[Jsbsim-devel] Aerosurface scale

[Erik H. <er...@eh...>]

Hi,

I've tried to get the normalized surface positions working for the F-16 
and after some testing I managed to do so. But there is one thing that I 
don't fully understand;

For the F-16 I calculate the normalized surface position based on the 
pilots input and the current forces on the aircraft using a PID 
controller. Then I use the outcome to scale the aero surfaces. But to 
get the animation working it is not enough to name the summer "Rudder 
Pos Norm" (which should create fcs/rudder-pos-norm) like this:

<summer name="Rudder Pos Norm">
</summer>

But I actually have to scale back the fcs/rudder-pos-rad property using:

<aerosurface_scale name="Rudder Normalized">
    <input>fcs/rudder-pos-rad</input>
    <domain>
       <min>-1</min>
       <max>1</max>
    </domain>
    <range>
       <min>-0.524</min>
       <max>0.524</max>
    </range>
    <output>fcs/rudder-pos-norm</output>
</aerosurface_scale>

Which is basically the reverse of the aerosurface_scale to get the 
position i degrees and radians. Is there any good reason for that?

Erik

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