FSX Jerky fan animations.

[Osian]

I am trying out my model in FSX and it has the classic jerky/shaky fan animations.
I have seen FSX models with completely smooth fan animations.

Is there a solution for the shaky fan animations ?

Thanks in advance.

 

[F747fly]

I'm not quite sure what you been by "jerky fan" but assuming you want a change from the smooth linear animation, you'd simply have to apply more incoherrant keyframes. So instead of having the ussual 0 frames - 0 degrees, 25 frames - 90 degrees, 50 frames - 180 degrees, 75 frames - 270 degrees, 100 frames - 360 degrees you could for instance vary the frame numbers and/or degrees, this should make it "jerky"

 

[tgibson]

Increase the total number of keyframes in the model and in the modeldef file until it's not jerky anymore. 100 is not enough.

 

[ozzman1997]

I think I know what you're talking about Osian, and this has been frustrating me since day 1 as well. There are some FS9 models that show smoothly rotating fan blades that actually correspond to the N1 speed, but almost every native FSX model appears to have this instantaneous spin-up of engine fans.

This is the XML code for N1_0_still:

<PartInfo>
    <Name>N1_0_still</Name>
    <Copy>prop_anim</Copy>
    <AnimLength>100</AnimLength>
    <Visibility>
      <Parameter>
        <Code>
          (A:ENG N1 RPM:1, percent) 6.25 &lt; if{ 1 } els{ 0 }
        </Code>
      </Parameter>
    </Visibility>
    <Animation>
      <Parameter>
        <Code>
           (A:ENG N1 RPM:1, percent) 0.01 &gt;
           if{ (A:GENERAL ENG RPM:1,degrees per second) (E:ABSOLUTE TIME, second) * 360 % 3.6 / }
           els{ 0 }
        </Code>
      </Parameter>
    </Animation>
  </PartInfo>

...Which is essentially the same as the other 2 fan animations (N1_x_slow and N1_x_blurred) except for the visibility parameters that tell it when to play the animation.

And Tom, I've never tried making the animation sequence longer, but to make it 200 frames I assume that you would simply change "AnimLength" to 200 and modify the timeline in Max/Blender to suit, right? Logically this should make it spin at 1/2 speed and reduce the effect of "shimmering" or jerkiness, but I still haven't found a way to take its angular velocity directly from N1 percentage. Also, would doubling the denominator (3.6) in this code have the same effect?

 

[Heretic]

Angular velocity is defined by the A: var (see unit).

Ditch the "3.6 /" as it cuts animation length from 360 to 100 frames, set the animation length tag to "360" and adjust the time thingy and the keyframes in Max/Blender accordingly.

 

[Osian]

Here is my problem, the left engine has 100 keyframes, the right engine (from this point of view) has 360 Keyframes, and still it is not smooth at all.

https://media.giphy.com/media/3ohhwHJW98oZPsniQU/giphy.gif (here is a gif I have made )

 

[hairyspin]

Do these animations use Linear controllers? If still jerky, change the animations controllers to Smooth and then back to Linear.

 

[F747fly]

Hang on let's determine if this is actually an issue with animation or with the sim. See I remember similar thing a number of years on aircraft I hadn't developed simply due to some lag of my system, how's the frame rate in the sim doing? Is it also constant?
Other than that I agree with Hairyspin on seeing what type of animation you are using.

 

[Osian]

My sim has about 20 to 25 frames, and when I try to make the animation linear blender just wont make the change, I am googling it but nothing comes up, the animations starts normal but slows down till the end of the animation.

 

[F747fly]

If you select the right object, open the graph editor, click on channel, under extrapolation mode select linear extrapolation and that should do it. Works like a charm when I tested this morning.

EDIT: for more details on this you might want to take a look here (https://blender.stackexchange.com/questions/1579/how-do-i-make-animations-a-steady-speed)

 

[euroastar350]

It's a common issue with FSX aircraft and beyond. Also affects propeller (piston and turbine), fan blades, helicopter rotors, tires/wheels. There are a few developers that have successfully implemented smooth rotating props, fan blades, wheels/tires on their aircraft and is something I want to do to my aircraft.

 

[Osian]

If you select the right object, open the graph editor, click on channel, under extrapolation mode select linear extrapolation and that should do it. Works like a charm when I tested this morning.

EDIT: for more details on this you might want to take a look here (https://blender.stackexchange.com/questions/1579/how-do-i-make-animations-a-steady-speed)

Well I tried that and it still slows down in the end.

It's a common issue with FSX aircraft and beyond. Also affects propeller (piston and turbine), fan blades, helicopter rotors, tires/wheels. There are a few developers that have successfully implemented smooth rotating props, fan blades, wheels/tires on their aircraft and is something I want to do to my aircraft.

That's why I asked because I want the engines smooth too, especially with engines like the CFM leap

 

[Heretic]

Still don't understand why everything has to be smooth nowadays. Smooth fuselages with a million polys, smooth animations with a million keyframes, smooth gauges with a million Hertz...

 

[Osian]

Because it looks nicer ? and improves the immersion.

 

[Heretic]

I can think of five million other things that improve immersion and are easily forgotten by a good part of other devs, such a switch sounds in the cockpit, going beyond the standard switches (even without producing a notable effect on actual aircraft systems), something to save the status of custom L: type variables and even just simple rain effects on the cockpit window.

Wasting resources on looks alone is kind of...shallow.

 

[DafaDDDa]

If you select the right object, open the graph editor, click on channel, under extrapolation mode select linear extrapolation and that should do it. Works like a charm when I tested this morning.

EDIT: for more details on this you might want to take a look here (https://blender.stackexchange.com/questions/1579/how-do-i-make-animations-a-steady-speed)

hi,I want to make the model of the airplane with 3Ds Max, but the propeller can't rotate.According to the SDK, the propeller k 0-100 animated frames are generated.MDL file in P3D v3 airplane appears after the screw is not rotating, please consult a useful tutorial, teach me how to make the screw rotation, or making model planes or write. CFG file tutorials (SDK can only solve part. CFG)

 

[terence jordan]

I am trying out my model in FSX and it has the classic jerky/shaky fan animations.
I have seen FSX models with completely smooth fan animations.

Is there a solution for the shaky fan animations ?

Thanks in advance.

I partially solved it.
http://www.fsdeveloper.com/forum/threads/smooth-jet-spool-up-down.441599/