JSBSim::FGAccelerometer Class Reference

Encapsulates a Accelerometer component for the flight control system. More...

#include <FGAccelerometer.h>

Inherits JSBSim::FGSensor, and JSBSim::FGSensorOrientation.

Public Member Functions
	FGAccelerometer (FGFCS *fcs, Element *element)
	~FGAccelerometer ()
bool	Run (void) override
Public Member Functions inherited from JSBSim::FGSensor
	FGSensor (FGFCS *fcs, Element *element)
virtual	~FGSensor ()
void	SetFailLow (double val)
void	SetFailHigh (double val)
void	SetFailStuck (double val)
double	GetFailLow (void) const
double	GetFailHigh (void) const
double	GetFailStuck (void) const
int	GetQuantized (void) const
bool	Run (void) override
void	ResetPastStates (void) override
Public Member Functions inherited from JSBSim::FGFCSComponent
	FGFCSComponent (FGFCS *fcs, Element *el)
	Constructor.
virtual	~FGFCSComponent ()
	Destructor.
virtual void	SetOutput (void)
double	GetOutput (void) const
std::string	GetName (void) const
std::string	GetType (void) const
virtual double	GetOutputPct (void) const
Public Member Functions inherited from JSBSim::FGJSBBase
	FGJSBBase ()
	Constructor for FGJSBBase.
virtual	~FGJSBBase ()
	Destructor for FGJSBBase.
void	PutMessage (const Message &msg)
	Places a Message structure on the Message queue.
void	PutMessage (const std::string &text)
	Creates a message with the given text and places it on the queue.
void	PutMessage (const std::string &text, bool bVal)
	Creates a message with the given text and boolean value and places it on the queue.
void	PutMessage (const std::string &text, int iVal)
	Creates a message with the given text and integer value and places it on the queue.
void	PutMessage (const std::string &text, double dVal)
	Creates a message with the given text and double value and places it on the queue.
int	SomeMessages (void) const
	Reads the message on the queue (but does not delete it).
void	ProcessMessage (void)
	Reads the message on the queue and removes it from the queue.
Message *	ProcessNextMessage (void)
	Reads the next message on the queue and removes it from the queue.
void	disableHighLighting (void)
	Disables highlighting in the console output.
Public Member Functions inherited from JSBSim::FGSensorOrientation
	FGSensorOrientation (Element *element)

Additional Inherited Members
Public Types inherited from JSBSim::FGJSBBase
enum	{ eL = 1 , eM , eN }
	Moments L, M, N. More...
enum	{ eP = 1 , eQ , eR }
	Rates P, Q, R. More...
enum	{ eU = 1 , eV , eW }
	Velocities U, V, W. More...
enum	{ eX = 1 , eY , eZ }
	Positions X, Y, Z. More...
enum	{ ePhi = 1 , eTht , ePsi }
	Euler angles Phi, Theta, Psi. More...
enum	{ eDrag = 1 , eSide , eLift }
	Stability axis forces, Drag, Side force, Lift. More...
enum	{ eRoll = 1 , ePitch , eYaw }
	Local frame orientation Roll, Pitch, Yaw. More...
enum	{ eNorth = 1 , eEast , eDown }
	Local frame position North, East, Down. More...
enum	{ eLat = 1 , eLong , eRad }
	Locations Radius, Latitude, Longitude. More...
enum	{   inNone = 0 , inDegrees , inRadians , inMeters ,   inFeet }
	Conversion specifiers. More...
static const std::string &	GetVersion (void)
	Returns the version number of JSBSim.
static constexpr double	KelvinToFahrenheit (double kelvin)
	Converts from degrees Kelvin to degrees Fahrenheit.
static constexpr double	CelsiusToRankine (double celsius)
	Converts from degrees Celsius to degrees Rankine.
static constexpr double	RankineToCelsius (double rankine)
	Converts from degrees Rankine to degrees Celsius.
static constexpr double	KelvinToRankine (double kelvin)
	Converts from degrees Kelvin to degrees Rankine.
static constexpr double	RankineToKelvin (double rankine)
	Converts from degrees Rankine to degrees Kelvin.
static constexpr double	FahrenheitToCelsius (double fahrenheit)
	Converts from degrees Fahrenheit to degrees Celsius.
static constexpr double	CelsiusToFahrenheit (double celsius)
	Converts from degrees Celsius to degrees Fahrenheit.
static constexpr double	CelsiusToKelvin (double celsius)
	Converts from degrees Celsius to degrees Kelvin.
static constexpr double	KelvinToCelsius (double kelvin)
	Converts from degrees Kelvin to degrees Celsius.
static constexpr double	FeetToMeters (double measure)
	Converts from feet to meters.
static double	PitotTotalPressure (double mach, double p)
	Compute the total pressure in front of the Pitot tube.
static double	MachFromImpactPressure (double qc, double p)
	Compute the Mach number from the differential pressure (qc) and the static pressure.
static double	VcalibratedFromMach (double mach, double p)
	Calculate the calibrated airspeed from the Mach number.
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).
static bool	EqualToRoundoff (double a, double b)
	Finite precision comparison.
static bool	EqualToRoundoff (float a, float b)
	Finite precision comparison.
static bool	EqualToRoundoff (float a, double b)
	Finite precision comparison.
static bool	EqualToRoundoff (double a, float b)
	Finite precision comparison.
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 Public Attributes inherited from JSBSim::FGJSBBase
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
static short	debug_lvl = 1
Protected Types inherited from JSBSim::FGSensor
enum	eNoiseType { ePercent =0 , eAbsolute }
enum	eDistributionType { eUniform =0 , eGaussian }
Protected Member Functions inherited from JSBSim::FGSensor
void	ProcessSensorSignal (void)
void	Noise (void)
void	Bias (void)
void	Drift (void)
void	Quantize (void)
void	Lag (void)
void	Gain (void)
void	bind (Element *el) override
Protected Member Functions inherited from JSBSim::FGFCSComponent
void	Delay (void)
void	Clip (void)
void	CheckInputNodes (size_t MinNodes, size_t MaxNodes, Element *el)
Protected Member Functions inherited from JSBSim::FGSensorOrientation
void	CalculateTransformMatrix (void)
static std::string	CreateIndexedPropertyName (const std::string &Property, int index)
Protected Attributes inherited from JSBSim::FGSensor
enum JSBSim::FGSensor::eNoiseType	NoiseType
enum JSBSim::FGSensor::eDistributionType	DistributionType
double	min
double	max
double	span
double	bias
double	gain
double	drift_rate
double	drift
double	noise_variance
double	lag
double	granularity
double	ca
double	cb
	lag filter coefficient "a"
double	PreviousOutput
	lag filter coefficient "b"
double	PreviousInput
int	noise_type
int	bits
int	quantized
int	divisions
bool	fail_low
bool	fail_high
bool	fail_stuck
std::string	quant_property
Protected Attributes inherited from JSBSim::FGFCSComponent
FGFCS *	fcs
FGPropertyManager *	PropertyManager
std::vector< FGPropertyNode_ptr >	OutputNodes
FGParameter_ptr	ClipMin
FGParameter_ptr	ClipMax
std::vector< FGPropertyValue_ptr >	InitNodes
std::vector< FGPropertyValue_ptr >	InputNodes
std::vector< double >	output_array
std::string	Type
std::string	Name
double	Input
double	Output
double	delay_time
unsigned int	delay
int	index
double	dt
bool	clip
bool	cyclic_clip
Protected Attributes inherited from JSBSim::FGSensorOrientation
FGColumnVector3	vOrient
FGMatrix33	mT
int	axis
static Message	localMsg
static std::queue< Message >	Messages
static unsigned int	messageId = 0
static constexpr double	radtodeg = 180. / 3.14159265358979323846
static constexpr double	degtorad = 3.14159265358979323846 / 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/(fttom*fttom*fttom)
static constexpr double	in3tom3 = inchtoft*inchtoft*inchtoft/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.
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

Detailed Description

Encapsulates a Accelerometer component for the flight control system.

Syntax:

<accelerometer name="name">
  <location unit="{IN | M}">
    <x> number </x>
    <y> number </y>
    <z> number </z>
  </location>
  <orientation unit="{RAD | DEG}">
    <pitch> {number} </pitch>
    <roll> {number} </roll>
    <yaw> {number} </yaw>
  </orientation>
  <axis> {X | Y | Z} </axis>
  <lag> number </lag>
  <noise variation="PERCENT|ABSOLUTE"> number </noise>
  <quantization name="name">
    <bits> number </bits>
    <min> number </min>
    <max> number </max>
  </quantization>
  <drift_rate> number </drift_rate>
  <gain> number </gain>
  <bias> number </bias>
  <output> { output_property } </output>
</accelerometer>

Example:

<accelerometer name="aero/accelerometer/right_tip_wing">
  <location unit="IN">
    <x> 43.2 </x>
    <y> 214. </y>
    <z> 59.4 </z>
  </location>
  <axis> Z </axis>
  <lag> 0.5 </lag>
  <noise variation="PERCENT"> 2 </noise>
  <quantization name="aero/accelerometer/quantized/right_tip_wing">
    <bits> 12 </bits>
    <min> 0 </min>
    <max> 400 </max>
  </quantization>
  <bias> 0.5 </bias>
  <output> aero/accelerometer/right_tip_wing </output>
</accelerometer>

The only required element in the accelerometer definition is the input element. In that case, no degradation would be modeled, and the output would simply be the input.

For noise, if the type is PERCENT, then the value supplied is understood to be a percentage variance. That is, if the number given is 0.05, the variance is understood to be +/-0.05 percent maximum variance. So, the actual value for the accelerometer 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 time.

Author

Jon S. Berndt

Version

Revision

1.9

Definition at line 129 of file FGAccelerometer.h.

Constructor & Destructor Documentation

FGAccelerometer()

JSBSim::FGAccelerometer::FGAccelerometer	(	FGFCS *	fcs,
		Element *	element )

Definition at line 53 of file FGAccelerometer.cpp.

~FGAccelerometer()

JSBSim::FGAccelerometer::~FGAccelerometer

(

)

Definition at line 77 of file FGAccelerometer.cpp.

Member Function Documentation

Run()

bool JSBSim::FGAccelerometer::Run ( void )

overridevirtual

Reimplemented from JSBSim::FGFCSComponent.

Definition at line 84 of file FGAccelerometer.cpp.

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

• FGAccelerometer.h
• FGAccelerometer.cpp