JSBSim Flight Dynamics Model  1.0 (02 March 2017)
An Open Source Flight Dynamics and Control Software Library in C++
FGSwitch Class Reference

Encapsulates a switch for the flight control system. More...

#include <FGSwitch.h>

+ Inheritance diagram for FGSwitch:
+ Collaboration diagram for FGSwitch:

Public Member Functions

 FGSwitch (FGFCS *fcs, Element *element)
 Constructor. More...
 
 ~FGSwitch ()
 Destructor.
 
bool Run (void)
 Executes the switch logic. More...
 
- Public Member Functions inherited from FGFCSComponent
 FGFCSComponent (FGFCS *fcs, Element *el)
 Constructor.
 
virtual ~FGFCSComponent ()
 Destructor.
 
std::string GetName (void) const
 
double GetOutput (void) const
 
virtual double GetOutputPct (void) const
 
std::string GetType (void) const
 
virtual void ResetPastStates (void)
 
void SetDtForFrameCount (int FrameCount)
 
virtual void SetOutput (void)
 
- Public Member Functions inherited from FGJSBBase
 FGJSBBase ()
 Constructor for FGJSBBase.
 
virtual ~FGJSBBase ()
 Destructor for FGJSBBase.
 
void disableHighLighting (void)
 Disables highlighting in the console output.
 
std::string GetVersion (void)
 Returns the version number of JSBSim. More...
 
void PutMessage (const Message &msg)
 Places a Message structure on the Message queue. More...
 
void PutMessage (const std::string &text)
 Creates a message with the given text and places it on the queue. More...
 
void PutMessage (const std::string &text, bool bVal)
 Creates a message with the given text and boolean value and places it on the queue. More...
 
void PutMessage (const std::string &text, int iVal)
 Creates a message with the given text and integer value and places it on the queue. More...
 
void PutMessage (const std::string &text, double dVal)
 Creates a message with the given text and double value and places it on the queue. More...
 
int SomeMessages (void)
 Reads the message on the queue (but does not delete it). More...
 
void ProcessMessage (void)
 Reads the message on the queue and removes it from the queue. More...
 
MessageProcessNextMessage (void)
 Reads the next message on the queue and removes it from the queue. More...
 

Additional Inherited Members

- Public Types inherited from FGJSBBase
enum  { eL = 1, eM, eN }
 Moments L, M, N.
 
enum  { eP = 1, eQ, eR }
 Rates P, Q, R.
 
enum  { eU = 1, eV, eW }
 Velocities U, V, W.
 
enum  { eX = 1, eY, eZ }
 Positions X, Y, Z.
 
enum  { ePhi = 1, eTht, ePsi }
 Euler angles Phi, Theta, Psi.
 
enum  { eDrag = 1, eSide, eLift }
 Stability axis forces, Drag, Side force, Lift.
 
enum  { eRoll = 1, ePitch, eYaw }
 Local frame orientation Roll, Pitch, Yaw.
 
enum  { eNorth = 1, eEast, eDown }
 Local frame position North, East, Down.
 
enum  { eLat = 1, eLong, eRad }
 Locations Radius, Latitude, Longitude.
 
enum  {
  inNone = 0, inDegrees, inRadians, inMeters,
  inFeet
}
 Conversion specifiers.
 
- Static Public Member Functions inherited from FGJSBBase
static double CelsiusToFahrenheit (double celsius)
 Converts from degrees Celsius to degrees Fahrenheit. More...
 
static double CelsiusToKelvin (double celsius)
 Converts from degrees Celsius to degrees Kelvin. More...
 
static double CelsiusToRankine (double celsius)
 Converts from degrees Celsius to degrees Rankine. More...
 
static double Constrain (double min, double value, double max)
 Constrain a value between a minimum and a maximum value.
 
static bool EqualToRoundoff (double a, double b)
 Finite precision comparison. More...
 
static bool EqualToRoundoff (float a, float b)
 Finite precision comparison. More...
 
static bool EqualToRoundoff (float a, double b)
 Finite precision comparison. More...
 
static bool EqualToRoundoff (double a, float b)
 Finite precision comparison. More...
 
static double FahrenheitToCelsius (double fahrenheit)
 Converts from degrees Fahrenheit to degrees Celsius. More...
 
static double FeetToMeters (double measure)
 Converts from feet to meters. More...
 
static double GaussianRandomNumber (void)
 
static double KelvinToCelsius (double kelvin)
 Converts from degrees Kelvin to degrees Celsius. More...
 
static double KelvinToFahrenheit (double kelvin)
 Converts from degrees Kelvin to degrees Fahrenheit. More...
 
static double KelvinToRankine (double kelvin)
 Converts from degrees Kelvin to degrees Rankine. More...
 
static double MachFromVcalibrated (double vcas, double p, double psl, double rhosl)
 Calculate the Mach number from the calibrated airspeed. More...
 
static double PitotTotalPressure (double mach, double p)
 Compute the total pressure in front of the Pitot tube. More...
 
static double RankineToCelsius (double rankine)
 Converts from degrees Rankine to degrees Celsius. More...
 
static double RankineToKelvin (double rankine)
 Converts from degrees Rankine to degrees Kelvin. More...
 
static double sign (double num)
 
static double VcalibratedFromMach (double mach, double p, double psl, double rhosl)
 Calculate the calibrated airspeed from the Mach number. More...
 
- Static Public Attributes inherited from FGJSBBase
static short debug_lvl = 1
 
static char highint [5] = {27, '[', '1', 'm', '\0' }
 highlights text
 
static char halfint [5] = {27, '[', '2', 'm', '\0' }
 low intensity text
 
static char normint [6] = {27, '[', '2', '2', 'm', '\0' }
 normal intensity text
 
static char reset [5] = {27, '[', '0', 'm', '\0' }
 resets text properties
 
static char underon [5] = {27, '[', '4', 'm', '\0' }
 underlines text
 
static char underoff [6] = {27, '[', '2', '4', 'm', '\0' }
 underline off
 
static char fgblue [6] = {27, '[', '3', '4', 'm', '\0' }
 blue text
 
static char fgcyan [6] = {27, '[', '3', '6', 'm', '\0' }
 cyan text
 
static char fgred [6] = {27, '[', '3', '1', 'm', '\0' }
 red text
 
static char fggreen [6] = {27, '[', '3', '2', 'm', '\0' }
 green text
 
static char fgdef [6] = {27, '[', '3', '9', 'm', '\0' }
 default text
 
- Protected Member Functions inherited from FGFCSComponent
virtual void bind ()
 
void Clip (void)
 
void Delay (void)
 
- Protected Member Functions inherited from FGJSBBase
void Debug (int)
 
- Static Protected Member Functions inherited from FGJSBBase
static std::string CreateIndexedPropertyName (const std::string &Property, int index)
 
- Protected Attributes inherited from FGFCSComponent
bool clip
 
double clipmax
 
FGPropertyNode_ptr ClipMaxPropertyNode
 
float clipMaxSign
 
double clipmin
 
FGPropertyNode_ptr ClipMinPropertyNode
 
float clipMinSign
 
unsigned int delay
 
double delay_time
 
double dt
 
FGFCSfcs
 
int index
 
std::vector< std::string > InitNames
 
std::vector< FGPropertyValue * > InitNodes
 
std::vector< float > InitSigns
 
double Input
 
std::vector< std::string > InputNames
 
std::vector< FGPropertyValue * > InputNodes
 
std::vector< float > InputSigns
 
bool IsOutput
 
std::string Name
 
double Output
 
std::vector< double > output_array
 
std::vector< FGPropertyNode_ptr > OutputNodes
 
FGPropertyManagerPropertyManager
 
FGPropertyNode_ptr treenode
 
std::string Type
 
- Static Protected Attributes inherited from FGJSBBase
static const double degtorad = 0.017453292519943295769236907684886
 
static const double fpstokts = 1.0/ktstofps
 
static const double fttom = 0.3048
 
static int gaussian_random_number_phase = 0
 
static const double hptoftlbssec = 550.0
 
static const double in3tom3 = 1.638706E-5
 
static const double inchtoft = 0.08333333
 
static const double inhgtopa = 3386.38
 
static const std::string JSBSim_version = "1.0 " __DATE__ " " __TIME__
 
static const double kgtolb = 2.20462
 
static const double kgtoslug = 0.06852168
 
static const double ktstofps = 1.68781
 
static const double lbtoslug = 1.0/slugtolb
 
static Message localMsg
 
static const double m3toft3 = 1.0/(fttom*fttom*fttom)
 
static double Mair = 28.9645
 
static unsigned int messageId = 0
 
static std::queue< MessageMessages
 
static const std::string needed_cfg_version = "2.0"
 
static const double psftoinhg = 0.014138
 
static const double psftopa = 47.88
 
static const double radtodeg = 57.295779513082320876798154814105
 
static double Reng = 1716.56
 
static double Rstar = 1545.348
 
static const double SHRatio = 1.40
 
static const double slugtolb = 32.174049
 

Detailed Description

Encapsulates a switch for the flight control system.

The switch component models a switch - either on/off or a multi-choice rotary switch. The switch can represent a physical cockpit switch, or can represent a logical switch, where several conditions might need to be satisfied before a particular state is reached. The value of the switch - the output value for the component - is chosen depending on the state of the switch. Each switch is comprised of one or more tests. Each test has a value associated with it. The first test that evaluates to true will set the output value of the switch according to the value parameter belonging to that test. Each test contains one or more conditions, which each must be logically related (if there are more than one) given the value of the logic attribute, and which takes the form:

property conditional property|value

e.g.

qbar ge 21.0

or,

roll_rate == pitch_rate

Within a test, additional tests can be specified, which allows for complex groupings of logical comparisons. Each test contains additional conditions, as well as possibly additional tests.

<switch name="switch1">
<default value="{property|value}"/>
<test logic="{AND|OR}" value="{property|value}">
{property} {conditional} {property|value}
<test logic="{AND|OR}">
{property} {conditional} {property|value}
...
</test>
...
</test>
<test logic="{AND|OR}" value="{property|value}">
{property} {conditional} {property|value}
...
</test>
...
[<output> {property} </output>]
</switch>

Here's an example:

<switch name="roll a/p autoswitch">
<default value="0.0"/>
<test value="fcs/roll-ap-error-summer">
ap/attitude_hold == 1
</test>
</switch>

Note: In the "logic" attribute, "AND" is the default logic, if none is supplied.

The above example specifies that the default value of the component (i.e. the output property of the component, addressed by the property, ap/roll-ap-autoswitch) is 0.0. If or when the attitude hold switch is selected (property ap/attitude_hold takes the value 1), the value of the switch component will be whatever value fcs/roll-ap-error-summer is.

Author
Jon S. Berndt
Version
Id
FGSwitch.h,v 1.18 2013/11/24 11:40:57 bcoconni Exp

Definition at line 137 of file FGSwitch.h.

Constructor & Destructor Documentation

◆ FGSwitch()

FGSwitch ( FGFCS fcs,
Element element 
)

Constructor.

Parameters
fcsa pointer to the parent FGFCS class
elementa pointer to the Element (from the config file XML tree) that represents this switch component

Definition at line 80 of file FGSwitch.cpp.

80  : FGFCSComponent(fcs, element)
81 {
82  string value;
83  struct test *current_test;
84  Element *test_element;
85 
86  FGFCSComponent::bind(); // Bind() this component here in case it is used
87  // in its own definition for a sample-and-hold
88 
89  int num = element->GetNumElements("test");
90  if (element->FindElement("default")) num++;
91  tests.reserve(num);
92 
93  test_element = element->FindElement("default");
94  if (test_element) {
95  current_test = new struct test;
96  current_test->condition = 0;
97  value = test_element->GetAttributeValue("value");
98  current_test->setTestValue(value, Name, PropertyManager);
99  current_test->Default = true;
100  if (delay > 0 && is_number(value)) { // If there is a delay, initialize the
101  for (unsigned int i=0; i<delay-1; i++) { // delay buffer to the default value
102  output_array[i] = atof(value.c_str()); // for the switch if that value is a number.
103  }
104  }
105  tests.push_back(current_test);
106  }
107 
108  test_element = element->FindElement("test");
109  while (test_element) {
110  current_test = new struct test;
111  current_test->condition = new FGCondition(test_element, PropertyManager);
112  value = test_element->GetAttributeValue("value");
113  current_test->setTestValue(value, Name, PropertyManager);
114  tests.push_back(current_test);
115  test_element = element->FindNextElement("test");
116  }
117 
118  Debug(0);
119 }
FGFCSComponent(FGFCS *fcs, Element *el)
Constructor.
+ Here is the call graph for this function:

Member Function Documentation

◆ Run()

bool Run ( void  )
virtual

Executes the switch logic.

Returns
true - always

Reimplemented from FGFCSComponent.

Definition at line 136 of file FGSwitch.cpp.

137 {
138  bool pass = false;
139  double default_output=0.0;
140 
141  for (unsigned int i=0; i<tests.size(); i++) {
142  if (tests[i]->Default) {
143  default_output = tests[i]->GetValue();
144  } else {
145  pass = tests[i]->condition->Evaluate();
146  }
147 
148  if (pass) {
149  Output = tests[i]->GetValue();
150  break;
151  }
152  }
153 
154  if (!pass) Output = default_output;
155 
156  if (delay != 0) Delay();
157  Clip();
158  if (IsOutput) SetOutput();
159 
160  return true;
161 }

The documentation for this class was generated from the following files: