaps with up elevator, fully proportional power on throttle stick.

At altitude, throttle stick to center (dead band from -10 to +10 set by curve 2, so absolute center not required), confirmed by beep, !ELE and ID1 = glide phase.

Now have variable camber on throttle stick, flaps mapped to ailerons for full wing ailerons, rudder mixed to ailerons.
Elevator mixed into camber to compensate, set at 0% controlled by GV1

Gear switch to on allows GV1 to be altered by throttle trim to precisely set amount of elevator needed to control camber. Gear switch to off will prevent further change in GV1

This can be only found in flight.

Also don't yet know if will need different amounts of elevator mix for camber and reflex. If I do, will have two elevator mixes, <0 and >0, both will be set in flight.

Switch elevator switch from !ELE to ELE, will add proportional throttle on Pot3, warning 1 in this configuration, single beep every few seconds. (phase Pglide)

Switch to ID2 will give landing phase.

No mixed rudder, no flap mix to aileron, -100 to 0 on throttle give crow brake, +20 to +100 give power to motor. (curve 3)

in any phase, throttle switch to on will cancel phase and revert to standard 4 channel plane instantly. All other phases have a 1 second fade in and fade out.

All the various weights in mixes need testing in flight !!!!!

Have really leaned a lot about open9xsetting this up, and have borrowed heavily from other peoples mixes here.

[rdeanchurch]

Rcgyuk

Nicely done. I played with this afternoon and even think I understand most of it.

Thanks

[rcgyuk]

Have now solved another puzzle, using the throttle stick to control the timers, but the throttle stick is not always controlling the motor.

I set channel 16 to source = channel 1 (my motor channel) weight 100%

On screen 2, I set timer 1 to TH% and timer 2 to THt

Then about 4 lines down, I set T-Trace to CH16.

Sorted

[vladoslo]

[quote="ReSt"]I have a similar situation and recognized that behavior. My solution in flight was to temporarily reduce crow (controlled by throttle stick) to get the aileron response.

I found the following solution, that I have not yet tested in flight.

For the landing phase (crow) the function of the throttle stick is splitted.
I control crow with the lower half (0 to -100) of throttle stick while the upper third can run the motor from min to max via a curve.
For landing phase I reduced the weight of throttle that controlls the aileron to 80% so that the aileron does not go fully up.
Then I add a mix with a high channel (e.g. ch16) with 100%

Ch04 .... there are other mixes
80% Thr Phase(Break) Curve(Curve<0)
+100% Ch16 Phase(Break)

CH16 +80% Thr Phase(Break) curve<0
* 100%Ail Phase(Break)

This multiply mix adds an amount of aileron to the aileron that depends on the position of the throttle. The more throttle (=crow) the more aileron.

with full crow, both ailerons will go up 80%
With additional max aileron right, the right aileron goes up to 100% and the left aileron goes down to -80%
(without the multiply mix, left aileron would go down to +20%)

Hello. Have You tested your solution in flight? I use your phoenix.eepe to control my Alpina4001 on slopes, with some modifications. It works like a charm!
Now,I added this:

Ch04 .... there are other mixes
80% Thr x<0
+100% Ch17

CH17 +80% Thr x<0
+100% Ail
It works, but now, when throttle stick is in middle position, aileron control in landing mode is a little bit over sensitive. Also I lost differential in landing mode, with this mix added.
Best regards, Vladimir.

[ReSt]

I'm flying it on a HK Phoenix 2000 and it works very good.

For CH17 change the +100%Ail (add) into a *100%Ail (multiply). That will make the difference.

The plane is under full aileron control even with full crow.

Reinhard

[vladoslo]

I'm flying it on a HK Phoenix 2000 and it works very good.

For CH17 change the +100%Ail (add) into a *100%Ail (multiply). That will make the difference.

The plane is under full aileron control even with full crow.

Reinhard

Thank you very much. Can you share eepe file for your Phoenix 2000?
Vladimir

[ReSt]

My Settings are for a 9x with the m128 processor, so it might use switches (...) that are not available in the m64 version.

I have downloaded the settings from my radios and they should work.
Phoenix2.eepe is from openTx r2.1.6, downloaded with Companion 2.0.17
Phoenix3.eepm and PhoenixNeu.eepm are from ER9x r819, downloaded with eePe r420.

I can load and simulate all of these files and they seem to behave as I'm used to.

I also have put two PDF files into the zip file, one for Opentx and one for ER9x.
They are a little bit outdated, but
1. they describe what the setup is supposed to do and
2. tell you what every mix line is thought for.


Reinhard

Phoenix2000.zip

(102.91 KiB) Downloaded 197 times

[johnrcglider]

Hi, have you got a list of the inputs and outputs in OpenTx ?

I use A T E R - Mode 4 so not sure what I would put in the inputs and outputs screens?

John

[Daedalus66]

Please keep related questions one thread.