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Flying-Cat.xml
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Flying-Cat.xml
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<?xml version="1.0"?>
<!--
Flying-Cat Hot Air Balloon flight model for JSBSim.
Copyright (C) Herbert Wagner 2016
-->
<?xml-stylesheet type="text/xsl" href="http://jsbsim.sourceforge.net/JSBSim.xsl"?>
<fdm_config name="Flying-Cat" version="2.0" release="ALPHA"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://jsbsim.sourceforge.net/JSBSim.xsd">
<!--
==== Metrics ===============================================================
-->
<metrics>
<documentation>
NOTE: The origo of the structural frame coordinate system is in the center
of the bottom of the basket. changed!
x/y/z = back/right/up
</documentation>
<wingarea unit="M2"> 126.0 </wingarea> <!-- Must be large to avoid -->
<wingspan unit="M"> 6.0 </wingspan> <!-- numerical problems. -->
<chord unit="FT"> 0 </chord>
<htailarea unit="FT2"> 0 </htailarea>
<htailarm unit="FT"> 0 </htailarm>
<vtailarea unit="FT2"> 0 </vtailarea>
<vtailarm unit="FT"> 0 </vtailarm>
<location name="AERORP" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 16.2 </z>
</location>
<location name="EYEPOINT" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 0.975 </z>
</location>
<location name="VRP" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 0.05 </z>
</location>
</metrics>
<!--
==== Mass balance ==========================================================
-->
<mass_balance>
<documentation> not right
Masses in KG gesamt 10000 kg
Envelope 1620
Net 150 ---1770
Gondel 920
Drag rope 98
Instruments 350
Ausrüstung 500 ---1868
34*180 KG GasContainer ---6100
Load ring 80
Burner 150 ---230
Valve 20
Valve cord 20 ---40
</documentation>
<documentation>
Rough model to estimate CG and inertia tensor.
% Envelope + net (Thin sphere)
m_e = 147.87 % KG
r = 6.185 % M
% Basket + Drag rope + Instruments + Com. gear (Point mass)
m_b = 64.864 % KG
% Load ring (Point mass)
m_lr = 9.072 % KG
% Top valve + cord (Point mass)
m_v = 8.165 % KG
% CG for envelope: (0, 0, 15.545)
% Inertia tensor for envelope. Since we take CG_e as CG we are done.
Ixx = 2/3 * m_e * r^2 2/3 * 1770 * 13*13
Iyy = 2/3 * m_e * r^2
Izz = 2/3 * m_e * r^2
Ixy = Ixz = Iyz = 0
</documentation>
<ixx unit="KG*M2"> 15000000 </ixx>
<iyy unit="KG*M2"> 15000000 </iyy>
<izz unit="KG*M2"> 15000000 </izz>
<ixy unit="KG*M2"> -0 </ixy>
<ixz unit="KG*M2"> -0 </ixz>
<iyz unit="KG*M2"> -0 </iyz>
<emptywt unit="KG"> 407 </emptywt>
<location name="CG" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 3.0 </z>
</location>
<pointmass name="Ballast">
<location name="POINTMASS" unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 1.0 </z>
</location>
<weight unit="KG"> 610.0 </weight>
</pointmass>
<pointmass name="Pilot">
<weight unit="KG"> 100.0 </weight>
<location name="POINTMASS" unit="M">
<x> -0.5 </x>
<y> 0.5 </y>
<z> 1.0 </z>
</location>
</pointmass>
<pointmass name="Propane Burner Fuel">
<weight unit="KG"> 180.0 </weight>
<location name="POINTMASS" unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 1.2 </z>
</location>
</pointmass>
<pointmass name="Basket">
<weight unit="KG"> 186.0 </weight>
<location name="POINTMASS" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 1.0 </z>
</location>
</pointmass>
<pointmass name="Load ring">
<weight unit="KG"> 60.0 </weight>
<location name="POINTMASS" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 2.9 </z>
</location>
</pointmass>
<pointmass name="Top valve">
<weight unit="KG"> 10.0 </weight>
<location name="POINTMASS" unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 25.5 </z>
</location>
</pointmass>
</mass_balance>
<!--
=== Gas cell ===============================================================
1. Hot Air Balloon
-->
<buoyant_forces>
<!-- External environment properties -->
<!-- Set from Nasal. -->
<property> environment/sun-angle-rad </property>
<!-- Gas cell constants -->
<!-- Conductivity [lb / (K ft sec)] (Guess) -->
<property value="0.57"> buoyant_forces/heat-coeffs/conductivity </property>
<!-- Emissivity [0,1] (Guess) -->
<property value="0.05"> buoyant_forces/heat-coeffs/emissivity </property>
<property value="0.0"> fcs/blower-valve-cmd-norm </property>
<!-- Hot Air Balloon -->
<gas_cell type="AIR">
<location unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 16.2 </z>
</location>
<x_radius unit="M"> 9.5 </x_radius>
<y_radius unit="M"> 9.5 </y_radius>
<z_radius unit="M"> 9.5 </z_radius>
<fullness> 0.0 </fullness>
<max_overpressure unit="PA"> 0.0 </max_overpressure>
<valve_coefficient unit="M4*SEC/KG"> 0.15 </valve_coefficient>
<heat>
<function name="buoyant_forces/gas-cell/dU_conduction">
<product>
<value> 12207.57 </value>
<value> 0.25 </value>
<property> buoyant_forces/heat-coeffs/conductivity </property>
<difference>
<property> atmosphere/T-R </property>
<property> buoyant_forces/gas-cell/temp-R </property>
</difference>
</product>
</function>
<function name="buoyant_forces/gas-cell/dU_radiation">
<product>
<value> 0.1714e-8 </value>
<property> buoyant_forces/heat-coeffs/emissivity </property>
<value> 12207.57 </value>
<value> 0.50 </value>
<difference>
<pow>
<property> atmosphere/T-R </property>
<value> 4.0 </value>
</pow>
<pow>
<property> buoyant_forces/gas-cell/temp-R </property>
<value> 4.0 </value>
</pow>
</difference>
</product>
</function>
<function name="buoyant_forces/gas-cell/dU_solar_radiation">
<product>
<value> 7.2330 </value>
<value> 12207.57 </value>
<value> 130.00 </value>
<value> 0.02 </value>
<value> 0.50 </value>
<property> environment/sun-angle-rad </property>
<max>
<value> 0.0 </value>
<difference>
<value> 1.5708 </value>
<property> environment/sun-angle-rad </property>
</difference>
</max>
</product>
</function>
<function name="buoyant_forces/gas-cell/dU_flame">
<product>
<value> 450000 </value>
<property> fcs/flame-valve-cmd-norm </property>
</product>
</function>
<function name="buoyant_forces/gas-cell/dU_air-flow">
<product>
<value> 300 </value>
<property> fcs/blower-valve-cmd-norm</property>
</product>
</function>
</heat>
</gas_cell>
</buoyant_forces>
<!--
=== Ground reactions =======================================================
-->
<ground_reactions>
<contact type="STRUCTURE" name="BASKET_LOWER_CENTER">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> -0.07 </z>
</location>
<static_friction> 5 </static_friction>
<dynamic_friction> 5 </dynamic_friction>
<rolling_friction> 3.0 </rolling_friction>
<spring_coeff unit="N/M"> 24000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 22000 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_LOWER_CORNER_1">
<location unit="M">
<x> -1.30 </x>
<y> -0.65 </y>
<z> -0.07 </z>
</location>
<static_friction> 5 </static_friction>
<dynamic_friction> 5 </dynamic_friction>
<rolling_friction> 3.0 </rolling_friction>
<spring_coeff unit="N/M"> 24000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 22000 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_LOWER_CORNER_2">
<location unit="M">
<x> -1.30 </x>
<y> 0.65 </y>
<z> -0.07 </z>
</location>
<static_friction> 5 </static_friction>
<dynamic_friction> 5 </dynamic_friction>
<rolling_friction> 3.0 </rolling_friction>
<spring_coeff unit="N/M"> 24000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 22000 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_LOWER_CORNER_3">
<location unit="M">
<x> 1.30 </x>
<y> -0.65 </y>
<z> -0.07 </z>
</location>
<static_friction> 5 </static_friction>
<dynamic_friction> 5 </dynamic_friction>
<rolling_friction> 3.0 </rolling_friction>
<spring_coeff unit="N/M"> 24000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 22000 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_LOWER_CORNER_4">
<location unit="M">
<x> 1.30 </x>
<y> 0.65 </y>
<z> -0.07 </z>
</location>
<static_friction> 5 </static_friction>
<dynamic_friction> 5 </dynamic_friction>
<rolling_friction> 3.0 </rolling_friction>
<spring_coeff unit="N/M"> 24000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 22000 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_UPPER_CORNER_1">
<location unit="M">
<x> -1.30 </x>
<y> -0.72 </y>
<z> 2.08 </z>
</location>
<static_friction> 0.5 </static_friction>
<dynamic_friction> 0.5 </dynamic_friction>
<rolling_friction> 1.0 </rolling_friction>
<spring_coeff unit="N/M"> 22000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 6600 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_UPPER_CORNER_2">
<location unit="M">
<x> -1.30 </x>
<y> 0.72 </y>
<z> 2.08 </z>
</location>
<static_friction> 0.5 </static_friction>
<dynamic_friction> 0.5 </dynamic_friction>
<rolling_friction> 1.0 </rolling_friction>
<spring_coeff unit="N/M"> 22000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 6600 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_UPPER_CORNER_3">
<location unit="M">
<x> 1.30 </x>
<y> -0.72 </y>
<z> 2.08 </z>
</location>
<static_friction> 0.5 </static_friction>
<dynamic_friction> 0.5 </dynamic_friction>
<rolling_friction> 1.0 </rolling_friction>
<spring_coeff unit="N/M"> 22000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 6600 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="BASKET_UPPER_CORNER_4">
<location unit="M">
<x> 1.30 </x>
<y> 0.72 </y>
<z> 2.08 </z>
</location>
<static_friction> 0.5 </static_friction>
<dynamic_friction> 0.5 </dynamic_friction>
<rolling_friction> 1.0 </rolling_friction>
<spring_coeff unit="N/M"> 22000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 6600 </damping_coeff>
</contact>
<contact type="STRUCTURE" name="TOP_OF_ENVELOPE">
<location unit="M">
<x> 0 </x>
<y> 0 </y>
<z> 55.0 </z>
</location>
<static_friction> 0.5 </static_friction>
<dynamic_friction> 0.5 </dynamic_friction>
<rolling_friction> 1.0 </rolling_friction>
<spring_coeff unit="N/M"> 22000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 6600 </damping_coeff>
</contact>
<contact type="BOGEY" name="fixedrightfront">
<location unit="M">
<x> 2 </x>
<y> 2 </y>
<z> -2.0 </z>
</location>
<static_friction> 5.5 </static_friction>
<dynamic_friction> 5.5 </dynamic_friction>
<rolling_friction> 5.0 </rolling_friction>
<spring_coeff unit="N/M"> 1000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 700 </damping_coeff>
<brake_group>CENTER</brake_group>
<retractable>1</retractable>
</contact>
<contact type="BOGEY" name="fixedleftfront">
<location unit="M">
<x> 2 </x>
<y> -2 </y>
<z> -2.0 </z>
</location>
<static_friction> 5.5 </static_friction>
<dynamic_friction> 5.5 </dynamic_friction>
<rolling_friction> 5.0 </rolling_friction>
<spring_coeff unit="N/M"> 1000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 700 </damping_coeff>
<brake_group>CENTER</brake_group>
<retractable>1</retractable>
</contact>
<contact type="BOGEY" name="fixedrightback">
<location unit="M">
<x> -2 </x>
<y> 2 </y>
<z> -2.0 </z>
</location>
<static_friction> 5.5 </static_friction>
<dynamic_friction> 5.5 </dynamic_friction>
<rolling_friction> 5.0 </rolling_friction>
<spring_coeff unit="N/M"> 1000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 700 </damping_coeff>
<brake_group>CENTER</brake_group>
<retractable>1</retractable>
</contact>
<contact type="BOGEY" name="fixedleftback">
<location unit="M">
<x> -2 </x>
<y> -2 </y>
<z> -2.0 </z>
</location>
<static_friction> 5.5 </static_friction>
<dynamic_friction> 5.5 </dynamic_friction>
<rolling_friction> 5.0 </rolling_friction>
<spring_coeff unit="N/M"> 1000 </spring_coeff>
<damping_coeff type="SQUARE" unit="N/M2/SEC2"> 700 </damping_coeff>
<brake_group>CENTER</brake_group>
<retractable>1</retractable>
</contact>
</ground_reactions>
<propulsion/>
<!--
=== Flight control system ==================================================
-->
<flight_control name="FGFCS">
<!-- CHANNELS -->
<channel name="Gas">
<summer name="Gas Valve Sum">
<input>fcs/gas-valve-cmd-norm</input>
<clipto>
<min>0</min>
<max>1</max>
</clipto>
</summer>
<fcs_function name="Gas Valve Control">
<function>
<sum>
<property>fcs/gas-valve-sum</property>
<product>
<value>1.0</value>
<property>fcs/rip-cmd-norm</property>
</product>
</sum>
</function>
<output>buoyant_forces/gas-cell/valve_open</output>
</fcs_function>
</channel>
<channel name="Joystick input">
<pure_gain name="Aileron wrapper L">
<input> fcs/aileron-cmd-norm </input>
<gain> 1 </gain>
<output> fcs/left-aileron-pos-norm </output>
</pure_gain>
<pure_gain name="Aileron wrapper R">
<input> fcs/aileron-cmd-norm </input>
<gain> -1 </gain>
<output> fcs/right-aileron-pos-norm </output>
</pure_gain>
<pure_gain name="Elevator wrapper">
<input> fcs/elevator-cmd-norm </input>
<gain> 1 </gain>
<output> fcs/elevator-pos-norm </output>
</pure_gain>
<pure_gain name="Rudder wrapper">
<input> fcs/rudder-cmd-norm </input>
<gain> 1 </gain>
<output> fcs/rudder-pos-norm </output>
</pure_gain>
</channel>
<channel name="Fixed Standing">
<kinematic name="fcs/gear-control">
<input>gear/gear-cmd-norm</input>
<traverse>
<setting>
<position> 0 </position>
<time> 0 </time>
</setting>
<setting>
<position> 1 </position>
<time> 1 </time>
</setting>
</traverse>
<output>gear/gear-pos-norm</output>
</kinematic>
</channel>
</flight_control>
<!--
==== External reactions ====================================================
-->
<external_reactions>
<!-- Help variables for mass -->
<property value="0.65"> external_reactions/x-const </property>
<property value="0.65"> external_reactions/y-const </property><!--0.65 neu-->
<property value="-2100"> external_reactions/z-const </property><!--0.1 -->
<property value="0.0"> fcs/mooring-cmd-norm </property>
<property value="0.0"> fcs/mooring2-cmd-norm </property>
<force name="added-mass-bx" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 16.2 </z>
</location>
<direction>
<x> 1.0 </x>
<y> 0.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="added-mass-by" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 16.2 </z>
</location>
<direction>
<x> 0.0 </x>
<y> 1.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="added-mass-bz" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 16.2 </z>
</location>
<direction>
<x> 0.0 </x>
<y> 0.0 </y>
<z> 1.0 </z>
</direction>
</force>
<force name="added-mass-pitch[0]" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 16.2 </z>
</location>
<direction>
<x> 1.0 </x>
<y> 0.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="added-mass-pitch[1]" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.0 </y>
<z> 16.2 </z>
</location>
<direction>
<x> 1.0 </x>
<y> 0.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="added-mass-yaw[0]" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> -0.30 </y>
<z> 0.0 </z>
</location>
<direction>
<x> 1.0 </x>
<y> 0.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="added-mass-yaw[1]" frame="BODY">
<location unit="M">
<x> 0.0 </x>
<y> 0.30 </y>
<z> 0.0 </z>
</location>
<direction>
<x> 1.0 </x>
<y> 0.0 </y>
<z> 0.0 </z>
</direction>
</force>
<force name="mooring" frame="BODY">
<location unit="M"><!--Sandsacks -->
<x>0</x>
<y>0 </y>
<z>-10 </z>
</location>
<direction>
<x>0</x>
<y>0</y>
<z>1</z>
</direction>
</force>
<force name="mooring2" frame="BODY">
<location unit="M"><!--Anchor, fixed to ground -->
<x>0</x>
<y>0 </y>
<z>-10 </z>
</location>
<direction>
<x>0</x>
<y>0</y>
<z>1</z>
</direction>
</force>
<force name="turnvalvel" frame="BODY">
<location unit="M"><!--Turn Valve left-->
<x>9</x>
<y>9</y>
<z>16</z>
</location>
<direction>
<x>0</x>
<y>1</y>
<z>0</z>
</direction>
</force>
<force name="turnvalver" frame="BODY">
<location unit="M"><!--Turn Valve right-->
<x>9</x>
<y>9</y>
<z>16</z>
</location>
<direction>
<x>0</x>
<y>-1</y>
<z>0</z>
</direction>
</force>
</external_reactions>
<!--
=== Aerodynamics ===========================================================
-->
<system name="constants">
<!-- Aerodynamic constants. -->
<property value="62.34"> aero/constants/length-ft </property>
<property value="62.34"> aero/constants/diameter-ft </property>
<property value="7772.55"> aero/constants/length-diameter-ft2 </property>
<property value="126827.68"> aero/constants/volume-ft3 </property>
<!-- Added mass constants. -->
<property value="-0.20"> aero/constants/added-mass/k-axial </property><!-- -0.50 -->
<property value="-0.70"> aero/constants/added-mass/k-traverse </property><!-- -0.50 -->
<property value="-0.23"> aero/constants/added-mass/k-rotational </property><!-- -0.0 -->
<property value="1.00"> aero/constants/added-mass/tweak-factor </property>
<property value="0.00"> position/ground-altitude </property>
<property value="0"> fcs/takeoffweight </property>
</system>
<system file="animation-jsbsim"/>
<system file="airship_added_mass"/>
<system file="steady-behaviour"/>
<aerodynamics>
<!-- Wild guess: D = K A q_inf -->
<!-- A = cross sectional area (120.2m^2); -->
<!--
NOTE: The drag coefficients has been estimated using a virtual
wind-tunnel setup in gerris, a fluid dynamics simulator.
The viability of this approach is not yet evaluated.
-->
<axis name="DRAG">
<function name="aero/coefficient/CDh">
<description>Drag</description>
<product>
<property>aero/qbar-psf</property>
<value> 8300.0 </value>
<table>
<independentVar lookup="row">aero/alpha-deg</independentVar>
<tableData>
-135 0.033088
-90 0.024652
-45 0.033088
0 0.020219
45 0.067882
135 0.067882
</tableData>
</table>
</product>
</function>
</axis>
<axis name="ROLL">
<function name="aero/coefficient/Clp">
<description>Roll_moment_due_to_roll_rate_(roll_damping)</description>
<!-- Wild guess: K * basket area * moment arm * "p_inf" -->
<!-- The current version is just a hack to make the balloon stable. -->
<product>
<value> 0.001 </value>
</product>
</function>
</axis>
<axis name="PITCH">
<function name="aero/coefficient/Cmq">
<description>Pitch_moment_due_to_pitch_rate_(damping)</description>
<!-- Wild guess: K * basket area * moment arm * "p_inf" -->
<!-- The current version is just a hack to make the balloon stable. -->
<product>
<value> 0.001 </value>
</product>
</function>
</axis>
</aerodynamics>
</fdm_config>