fgdata/Aircraft/c172p/Systems/KAP140.xml

<?xml version="1.0"?>
<!-- KAP 140 Autopilot Configuration -->
<!-- Each component is evaluated in the order specified.  You can make up -->
<!-- property names to pass the result of one component on to a subsequent -->
<!-- component. -->
<PropertyList>

  <filter>
    <name>heading bug error computer/normalizer</name>
    <debug>false</debug>
    <type>gain</type>
    <input>
      <property>autopilot/settings/heading-bug-deg</property>
      <offset>
        <property>instrumentation/heading-indicator/indicated-heading-deg</property>
        <scale>-1.0</scale>
      </offset>
    </input>
    <output>autopilot/internal/heading-bug-error-deg</output>
    <period>
      <min>-180</min>
      <max>180</max>
    </period>
    <gain>1.0</gain>
  </filter>


  <!-- =============================================================== -->
  <!-- Roll Axis Modes                                                 -->
  <!-- =============================================================== -->

  <!-- Nav hold (NAV) Mode-->

  <pid-controller>
    <name>Nav hold (NAV) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/nav-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/instrumentation/nav/heading-needle-deflection</prop>
    </input>
    <reference>
      <value>0.0</value>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-intercept-angle</prop>
    </output>
    <config>
      <Kp>2.0</Kp>        <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>       <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-45.0</u_min> <!-- minimum output clamp -->
      <u_max>45.0</u_max>  <!-- maximum output clamp -->
    </config>
  </pid-controller>

  <!-- Approach hold (APR) Mode-->
  <pid-controller>
    <name>Approach hold (APR) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/apr-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/instrumentation/nav/heading-needle-deflection</prop>
    </input>
    <reference>
      <value>0.0</value>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-intercept-angle</prop>
    </output>
    <config>
      <Kp>2.0</Kp>        <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>       <!-- integrator time -->
      <Td>0.001</Td>    <!-- derivator time -->
      <u_min>-45.0</u_min> <!-- minimum output clamp -->
      <u_max>45.0</u_max>  <!-- maximum output clamp -->
    </config>
  </pid-controller>

  <!-- Backcourse hold (REV) Mode-->
  <pid-controller>
    <name>Backcourse hold (REV) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/rev-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/instrumentation/nav/heading-needle-deflection</prop>
      <scale>-1.0</scale>
    </input>
    <reference>
      <value>0.0</value>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-intercept-angle</prop>
    </output>
    <config>
      <Kp>2.0</Kp>        <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>       <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-45.0</u_min> <!-- minimum output clamp -->
      <u_max>45.0</u_max>  <!-- maximum output clamp -->
    </config>
  </pid-controller>

  <!-- Heading Select (HDG) Mode -->

  <pid-controller>
    <name>Heading Select (HDG) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/hdg-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/autopilot/internal/heading-bug-error-deg</prop>
<!--      <prop>/instrumentation/gps/true-bug-error-deg</prop> -->
    </input>
    <reference>
      <prop>/autopilot/KAP140/settings/target-intercept-angle</prop>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-turn-rate</prop>
    </output>
    <config>
      <Kp>-0.05</Kp>        <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>       <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-1.0</u_min> <!-- minimum output clamp -->
      <u_max>1.0</u_max>  <!-- maximum output clamp -->
    </config>
  </pid-controller>

  <!-- Wing leveler (ROL) Mode --> 

  <pid-controller>
    <name>Wing Leveler (ROL) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/roll-axis</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/instrumentation/turn-indicator/indicated-turn-rate</prop>
    </input>
    <reference>
      <prop>/autopilot/KAP140/settings/target-turn-rate</prop>
    </reference>
    <output>
      <prop>/controls/flight/aileron</prop>
    </output>
    <config>
      <Kp>0.15</Kp>        <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>       <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-0.25</u_min> <!-- minimum output clamp -->
      <u_max>0.25</u_max>  <!-- maximum output clamp -->
    </config>
  </pid-controller>

  <!-- =============================================================== -->
  <!-- Pitch Axis Modes                                                -->
  <!-- =============================================================== -->

  <!-- Altitude Hold (ALT) Mode --> 
  <pid-controller>
    <name>Altitude Hold (ALT) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/alt-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/systems/static[0]/pressure-inhg[0]</prop>
    </input>
    <reference>
      <prop>/autopilot/KAP140/settings/target-alt-pressure</prop>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-pressure-rate</prop>
    </output>
    <config>
      <Kp>0.125</Kp>      <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>12.0</Ti>        <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-0.007</u_min> <!-- minimum output clamp -->
      <u_max>0.007</u_max>  <!-- maximum output clamp -->
    </config>
   </pid-controller>

   <!-- Glideslope Hold (GS) Mode --> 
  <pid-controller>
    <name>Glideslope Hold (GS) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/gs-hold</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/instrumentation/nav/gs-needle-deflection-norm</prop>
    </input>
    <reference>
      <value>0.0</value>
    </reference>
    <output>
      <prop>/autopilot/KAP140/settings/target-pressure-rate</prop>
    </output>
    <config>
      <Kp>0.025</Kp>      <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>15.0</Ti>        <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-0.001</u_min> <!-- minimum output clamp -->
      <u_max>0.017</u_max>  <!-- maximum output clamp -->
    </config>
   </pid-controller>

  <filter>
    <name>static port pressure rate computer</name>
    <debug>false</debug>
    <type>derivative</type>
    <input>systems/static[0]/pressure-inhg</input>
    <output>autopilot/internal/pressure-rate</output>
    <filter-time>1.0</filter-time>
  </filter>

   <filter>
    <name>pressure-rate-filter</name>
    <debug>false</debug>
    <type>double-exponential</type>
    <input>/autopilot/internal/pressure-rate</input>
    <output>/autopilot/internal/filtered-pressure-rate</output>
    <filter-time>0.1</filter-time>
   </filter>

  <!-- Vertical Speed (VS) Mode --> 
  <pid-controller>
    <name>Vertical Speed (VS) Mode</name>
    <debug>false</debug>
    <enable>
      <prop>/autopilot/KAP140/locks/pitch-axis</prop>
      <value type="bool">true</value>
    </enable>
    <input>
      <prop>/autopilot/internal/filtered-pressure-rate</prop>
    </input>
    <reference>
      <prop>/autopilot/KAP140/settings/target-pressure-rate</prop>
    </reference>
    <output>
      <prop>/controls/flight/elevator</prop>
    </output>
    <config>
      <Kp>5.0</Kp>      <!-- proportional gain -->
      <beta>1.0</beta>    <!-- input value weighing factor -->
      <alpha>0.1</alpha>  <!-- low pass filter weighing factor -->
      <gamma>0.0</gamma>  <!-- input value weighing factor for -->
                          <!-- unfiltered derivative error -->
      <Ti>4.0</Ti>        <!-- integrator time -->
      <Td>0.0</Td>    <!-- derivator time -->
      <u_min>-0.5</u_min> <!-- minimum output clamp -->
      <u_max>0.5</u_max>  <!-- maximum output clamp -->
    </config>
   </pid-controller>

</PropertyList>