Throttle Curves 0...+100 vs. -100...0...+100

Hi all,

has this question been placed and answered already?

I am looking for the definition of the scaling, either if I want to have 0..100 or -100..0..+100.
Currently scaling is fixed for the direct servo output to the latter either in simple or advanced GUI mode.

In the simple GUI mode gyro gain can be setup from 0..100 range and is automatically setup correctly by re-calulating the values in advanced mixer to -100..0..+100 (you can copy a #1 simple model to a #2 advanced mode and see what has been setup).


BTW: I am coming from a Spektrum DX8.
Airware has 5 throttle points: from 0 to +100. Not -100 to +100.

I am setting up a Walkera V120D02s heli with BLHeli governor, so these 3 flight-modes may be reasonable:
- 65%
- 75%
- 85%

I am playing around with the individual throttle values and gyro gains in N/Fmode 0 normal mode, so no absolute fixed curve in N/F0.

When I know that the speed controller has max of 100%, it makes sense to set it to max of 85% (from 100) throttle. I can setup this 1:1.
Same applies to Blade 4503D: Manual tells to set throttle max of 72,5%.


How does this work in DeviationTX?
Either if I am in the simple or advanced GUI mode, a curve starts at -100 to 0, not 0..50..100.
Probably for a fixed throttle it may be more elegant to use a different curve setting, not a normal point curve.

Does it make really sense to have to setup a quite different curve in the scale of -100..0..100?

Same applies to a Parkzone StrykerQ which should not start with +100 but lower where I really would like to setup a curve, not a fixed point value.


It got to my attention that I have to re-calculate all throttle curve values:

It is wrong to set the throttle endpoint to 85%, but instead it has to be 70%!?!


Question: Is there any trick for the DeviationTX curve window to be able to setup 0..100 throttle values instead of -100..0..+100?

Even the simple GUI requires to setup the re-calculated -100..0..+100 throttle values
My V120D02s model is already setup and working with the advanced mixer gui.


So far I like the power of DeviationTX and just can laugh of the limited older Airware firmware!

Greetings from Germany

Thomas

Already changed "Curve type" for StuntMode 1/2 from "Point" to "Fixed" (governor). So only N normal mode has a point curve to play around with throttle and gyro gains.

You can simple recalculate.
+100 formula is for converting back to 0 to 100 scale.
So if you had 80 on your throttle curve in deviation, using the +100 ÷ 2 and you get 90 which is correct.

Either way works.

(0 to 100) to (-100 to +100):

[(0 to 100 value)-50] x 2
or
[(0 to 100 value) x 2) -100

To to back to 0 to 100:

[(-100 to +100 value) ÷ 2] + 50
or
[(-100 to +100 value) +100] ÷ 2

Thanks Joshua,

your formulas help.


But it is still pain to have to do that when programming a fixed or point curve where the "real values" are different on the speed controller.
Of course the channel monitor will show the -100..+100 (servo) throttle.

I do not really like it that the main screen shows (CH1 DSMx) not the real speed controller 65/75/85% throttle values but the fake channel values


Where is the benefit to have to re-calculate the throttle / gain values myself and maybe even struggle setting up the 5-9 mid points for "unreal" servo channel values?

Checked Futaba T10, it uses like a DX8 0..+100 throttle values.
Futaba T14SG - I can not even download the manual. HAHA!
Jeti DC14/16/DS seem to use - like DeviationTX - for function curves -100..0..+100 programming values (picture page 90). 1.300EUR and then I have to do the math all by myself?


For a heli and gyro gains it is not that important to have a 0..100 setting.


Simple GUI throttle point setup / mid points:
I also do quite like the simple GUI throttle point setup.
Is has automatically changing 9-13 sub point suggestions when using low/high/mid value...but lacks 0..+100 setup config and does NOT show a simple option to temporarily disable mid point sub changes (manual mode).

For the advanced GUI (complex mixer) you seem to have to setup all 9/13 points all by yourself manually, even for the 1st setup. No suggestions for mid points at all.

Coming from the programmer side I do understand that changing / improving the advanced GUI complex mixer curve and merging some extensions for the simple GUI throttle curve definitely will not be a too easy job.
So I do not expect further improvements that soon


How difficult would it in the C source to add a window 0..+100 scale option for a complex mixer with a background math which sets the servo throttle value but displays 0..+100 values in the curve screens?

What is the easiest way to extend the complex mixer curves and merge some (display/math) code of the simple GUI throttle curve? Probably both codes are a "no fit"?


For my StrykerQ with setting up ~70-85% throttle for hand start (FM0) I also did the throttle programming wrong, setting too high servo values

Regards

Thomas

Hi Fdr,

Yes I know. Different supported protocols, different throttle channels.


Maybe by introducing a new Curve "Throttle 5/9/13-Point" or "Throttle-Fixed" type?
Then it's generic and settable on any channel / complex mixer.


As I noticed the throttle curve is displayed in the complex mixer screen on the right side even you do not select the sub-menu 5-point-curve / 9-point-curve (for editing).
So the rendering would be different even in the main complex mixer screen - but I would not care too much about the correct display at this screen either.


I am just somehow missing the field "range-type" below the "scale" in the complex mixer window?


But the complex mixer is of course missing the "mapping layer" in between edited curve/fixed values and the servo channel output values in between.


Not worth the effort?

Here is a link to a current Spektrum vs Futaba discussion: www.helifreak.com/showpost.php?p=7148802&postcount=160 (and following posts).

Has anyone of you maybe finished for "throttle" a mixer with input from a virtual channel which does the above math to translate from 0...100 to CH1/3 THR -100...0...+100 automatically?

The virtual channel mixer curve would have to be set for the curve or fixed to 0...100 instead of -100...+100, just like Spektrum Airware or the Standard GUI mixer allows.
The complex mixer(s) on the THR channel should use the input and convert it for the required signal.

Not really needed for 1:1 throttle stick curves, e.g gliders, warbirds, etc., but would be interesting to be used for helis and fixed/custom throttle curves.

How can the -50 x 2 or x2 - 100 be computed with 1-n complex mixers including virtual channels?

Yes sorry, I am either too lazy, have not really THAT time.....or both: I have to admit that I tested nothing until now
Maybe winter...

Just some ideas / brainstorming...

Thomas

Not sure exactly what you are asking. But for some of my planes I setup a virtual channel with the throttle as input, scaled 50%, then offset +50, so on the main screen I have a big box reading 0 - 100%, rather than -100% to 100%