#4 Control aircraft from aileron/elevator/rudder/throttle

[eusebiu]

Hello.
I want to control an aircraft using the properties:
fcs/left-aileron-pos-rad, fcs/right-aileron-pos-rad, fcs/elevator-pos-rad, fcs/rudder-pos-rad (I guess these are the deflection of control surfaces - If I am mistaken, please correct me) and fcs/throttle-cmd-norm (is this throttle lever position?). I modified c1722.xml script as follows:
<runscript xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nonamespaceschemalocation="http://jsbsim.sf.net/JSBSimScript.xsd" name="At-altitude autopilot test setup."></runscript>

<use aircraft="c172x" initialize="reset01">
<run start="0.0" end="200" dt="0.00833333"></run></use>

<event name="Engine start">
  <condition>simulation/sim-time-sec  ge  0.25</condition>
  <set name="fcs/throttle-cmd-norm" value="0.65"/>
  <set name="fcs/mixture-cmd-norm" value="0.87"/>
  <set name="propulsion/magneto_cmd" value="3"/>
  <set name="propulsion/starter_cmd" value="1"/>
  <set name="ap/heading_hold" value="0"/>
  <notify>
    <property>velocities/vc-kts</property>
    <property>position/h-agl-ft</property>
  </notify>
</event>

<event name="Elevation">
  <condition>simulation/sim-time-sec  ge  0.50</condition>
  <set name="fcs/elevator-pos-rad" value="0.15"/>
  <set name="fcs/throttle-cmd-norm" value="0.9"/>
  <notify>
    <property>velocities/vc-kts</property>
    <property>position/h-agl-ft</property>
  </notify>
</event>

reset01.xml is:
<initialize name="reset01">
<ubody unit="FT/SEC"> 0.0 </ubody>
<vbody unit="FT/SEC"> 0.0 </vbody>
<wbody unit="FT/SEC"> 0.0 </wbody>
<latitude unit="DEG"> 28.0 </latitude>
<longitude unit="DEG"> -90.0 </longitude>
<phi unit="DEG"> 0.0 </phi>
<theta unit="DEG"> 0.0 </theta>
<psi unit="DEG"> 0.0 </psi>
<altitude unit="FT"> 1000.0 </altitude>
<winddir unit="DEG"> 0.0 </winddir>
<vwind unit="FT/SEC"> 0.0 </vwind>
</initialize>

I expect that the aircraft would follow a linear path and the altitude should increase.

Can you help me with an example that uses all 5 commands?

Thanks,
Eusebiu

[Ron Jensen]

For the record: fcs/left-aileron-pos-rad, fcs/right-aileron-pos-rad, fcs/elevator-pos-rad and fcs/rudder-pos-rad are outputs of the flight control system. They are indeed control surface deflections but are not directly controllable.

Set the properties fcs/aileron-cmd-norm, fcs/elevator-cmd-norm and fcs/rudder-cmd-norm to control them. All of these properties are intended to be in the range of +/-1.

fcs/throttle-cmd-norm is the correct property to control the first engine. It is intended to be in the range 0..1