Detailed Description

JSBSim Base class.

This class provides universal constants, utility functions, messaging functions, and enumerated constants to JSBSim.

Author: Jon S. Berndt

Definition at line 78 of file FGJSBBase.h.

#include <FGJSBBase.h>

Inheritance diagram for FGJSBBase:

Collaboration diagram for FGJSBBase:

Classes
class	Filter
	First order, (low pass / lag) filter. More...

struct	Message
	JSBSim Message structure. More...

Public Member Functions
	FGJSBBase ()
	Constructor for FGJSBBase.

virtual	~FGJSBBase ()
	Destructor for FGJSBBase.

Static Public Attributes
JSBSim console output highlighting terms.
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

JSBSim Messaging functions
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 short	debug_lvl = 1

static Message	localMsg

static std::queue< Message >	Messages

static unsigned int	messageId = 0

static constexpr double	radtodeg = 180. / M_PI

static constexpr double	degtorad = M_PI / 180.

static constexpr double	hptoftlbssec = 550.0

static constexpr double	psftoinhg = 0.014138

static constexpr double	psftopa = 47.88

static constexpr double	ktstofps = 1.68781

static constexpr double	fpstokts = 1.0 / ktstofps

static constexpr double	inchtoft = 1.0/12.0

static constexpr double	fttom = 0.3048

static constexpr double	m3toft3 = 1.0/(fttomfttomfttom)

static constexpr double	in3tom3 = inchtoftinchtoftinchtoft/m3toft3

static constexpr double	inhgtopa = 3386.38

static constexpr double	slugtolb = 32.174049
	Note that definition of lbtoslug by the inverse of slugtolb and not to a different constant you can also get from some tables will make lbtoslug*slugtolb == 1 up to the magnitude of roundoff. More...

static constexpr double	lbtoslug = 1.0/slugtolb

static constexpr double	kgtolb = 2.20462

static constexpr double	kgtoslug = 0.06852168

static const std::string	needed_cfg_version = "2.0"

static const std::string	JSBSim_version = JSBSIM_VERSION " " __DATE__ " " __TIME__

static int	gaussian_random_number_phase = 0

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) const
	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...

Message *	ProcessNextMessage (void)
	Reads the next message on the queue and removes it from the queue. More...

void	disableHighLighting (void)
	Disables highlighting in the console output.

static const std::string &	GetVersion (void)
	Returns the version number of JSBSim. More...

static constexpr double	KelvinToFahrenheit (double kelvin)
	Converts from degrees Kelvin to degrees Fahrenheit. More...

static constexpr double	CelsiusToRankine (double celsius)
	Converts from degrees Celsius to degrees Rankine. More...

static constexpr double	RankineToCelsius (double rankine)
	Converts from degrees Rankine to degrees Celsius. More...

static constexpr double	KelvinToRankine (double kelvin)
	Converts from degrees Kelvin to degrees Rankine. More...

static constexpr double	RankineToKelvin (double rankine)
	Converts from degrees Rankine to degrees Kelvin. More...

static constexpr double	FahrenheitToCelsius (double fahrenheit)
	Converts from degrees Fahrenheit to degrees Celsius. More...

static constexpr double	CelsiusToFahrenheit (double celsius)
	Converts from degrees Celsius to degrees Fahrenheit. More...

static constexpr double	CelsiusToKelvin (double celsius)
	Converts from degrees Celsius to degrees Kelvin. More...

static constexpr double	KelvinToCelsius (double kelvin)
	Converts from degrees Kelvin to degrees Celsius. More...

static constexpr double	FeetToMeters (double measure)
	Converts from feet to meters. More...

static double	PitotTotalPressure (double mach, double p)
	Compute the total pressure in front of the Pitot tube. More...

static double	MachFromImpactPressure (double qc, double p)
	Compute the Mach number from the differential pressure (qc) and the static pressure. More...

static double	VcalibratedFromMach (double mach, double p)
	Calculate the calibrated airspeed from the Mach number. More...

static double	MachFromVcalibrated (double vcas, double p)
	Calculate the Mach number from the calibrated airspeed.Based on the formulas in the US Air Force Aircraft Performance Flight Testing Manual (AFFTC-TIH-99-01). More...

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 constexpr double	Constrain (double min, double value, double max)
	Constrain a value between a minimum and a maximum value.

static constexpr double	sign (double num)

static double	GaussianRandomNumber (void)

static std::string	CreateIndexedPropertyName (const std::string &Property, int index)

Member Function Documentation

◆ CelsiusToFahrenheit()

static constexpr double CelsiusToFahrenheit ( double celsius )

inlinestaticconstexpr

Converts from degrees Celsius to degrees Fahrenheit.

Parameters

celsius The temperature in degrees Celsius.

Returns: The temperature in Fahrenheit.

Definition at line 237 of file FGJSBBase.h.

                                                                {
     return celsius * 1.8 + 32.0;
   }

Here is the caller graph for this function:

◆ CelsiusToKelvin()

static constexpr double CelsiusToKelvin ( double celsius )

inlinestaticconstexpr

Converts from degrees Celsius to degrees Kelvin.

Parameters

celsius The temperature in degrees Celsius.

Returns: The temperature in Kelvin.

Definition at line 244 of file FGJSBBase.h.

                                                            {
     return celsius + 273.15;
   }

◆ CelsiusToRankine()

static constexpr double CelsiusToRankine ( double celsius )

inlinestaticconstexpr

Converts from degrees Celsius to degrees Rankine.

Parameters

celsius The temperature in degrees Celsius.

Returns: The temperature in Rankine.

Definition at line 202 of file FGJSBBase.h.

                                                             {
     return celsius * 1.8 + 491.67;
   }

◆ EqualToRoundoff() [1/4]

static bool EqualToRoundoff	(	double	a,
		double	b
	)

inlinestatic

Finite precision comparison.

Parameters

a	first value to compare
b	second value to compare

Returns: if the two values can be considered equal up to roundoff

Definition at line 301 of file FGJSBBase.h.

                                                   {
     double eps = 2.0*DBL_EPSILON;
     return std::fabs(a - b) <= eps * std::max<double>(std::fabs(a), std::fabs(b));
   }

Here is the caller graph for this function:

◆ EqualToRoundoff() [2/4]

static bool EqualToRoundoff	(	double	a,
		float	b
	)

inlinestatic

Finite precision comparison.

Parameters

a	first value to compare
b	second value to compare

Returns: if the two values can be considered equal up to roundoff

Definition at line 327 of file FGJSBBase.h.

                                                  {
     return EqualToRoundoff((float)a, b);
   }

Here is the call graph for this function:

◆ EqualToRoundoff() [3/4]

static bool EqualToRoundoff	(	float	a,
		double	b
	)

inlinestatic

Finite precision comparison.

Parameters

a	first value to compare
b	second value to compare

Returns: if the two values can be considered equal up to roundoff

Definition at line 319 of file FGJSBBase.h.

                                                  {
     return EqualToRoundoff(a, (float)b);
   }

Here is the call graph for this function:

◆ EqualToRoundoff() [4/4]

static bool EqualToRoundoff	(	float	a,
		float	b
	)

inlinestatic

Finite precision comparison.

Parameters

a	first value to compare
b	second value to compare

Returns: if the two values can be considered equal up to roundoff

Definition at line 310 of file FGJSBBase.h.

                                                 {
     float eps = 2.0*FLT_EPSILON;
     return std::fabs(a - b) <= eps * std::max<double>(std::fabs(a), std::fabs(b));
   }

◆ FahrenheitToCelsius()

static constexpr double FahrenheitToCelsius ( double fahrenheit )

inlinestaticconstexpr

Converts from degrees Fahrenheit to degrees Celsius.

Parameters

fahrenheit The temperature in degrees Fahrenheit.

Returns: The temperature in Celsius.

Definition at line 230 of file FGJSBBase.h.

                                                                   {
     return (fahrenheit - 32.0)/1.8;
   }

Here is the caller graph for this function:

◆ FeetToMeters()

static constexpr double FeetToMeters ( double measure )

inlinestaticconstexpr

Converts from feet to meters.

Parameters

measure The length in feet.

Returns: The length in meters.

Definition at line 258 of file FGJSBBase.h.

                                                         {
     return measure*0.3048;
   }

◆ GetVersion()

static const std::string& GetVersion ( void )

inlinestatic

Returns the version number of JSBSim.

Returns: The version number of JSBSim.

Definition at line 185 of file FGJSBBase.h.

185 {return JSBSim_version;}

◆ KelvinToCelsius()

static constexpr double KelvinToCelsius ( double kelvin )

inlinestaticconstexpr

Converts from degrees Kelvin to degrees Celsius.

Parameters

celsius The temperature in degrees Kelvin.

Returns: The temperature in Celsius.

Definition at line 251 of file FGJSBBase.h.

                                                           {
     return kelvin - 273.15;
   }

◆ KelvinToFahrenheit()

static constexpr double KelvinToFahrenheit ( double kelvin )

inlinestaticconstexpr

Converts from degrees Kelvin to degrees Fahrenheit.

Parameters

kelvin The temperature in degrees Kelvin.

Returns: The temperature in Fahrenheit.

Definition at line 195 of file FGJSBBase.h.

                                                              {
     return 1.8*kelvin - 459.4;
   }

◆ KelvinToRankine()

static constexpr double KelvinToRankine ( double kelvin )

inlinestaticconstexpr

Converts from degrees Kelvin to degrees Rankine.

Parameters

kelvin The temperature in degrees Kelvin.

Returns: The temperature in Rankine.

Definition at line 216 of file FGJSBBase.h.

                                                           {
     return kelvin * 1.8;
   }

◆ MachFromImpactPressure()

double MachFromImpactPressure	(	double	qc,
		double	p
	)

static

Compute the Mach number from the differential pressure (qc) and the static pressure.

Based on the formulas in the US Air Force Aircraft Performance Flight Testing Manual (AFFTC-TIH-99-01).

Parameters

qc	The differential/impact pressure
p	Pressure in psf

Returns: The Mach number

Definition at line 275 of file FGJSBBase.cpp.

 {
   double A = qc / p + 1;
   double M = sqrt(5.0*(pow(A, 1. / 3.5) - 1));  // Equation (4.12)
  
   if (M > 1.0)
     for (unsigned int i = 0; i<10; i++)
       M = 0.8812848543473311*sqrt(A*pow(1 - 1.0 / (7.0*M*M), 2.5));  // Equation (4.17)
  
   return M;
 }

◆ MachFromVcalibrated()

double MachFromVcalibrated	(	double	vcas,
		double	p
	)

static

Calculate the Mach number from the calibrated airspeed.Based on the formulas in the US Air Force Aircraft Performance Flight Testing Manual (AFFTC-TIH-99-01).

Parameters

vcas	The calibrated airspeed (CAS) in ft/s
p	Pressure in psf

Returns: The Mach number

Definition at line 300 of file FGJSBBase.cpp.

 {
   double asl = FGAtmosphere::StdDaySLsoundspeed;
   double psl = FGAtmosphere::StdDaySLpressure;
   double qc = PitotTotalPressure(vcas / asl, psl) - psl;
  
   return MachFromImpactPressure(qc, p);
 }

Here is the caller graph for this function:

◆ PitotTotalPressure()

double PitotTotalPressure	(	double	mach,
		double	p
	)

static

Compute the total pressure in front of the Pitot tube.

It uses the Rayleigh formula for supersonic speeds (See "Introduction to Aerodynamics of a Compressible Fluid - H.W. Liepmann, A.E. Puckett - Wiley & sons (1947)" §5.4 pp 75-80)

Parameters

mach	The Mach number
p	Pressure in psf

Returns: The total pressure in front of the Pitot tube in psf

Definition at line 245 of file FGJSBBase.cpp.

 {
   if (mach < 0) return p;
   if (mach < 1)    //calculate total pressure assuming isentropic flow
     return p*pow((1 + 0.2*mach*mach),3.5);
   else {
     // shock in front of pitot tube, we'll assume its normal and use
     // the Rayleigh Pitot Tube Formula, i.e. the ratio of total
     // pressure behind the shock to the static pressure in front of
     // the normal shock assumption should not be a bad one -- most supersonic
     // aircraft place the pitot probe out front so that it is the forward
     // most point on the aircraft.  The real shock would, of course, take
     // on something like the shape of a rounded-off cone but, here again,
     // the assumption should be good since the opening of the pitot probe
     // is very small and, therefore, the effects of the shock curvature
     // should be small as well. AFAIK, this approach is fairly well accepted
     // within the aerospace community
  
     // The denominator below is zero for Mach ~ 0.38, for which
     // we'll never be here, so we're safe
  
     return p*166.92158009316827*pow(mach,7.0)/pow(7*mach*mach-1,2.5);
   }
 }

Here is the caller graph for this function:

◆ ProcessMessage()

void ProcessMessage ( void )

Reads the message on the queue and removes it from the queue.

This function also prints out the message.

Definition at line 148 of file FGJSBBase.cpp.

 {
   if (Messages.empty()) return;
   localMsg = Messages.front();
  
   while (SomeMessages()) {
       switch (localMsg.type) {
       case JSBSim::FGJSBBase::Message::eText:
         cout << localMsg.messageId << ": " << localMsg.text << endl;
         break;
       case JSBSim::FGJSBBase::Message::eBool:
         cout << localMsg.messageId << ": " << localMsg.text << " " << localMsg.bVal << endl;
         break;
       case JSBSim::FGJSBBase::Message::eInteger:
         cout << localMsg.messageId << ": " << localMsg.text << " " << localMsg.iVal << endl;
         break;
       case JSBSim::FGJSBBase::Message::eDouble:
         cout << localMsg.messageId << ": " << localMsg.text << " " << localMsg.dVal << endl;
         break;
       default:
         cerr << "Unrecognized message type." << endl;
         break;
       }
       Messages.pop();
       if (SomeMessages()) localMsg = Messages.front();
       else break;
   }
  
 }

◆ ProcessNextMessage()

FGJSBBase::Message * ProcessNextMessage ( void )

Reads the next message on the queue and removes it from the queue.

This function also prints out the message.

Returns: a pointer to the message, or NULL if there are no messages.

Definition at line 180 of file FGJSBBase.cpp.

 {
   if (Messages.empty()) return NULL;
   localMsg = Messages.front();
  
   Messages.pop();
   return &localMsg;
 }

◆ PutMessage() [1/5]

void PutMessage ( const Message & msg )

Places a Message structure on the Message queue.

Parameters

msg	pointer to a Message structure

Returns: pointer to a Message structure

Definition at line 90 of file FGJSBBase.cpp.

 {
   Messages.push(msg);
 }

◆ PutMessage() [2/5]

void PutMessage ( const std::string & text )

Creates a message with the given text and places it on the queue.

Parameters

text	message text

Returns: pointer to a Message structure

Definition at line 97 of file FGJSBBase.cpp.

 {
   Message msg;
   msg.text = text;
   msg.messageId = messageId++;
   msg.subsystem = "FDM";
   msg.type = Message::eText;
   Messages.push(msg);
 }

◆ PutMessage() [3/5]

void PutMessage	(	const std::string &	text,
		bool	bVal
	)

Creates a message with the given text and boolean value and places it on the queue.

Parameters

text	message text
bVal	boolean value associated with the message

Returns: pointer to a Message structure

Definition at line 109 of file FGJSBBase.cpp.

 {
   Message msg;
   msg.text = text;
   msg.messageId = messageId++;
   msg.subsystem = "FDM";
   msg.type = Message::eBool;
   msg.bVal = bVal;
   Messages.push(msg);
 }

◆ PutMessage() [4/5]

void PutMessage	(	const std::string &	text,
		double	dVal
	)

Creates a message with the given text and double value and places it on the queue.

Parameters

text	message text
dVal	double value associated with the message

Returns: pointer to a Message structure

Definition at line 135 of file FGJSBBase.cpp.

 {
   Message msg;
   msg.text = text;
   msg.messageId = messageId++;
   msg.subsystem = "FDM";
   msg.type = Message::eDouble;
   msg.dVal = dVal;
   Messages.push(msg);
 }

◆ PutMessage() [5/5]

void PutMessage	(	const std::string &	text,
		int	iVal
	)

Creates a message with the given text and integer value and places it on the queue.

Parameters

text	message text
iVal	integer value associated with the message

Returns: pointer to a Message structure

Definition at line 122 of file FGJSBBase.cpp.

 {
   Message msg;
   msg.text = text;
   msg.messageId = messageId++;
   msg.subsystem = "FDM";
   msg.type = Message::eInteger;
   msg.iVal = iVal;
   Messages.push(msg);
 }

◆ RankineToCelsius()

static constexpr double RankineToCelsius ( double rankine )

inlinestaticconstexpr

Converts from degrees Rankine to degrees Celsius.

Parameters

rankine The temperature in degrees Rankine.

Returns: The temperature in Celsius.

Definition at line 209 of file FGJSBBase.h.

                                                             {
     return (rankine - 491.67)/1.8;
   }

Here is the caller graph for this function:

◆ RankineToKelvin()

static constexpr double RankineToKelvin ( double rankine )

inlinestaticconstexpr

Converts from degrees Rankine to degrees Kelvin.

Parameters

rankine The temperature in degrees Rankine.

Returns: The temperature in Kelvin.

Definition at line 223 of file FGJSBBase.h.

                                                            {
     return rankine/1.8;
   }

Here is the caller graph for this function:

◆ SomeMessages()

int SomeMessages ( void ) const

inline

Reads the message on the queue (but does not delete it).

Returns: 1 if some messages

Definition at line 173 of file FGJSBBase.h.

173 { return !Messages.empty(); }

◆ VcalibratedFromMach()

double VcalibratedFromMach	(	double	mach,
		double	p
	)

static

Calculate the calibrated airspeed from the Mach number.

Based on the formulas in the US Air Force Aircraft Performance Flight Testing Manual (AFFTC-TIH-99-01).

Parameters

mach	The Mach number
p	Pressure in psf

Returns: The calibrated airspeed (CAS) in ft/s

Definition at line 289 of file FGJSBBase.cpp.

 {
   double asl = FGAtmosphere::StdDaySLsoundspeed;
   double psl = FGAtmosphere::StdDaySLpressure;
   double qc = PitotTotalPressure(mach, p) - p;
  
   return asl * MachFromImpactPressure(qc, psl);  
 }

Here is the caller graph for this function:

Member Data Documentation

◆ slugtolb

constexpr double slugtolb = 32.174049

staticconstexprprotected

Note that definition of lbtoslug by the inverse of slugtolb and not to a different constant you can also get from some tables will make lbtoslug*slugtolb == 1 up to the magnitude of roundoff.

So converting from slug to lb and back will yield to the original value you started with up to the magnitude of roundoff. Taken from units gnu commandline tool

Definition at line 366 of file FGJSBBase.h.

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

Detailed Description

Classes

Public Member Functions

Static Public Attributes

JSBSim Messaging functions

Member Function Documentation

◆ CelsiusToFahrenheit()

◆ CelsiusToKelvin()

◆ CelsiusToRankine()

◆ EqualToRoundoff() [1/4]

◆ EqualToRoundoff() [2/4]

◆ EqualToRoundoff() [3/4]

◆ EqualToRoundoff() [4/4]

◆ FahrenheitToCelsius()

◆ FeetToMeters()

◆ GetVersion()

◆ KelvinToCelsius()

◆ KelvinToFahrenheit()

◆ KelvinToRankine()

◆ MachFromImpactPressure()

◆ MachFromVcalibrated()

◆ PitotTotalPressure()

◆ ProcessMessage()

◆ ProcessNextMessage()

◆ PutMessage() [1/5]

◆ PutMessage() [2/5]

◆ PutMessage() [3/5]

◆ PutMessage() [4/5]

◆ PutMessage() [5/5]

◆ RankineToCelsius()

◆ RankineToKelvin()

◆ SomeMessages()

◆ VcalibratedFromMach()

Member Data Documentation

◆ slugtolb