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ehofman 2006-02-08 09:15:57 +00:00
parent 3cdea0705d
commit ae77c7d75a
10 changed files with 356 additions and 189 deletions
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6
src/FDM/JSBSim/initialization/FGTrim.h
View file

@ -108,7 +108,8 @@ CLASS DOCUMENTATION
at those conditions? Check the speed, altitude, configuration (flaps, at those conditions? Check the speed, altitude, configuration (flaps,
gear, etc.), weight, cg, and anything else that may be relevant. gear, etc.), weight, cg, and anything else that may be relevant.
Example usage:<pre> Example usage:
@code
FGFDMExec* FDMExec = new FGFDMExec(); FGFDMExec* FDMExec = new FGFDMExec();
FGInitialCondition* fgic = new FGInitialCondition(FDMExec); FGInitialCondition* fgic = new FGInitialCondition(FDMExec);
@ -119,7 +120,8 @@ CLASS DOCUMENTATION
if( !fgt.DoTrim() ) { if( !fgt.DoTrim() ) {
cout << "Trim Failed" << endl; cout << "Trim Failed" << endl;
} }
fgt.Report(); </pre> fgt.Report();
@endcode
@author Tony Peden @author Tony Peden
@version "$Id$" @version "$Id$"
*/ */

8
src/FDM/JSBSim/math/FGFunction.cpp
View file

@ -77,7 +77,13 @@ FGFunction::FGFunction(FGPropertyManager* propMan, Element* el, string prefix)
// data types // data types
if (operation == string("property")) { if (operation == string("property")) {
property_name = element->GetDataLine(); property_name = element->GetDataLine();
Parameters.push_back(new FGPropertyValue(PropertyManager->GetNode(property_name))); FGPropertyManager* newNode = PropertyManager->GetNode(property_name);
if (newNode == 0) {
cerr << "The property " << property_name << " is undefined." << endl;
abort();
} else {
Parameters.push_back(new FGPropertyValue( newNode ));
}
} else if (operation == string("value")) { } else if (operation == string("value")) {
Parameters.push_back(new FGRealValue(element->GetDataAsNumber())); Parameters.push_back(new FGRealValue(element->GetDataAsNumber()));
} else if (operation == string("table")) { } else if (operation == string("table")) {

6
src/FDM/JSBSim/math/FGTable.cpp
View file

@ -158,6 +158,12 @@ FGTable::FGTable(FGPropertyManager* propMan, Element* el) : PropertyManager(prop
property_string = axisElement->GetDataLine(); property_string = axisElement->GetDataLine();
node = PropertyManager->GetNode(property_string); node = PropertyManager->GetNode(property_string);
if (node == 0) {
cerr << "IndependenVar property, " << property_string
<< " in Table definition is not defined." << endl;
abort();
}
lookup_axis = axisElement->GetAttributeValue("lookup"); lookup_axis = axisElement->GetAttributeValue("lookup");
if (lookup_axis == string("row")) { if (lookup_axis == string("row")) {
lookupProperty[eRow] = node; lookupProperty[eRow] = node;

85
src/FDM/JSBSim/models/FGFCS.h
View file

@ -81,67 +81,110 @@ CLASS DOCUMENTATION
which comprise the control laws for an axis are defined sequentially in which comprise the control laws for an axis are defined sequentially in
the configuration file. For instance, for the X-15: the configuration file. For instance, for the X-15:
<pre> @code
\<flight_control name="X-15 SAS"> <flight_control name="X-15 SAS">
\<channel> <channel>
\<component name="Pitch Trim Sum" type="SUMMER"> <summer name="Pitch Trim Sum">
<input> fcs/elevator-cmd-norm </input> <input> fcs/elevator-cmd-norm </input>
<input> fcs/pitch-trim-cmd-norm </input> <input> fcs/pitch-trim-cmd-norm </input>
<clipto> <clipto>
<min>-1</min> <min>-1</min>
<max>1</max> <max>1</max>
</clipto> </clipto>
\</component> </summer>
\<component name="Pitch Command Scale" TYPE="AEROSURFACE_SCALE"> <aerosurface_scale name="Pitch Command Scale">
<input> fcs/pitch-trim-sum </input> <input> fcs/pitch-trim-sum </input>
<limit> <range>
<min> -50 </min> <min> -50 </min>
<max> 50 </max> <max> 50 </max>
</limit> </range>
\</component> </aerosurface_scale>
... etc. ... etc.
</pre> @endcode
In the above case we can see the first few components of the pitch channel In the above case we can see the first few components of the pitch channel
defined. The input to the first component, as can be seen in the "Pitch trim defined. The input to the first component (a summer), as can be seen in the "Pitch trim
sum" component, is really the sum of two parameters: elevator command (from sum" component, is really the sum of two parameters: elevator command (from
the stick - a pilot input), and pitch trim. The type of this component is the stick - a pilot input), and pitch trim.
"Summer".
The next component created is an aerosurface scale component - a type of The next component created is an aerosurface scale component - a type of
gain (see the LoadFCS() method for insight on how the various types of gain (see the LoadFCS() method for insight on how the various types of
components map into the actual component classes). This continues until the components map into the actual component classes). This continues until the
final component for an axis when the final component for an axis when the
\<output> element specifies where the output is supposed to go. See the \<output> element is usually used to specify where the output is supposed to go. See the
individual components for more information on how they are mechanized. individual components for more information on how they are mechanized.
Another option for the flight controls portion of the config file is that in Another option for the flight controls portion of the config file is that in
addition to using the "NAME" attribute in, addition to using the "NAME" attribute in,
<pre> @code
\<flight_control name="X-15 SAS"> \<flight_control name="X-15 SAS">
</pre> @endcode
one can also supply a filename: one can also supply a filename:
<pre> @code
\<flight_control name="X-15 SAS" file="X15.xml"> \<flight_control name="X-15 SAS" file="X15.xml">
\</flight_control> \</flight_control>
</pre> @endcode
In this case, the FCS would be read in from another file. In this case, the FCS would be read in from another file.
<h2>Properties</h2>
@property fcs/aileron-cmd-norm normalized aileron command
@property fcs/elevator-cmd-norm normalized elevator command
@property fcs/rudder-cmd-norm
@property fcs/steer-cmd-norm
@property fcs/flap-cmd-norm
@property fcs/speedbrake-cmd-norm
@property fcs/spoiler-cmd-norm
@property fcs/pitch-trim-cmd-norm
@property fcs/roll-trim-cmd-norm
@property fcs/yaw-trim-cmd-norm
@property gear/gear-cmd-norm
@property fcs/left-aileron-pos-rad
@property fcs/left-aileron-pos-deg
@property fcs/left-aileron-pos-norm
@property fcs/mag-left-aileron-pos-rad
@property fcs/right-aileron-pos-rad
@property fcs/right-aileron-pos-deg
@property fcs/right-aileron-pos-norm
@property fcs/mag-right-aileron-pos-rad
@property fcs/elevator-pos-rad
@property fcs/elevator-pos-deg
@property fcs/elevator-pos-norm
@property fcs/mag-elevator-pos-rad
@property fcs/rudder-pos-rad
@property fcs/rudder-pos-deg
@property fcs/rudder-pos-norm
@property fcs/mag-rudder-pos-rad
@property fcs/flap-pos-rad
@property fcs/flap-pos-deg
@property fcs/flap-pos-norm
@property fcs/speedbrake-pos-rad
@property fcs/speedbrake-pos-deg
@property fcs/speedbrake-pos-norm
@property fcs/mag-speedbrake-pos-rad
@property fcs/spoiler-pos-rad
@property fcs/spoiler-pos-deg
@property fcs/spoiler-pos-norm
@property fcs/mag-spoiler-pos-rad
@property gear/gear-pos-norm
@author Jon S. Berndt @author Jon S. Berndt
@version $Id$ @version $Revision$
@see FGFCSComponent @see FGFCSComponent
@see FGXMLElement @see FGXMLElement
@see FGGain @see FGGain
@see FGSummer @see FGSummer
@see FGSwitch @see FGSwitch
@see FGFCSFunction
@see FGCondition
@see FGGradient @see FGGradient
@see FGFilter @see FGFilter
@see FGDeadBand @see FGDeadBand
@see FGKinemat
*/ */
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@ -461,9 +504,7 @@ public:
//@} //@}
/** Loads the Flight Control System. /** Loads the Flight Control System.
The FGAircraft instance is actually responsible for reading the config file Load() is called from FGFDMExec.
and calling the various Load() methods of the other systems, passing in
the XML Element instance pointer. Load() is called from FGAircraft.
@param el pointer to the Element instance @param el pointer to the Element instance
@return true if succesful */ @return true if succesful */
bool Load(Element* el); bool Load(Element* el);

7
src/FDM/JSBSim/models/flight_control/FGFCSComponent.cpp
View file

@ -54,6 +54,7 @@ FGFCSComponent::FGFCSComponent(FGFCS* _fcs, Element* element) : fcs(_fcs)
Input = Output = clipmin = clipmax = 0.0; Input = Output = clipmin = clipmax = 0.0;
OutputNode = treenode = 0; OutputNode = treenode = 0;
ClipMinPropertyNode = ClipMaxPropertyNode = 0; ClipMinPropertyNode = ClipMaxPropertyNode = 0;
clipMinSign = clipMaxSign = 1.0;
IsOutput = clip = false; IsOutput = clip = false;
string input, clip_string; string input, clip_string;
@ -121,12 +122,14 @@ FGFCSComponent::FGFCSComponent(FGFCS* _fcs, Element* element) : fcs(_fcs)
if (clip_el) { if (clip_el) {
clip_string = clip_el->FindElementValue("min"); clip_string = clip_el->FindElementValue("min");
if (clip_string.find_first_not_of("+-.0123456789") != string::npos) { // it's a property if (clip_string.find_first_not_of("+-.0123456789") != string::npos) { // it's a property
if (clip_string[0] == '-') clipMinSign = -1.0;
ClipMinPropertyNode = PropertyManager->GetNode( clip_string ); ClipMinPropertyNode = PropertyManager->GetNode( clip_string );
} else { } else {
clipmin = clip_el->FindElementValueAsNumber("min"); clipmin = clip_el->FindElementValueAsNumber("min");
} }
clip_string = clip_el->FindElementValue("max"); clip_string = clip_el->FindElementValue("max");
if (clip_string.find_first_not_of("+-.0123456789") != string::npos) { // it's a property if (clip_string.find_first_not_of("+-.0123456789") != string::npos) { // it's a property
if (clip_string[0] == '-') clipMaxSign = -1.0;
ClipMaxPropertyNode = PropertyManager->GetNode( clip_string ); ClipMaxPropertyNode = PropertyManager->GetNode( clip_string );
} else { } else {
clipmax = clip_el->FindElementValueAsNumber("max"); clipmax = clip_el->FindElementValueAsNumber("max");
@ -166,8 +169,8 @@ bool FGFCSComponent::Run(void)
void FGFCSComponent::Clip(void) void FGFCSComponent::Clip(void)
{ {
if (clip) { if (clip) {
if (ClipMinPropertyNode != 0) clipmin = ClipMinPropertyNode->getDoubleValue(); if (ClipMinPropertyNode != 0) clipmin = clipMinSign*ClipMinPropertyNode->getDoubleValue();
if (ClipMaxPropertyNode != 0) clipmax = ClipMaxPropertyNode->getDoubleValue(); if (ClipMaxPropertyNode != 0) clipmax = clipMaxSign*ClipMaxPropertyNode->getDoubleValue();
if (Output > clipmax) Output = clipmax; if (Output > clipmax) Output = clipmax;
else if (Output < clipmin) Output = clipmin; else if (Output < clipmin) Output = clipmin;
} }

3
src/FDM/JSBSim/models/flight_control/FGFCSComponent.h
View file

@ -69,7 +69,7 @@ CLASS DOCUMENTATION
/** Base class for JSBSim Flight Control System Components. /** Base class for JSBSim Flight Control System Components.
The Flight Control System (FCS) for JSBSim consists of the FCS container The Flight Control System (FCS) for JSBSim consists of the FCS container
class (see \URL[FGFCS]{FGFCS.html}), the FGFCSComponent base class, and the class (see FGFCS), the FGFCSComponent base class, and the
component classes from which can be constructed a string, or channel. See: component classes from which can be constructed a string, or channel. See:
- FGSwitch - FGSwitch
@ -119,6 +119,7 @@ protected:
double Input; double Input;
double Output; double Output;
double clipmax, clipmin; double clipmax, clipmin;
float clipMinSign, clipMaxSign;
bool IsOutput; bool IsOutput;
bool clip; bool clip;

203
src/FDM/JSBSim/models/flight_control/FGFilter.h
View file

@ -4,7 +4,7 @@
Author: Jon S. Berndt Author: Jon S. Berndt
Date started: 4/2000 Date started: 4/2000
------------- Copyright (C) ------------- ------------- Copyright (C) 2000 Jon S. Berndt jsb@hal-pc.org -------------
This program is free software; you can redistribute it and/or modify it under This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software the terms of the GNU General Public License as published by the Free Software
@ -57,115 +57,163 @@ CLASS DOCUMENTATION
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
/** Encapsulates a filter for the flight control system. /** Encapsulates a filter for the flight control system.
The filter component can simulate any filter up to second order. The The filter component can simulate any first or second order filter. The
Tustin substitution is used to take filter definitions from LaPlace space to the Tustin substitution is used to take filter definitions from LaPlace space to the
time domain. The general format for a filter specification is: time domain. The general format for a filter specification is:
<pre> @code
\<component name="name" type="type"> <typename name="name">
\<input> property \</input> <input> property </input>
\<c1> value \<c/1> <c1> value </c1>
[\<c2> value \<c/2>] [<c2> value </c2>]
[\<c3> value \<c/3>] [<c3> value </c3>]
[\<c4> value \<c/4>] [<c4> value </c4>]
[\<c5> value \<c/5>] [<c5> value </c5>]
[\<c6> value \<c/6>] [<c6> value </c6>]
[\<output> property \<output>] [<clipto>
\</component> <min> {[-]property name | value} </min>
</pre> <max> {[-]property name | value} </max>
</clipto>]
[<output> property </output>]
</typename>
@endcode
For a lag filter of the form, For a lag filter of the form,
<pre>
@code
C1 C1
------ ------
s + C1 s + C1
</pre> @endcode
the corresponding filter definition is: the corresponding filter definition is:
<pre>
\<component name="name" type="LAG_FILTER"> @code
\<input> property \</input> <lag_filter name="name">
\<c1> value \<c/1> <input> property </input>
[\<output> property \<output>] <c1> value </c1>
\</component> [<clipto>
</pre> <min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<output> property <output>]
</lag_filter>
@endcode
As an example, for the specific filter: As an example, for the specific filter:
<pre>
@code
600 600
------ ------
s + 600 s + 600
</pre> @endcode
the corresponding filter definition could be: the corresponding filter definition could be:
<pre>
\<component name="Heading Roll Error Lag" type="LAG_FILTER"> @code
\<input> fcs/heading-command \</input> <lag_filter name="Heading Roll Error Lag">
\<c1> 600 \</c1> <input> fcs/heading-command </input>
\</component> <c1> 600 </c1>
</pre> </lag_filter>
@endcode
For a lead-lag filter of the form: For a lead-lag filter of the form:
<pre>
@code
C1*s + C2 C1*s + C2
--------- ---------
C3*s + C4 C3*s + C4
</pre> @endcode
The corresponding filter definition is: The corresponding filter definition is:
<pre>
\<component name="name" type="LEAD_LAG_FILTER"> @code
\<input> property \</input> <lead_lag_filter name="name">
\<c1> value \<c/1> <input> property </input>
\<c2> value \<c/2> <c1> value <c/1>
\<c3> value \<c/3> <c2> value <c/2>
\<c4> value \<c/4> <c3> value <c/3>
[\<output> property \<output>] <c4> value <c/4>
\</component> [<clipto>
</pre> <min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<output> property </output>]
</lead_lag_filter>
@endcode
For a washout filter of the form: For a washout filter of the form:
<pre>
@code
s s
------ ------
s + C1 s + C1
</pre> @endcode
The corresponding filter definition is: The corresponding filter definition is:
<pre>
\<component name="name" type="WASHOUT_FILTER"> @code
\<input> property \</input> <washout_filter name="name">
\<c1> value \</c1> <input> property </input>
[\<output> property \<output>] <c1> value </c1>
\</component> [<clipto>
</pre> <min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<output> property </output>]
</washout_filter>
@endcode
For a second order filter of the form: For a second order filter of the form:
<pre>
@code
C1*s^2 + C2*s + C3 C1*s^2 + C2*s + C3
------------------ ------------------
C4*s^2 + C5*s + C6 C4*s^2 + C5*s + C6
</pre> @endcode
The corresponding filter definition is: The corresponding filter definition is:
<pre>
\<component name="name" type="SECOND_ORDER_FILTER"> @code
\<input> property \</input> <second_order_filter name="name">
\<c1> value \<c/1> <input> property </input>
\<c2> value \<c/2> <c1> value </c1>
\<c3> value \<c/3> <c2> value </c2>
\<c4> value \<c/4> <c3> value </c3>
\<c5> value \<c/5> <c4> value </c4>
\<c6> value \<c/6> <c5> value </c5>
[\<output> property \<output>] <c6> value </c6>
\</component> [<clipto>
</pre> <min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<output> property </output>]
</second_order_filter>
@endcode
For an integrator of the form: For an integrator of the form:
<pre>
@code
C1 C1
--- ---
s s
</pre> @endcode
The corresponding filter definition is: The corresponding filter definition is:
<pre>
\<component name="name" type="INTEGRATOR"> @code
\<input> property \</input> <integrator name="name">
\<c1> value \<c/1> <input> property </input>
[\<trigger> property \</trigger>] <c1> value </c1>
[\<output> property \<output>] [<trigger> property </trigger>]
\</component> [<clipto>
</pre> <min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<output> property </output>]
</integrator>
@endcode
For the integrator, the trigger features the following behavior. If the trigger For the integrator, the trigger features the following behavior. If the trigger
property value is: property value is:
- 0: no action is taken - the output is calculated normally - 0: no action is taken - the output is calculated normally
@ -177,7 +225,8 @@ is so that the last component in a "string" can copy its value to the appropriat
output, such as the elevator, or speedbrake, etc. output, such as the elevator, or speedbrake, etc.
@author Jon S. Berndt @author Jon S. Berndt
@version $Id$ @version $Revision$
*/ */
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

221
src/FDM/JSBSim/models/flight_control/FGGain.h
View file

@ -1,10 +1,10 @@
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
Header: FGGain.h Header: FGGain.h
Author: Author: Jon Berndt
Date started: Date started: 1998 ?
------------- Copyright (C) ------------- ------------- Copyright (C) 1998 by Jon S. Berndt, jsb@hal-pc.org -------------
This program is free software; you can redistribute it and/or modify it under This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software the terms of the GNU General Public License as published by the Free Software
@ -68,98 +68,155 @@ CLASS DOCUMENTATION
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/ %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%*/
/** Encapsulates a gain component for the flight control system. /** Encapsulates a gain component for the flight control system.
The gain component merely multiplies the input by a gain. The form of the The gain component merely multiplies the input by a gain. The <b>pure gain</b> form
gain component specification is: of the component specification is:
<pre>
\<component name="name" type="PURE_GAIN">
\<input> property \</input>
\<gain> value \</gain>
[\<output> property \</output>]
\</component>
</pre>
Note: as is the case with the Summer component, the input property name may be
immediately preceded by a minus sign to invert that signal.
The scheduled gain component multiplies the input by a variable gain that is @code
<pure_gain name="name">
<input> {[-]property} </input>
<gain> {property name | value} </gain>
[<clipto>
<min> {property name | value} </min>
<max> {property name | value} </max>
</clipto>]
[<output> {property} </output>]
</pure_gain>
@endcode
Example:
@code
<pure_gain name="Roll AP Wing Leveler">
<input>fcs/attitude/sensor/phi-rad</input>
<gain>2.0</gain>
<clipto>
<min>-0.255</min>
<max>0.255</max>
</clipto>
</pure_gain>
@endcode
Note: the input property name may be immediately preceded by a minus sign to
invert that signal.
The <b>scheduled gain</b> component multiplies the input by a variable gain that is
dependent on another property (such as qbar, altitude, etc.). The lookup dependent on another property (such as qbar, altitude, etc.). The lookup
mapping is in the form of a table. This kind of component might be used, for mapping is in the form of a table. This kind of component might be used, for
example, in a case where aerosurface deflection must only be commanded to example, in a case where aerosurface deflection must only be commanded to
acceptable settings - i.e at higher qbar the commanded elevator setting might acceptable settings - i.e at higher qbar the commanded elevator setting might
be attenuated. The form of the scheduled gain component specification is: be attenuated. The form of the scheduled gain component specification is:
<pre>
\<COMPONENT NAME="name" TYPE="SCHEDULED_GAIN"> @code
INPUT \<property> <scheduled_gain name="name">
[GAIN \<value>] <input> {[-]property} </input>
SCHEDULED_BY \<property> <table>
ROWS \<number_of_rows> <tableData>
\<lookup_value gain_value> ...
? </tableData>
[CLIPTO \<min> \<max> 1] </table>
[OUTPUT \<property>] [<clipto>
\</COMPONENT> <min> {[-]property name | value} </min>
</pre> <max> {[-]property name | value} </max>
</clipto>]
[<gain> {property name | value} </gain>]
[<output> {property} </output>]
</scheduled_gain>
@endcode
Example:
@code
<scheduled_gain name="Scheduled Steer Pos Deg">
<input>fcs/steer-cmd-norm</input>
<table>
<independentVar>velocities/vg-fps</independentVar>
<tableData>
10.0 80.0
50.0 15.0
150.0 2.0
</tableData>
</table>
<gain>0.017</gain>
<output>fcs/steer-pos-rad</output>
</scheduled_gain>
@endcode
An overall GAIN may be supplied that is multiplicative with the scheduled gain. An overall GAIN may be supplied that is multiplicative with the scheduled gain.
Note: as is the case with the Summer component, the input property name may Note: the input property name may be immediately preceded by a minus sign to
be immediately preceded by a minus sign to invert that signal. invert that signal.
Here is an example of a scheduled gain component specification: In the example above, we see the utility of the overall gain value in
<pre>
\<COMPONENT NAME="Pitch Scheduled Gain 1" TYPE="SCHEDULED_GAIN">
INPUT fcs/pitch-gain-1
GAIN 0.017
SCHEDULED_BY fcs/elevator-pos-rad
ROWS 22
-0.68 -26.548
-0.595 -20.513
-0.51 -15.328
-0.425 -10.993
-0.34 -7.508
-0.255 -4.873
-0.17 -3.088
-0.085 -2.153
0 -2.068
0.085 -2.833
0.102 -3.088
0.119 -3.377
0.136 -3.7
0.153 -4.057
0.17 -4.448
0.187 -4.873
0.272 -7.508
0.357 -10.993
0.442 -15.328
0.527 -20.513
0.612 -26.548
0.697 -33.433
\</COMPONENT>
</pre>
In the example above, we see the utility of the overall GAIN value in
effecting a degrees-to-radians conversion. effecting a degrees-to-radians conversion.
The aerosurface scale component is a modified version of the simple gain The <b>aerosurface scale</b> component is a modified version of the simple gain
component. The normal purpose component. The purpose for this component is to take control inputs from the
for this component is to take control inputs that range from -1 to +1 or domain minimum and maximum, as specified (or from -1 to +1 by default) and
from 0 to +1 and scale them to match the expected inputs to a flight control scale them to map to a specified range. This can be done, for instance, to match
system. For instance, the normal and expected ability of a pilot to push or the component outputs to the expected inputs to a flight control system.
pull on a control stick is about 50 pounds. The input to the pitch channelb
lock diagram of a flight control system is in units of pounds. Yet, the The zero_centered element dictates whether the domain-to-range mapping is linear
joystick control input is usually in a range from -1 to +1. The form of the or centered about zero. For example, if zero_centered is false, and if the domain
aerosurface scaling component specification is: or range is not symmetric about zero, and an input value is zero, the output
<pre> will not be zero. Let's say that the domain is min=-2 and max=+4, with a range
\<COMPONENT NAME="name" TYPE="AEROSURFACE_SCALE"> of -1 to +1. If the input is 0.0, then the "normalized" input is calculated to
INPUT \<property> be 33% of the way from the minimum to the maximum. That input would be mapped
MIN \<value> to an output of -0.33, which is 33% of the way from the range minimum to maximum.
MAX \<value> If zero_centered is set to true (or 1) then an input of 0.0 will be mapped to an
[GAIN \<value>] output of 0.0, although if either the domain or range are unsymmetric about
[OUTPUT \<property>] 0.0, then the scales for the positive and negative portions of the input domain
\</COMPONENT> (above and below 0.0) will be different. The zero_centered element is true by
</pre> default. Note that this feature may be important for some control surface mappings,
Note: as is the case with the Summer component, the input property name may be where the maximum upper and lower deflections may be different, but where a zero
immediately preceded by a minus sign to invert that signal. setting is desired to be the "undeflected" value, and where full travel of the
stick is desired to cause a full deflection of the control surface.
The form of the aerosurface scaling component specification is:
@code
<aerosurface_scale name="name">
<input> {[-]property name} </input>
<domain>
<min> {value} </min> <!-- If omitted, default is -1.0 ->
<max> {value} </max> <!-- If omitted, default is 1.0 ->
</domain>
<range>
<min> {value} </min> <!-- If omitted, default is 0 ->
<max> {value} </max> <!-- If omitted, default is 0 ->
</range>
<zero_centered< value </zero_centered>
[<clipto>
<min> {[-]property name | value} </min>
<max> {[-]property name | value} </max>
</clipto>]
[<gain> {property name | value} </gain>]
[<output> {property} </output>]
</aerosurface_scale>
@endcode
Note: the input property name may be immediately preceded by a minus sign to
invert that signal.
For instance, the normal and expected ability of a
pilot to push or pull on a control stick is about 50 pounds. The input to the
pitch channel block diagram of a flight control system is often in units of pounds.
Yet, the joystick control input usually defines a span from -1 to +1. The aerosurface_scale
form of the gain component maps the inputs to the desired output range. The example
below shoes a simple aerosurface_scale component that maps the joystick
input to a range of +/- 50, which represents pilot stick force in pounds for the F-16.
@code
<aerosurface_scale name="Pilot input">
<input>fcs/elevator-cmd-norm</input>
<range>
<min> -50 </min> <!-- If omitted, default is 0 ->
<max> 50 </max> <!-- If omitted, default is 0 ->
</range>
</aerosurface_scale>
@endcode
@author Jon S. Berndt @author Jon S. Berndt
@version $Id$ @version $Revision$
*/ */
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

2
src/FDM/JSBSim/models/flight_control/FGSensor.h
View file

@ -99,6 +99,8 @@ will be *anywhere* from 0.95 to 1.05 of the actual "perfect" value at any time -
even varying all the way from 0.95 to 1.05 in adjacent frames - whatever the delta even varying all the way from 0.95 to 1.05 in adjacent frames - whatever the delta
time. time.
@author Jon S. Berndt
@version $Revision$
*/ */
/*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% /*%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

2
src/FDM/JSBSim/models/propulsion/FGPropeller.cpp
View file

@ -223,7 +223,7 @@ double FGPropeller::GetPowerRequired(void)
cPReq = cPower->GetValue(J); cPReq = cPower->GetValue(J);
} else { // Variable pitch prop } else { // Variable pitch prop
if (MaxRPM != MinRPM) { // fixed-speed prop if (MaxRPM != MinRPM) { // constant speed prop
// do normal calculation when propeller is neither feathered nor reversed // do normal calculation when propeller is neither feathered nor reversed
if (!Feathered) { if (!Feathered) {